| South Bend Lathe Unit Codes
(Jan 30, 2001) |
Shop tip of the day!
(Jun 18, 2003) |
| Metal castings (Apr 17,
2001) |
Broken tap in Aluminum
(Jun 24, 2003) |
| How should I insure my hobby
machine shop? (May 26, 2001) |
Another Shop tip of the day!
(Jun 28, 2003) |
| Shop tips (Jul 12, 2001) |
Terms - Live Center (Jun
30, 2003) |
| Machine shop 101 (Jul 15,
2001) |
Shop tip of the day!
(Jul 8, 2003) |
| Shop tip Question? (Aug
9, 2001) |
Harbor Freight tool grinder
(Aug 5, 2003) |
| Scratching cast iron-Turcite
(Aug 15, 2001) |
Building a Chuck Thread Cleaner
(Aug 24, 2003) |
| Low-tech mandrels (Oct
12, 2001) |
Who was wishing for "Blue
Chips"? (Sep 5, 2003) |
| Knee boot toe saver (Dec
8, 2001) |
Cutting aluminum (bandsaw)
(Oct 5, 2003) |
| Bi-metal blades? (Dec 9,
2001) |
Question on dies (Oct 6,
2003) |
| Blackening Procedure
(Jan 12, 2002) |
Cutting piston retaining grooves
(Oct 8, 2003) |
| Machine Tool Rebuilding
(Jan 19, 2002) |
Marking items we make?
(Dec 4, 2003) |
|
Coil springs (Feb 2, 2002) |
Paraffin as a Penetrating oil
(Dec 30, 2003) |
| Stuck screws-Save the Slots!!
(Feb 8, 2002) |
Has kerosene been banned?
(Dec 31, 2003) |
| Do NOT use Brillo pads on ways!
(Feb 16, 2002) |
2-56 set screws needed
(Feb 18, 2004) |
| Safety advice (Feb 28,
2002) |
Fine vs. coarse thread
(Jan 6, 2005) |
| Brass wool vs synthetic steel
wool (Mar 18, 2002) |
Using arbors (Mar 21, 2004) |
| Slightly OT - Drill Chuck
(Apr 2, 2002) |
Broken tap (Mar 22, 2004) |
| Need some hand tools
(Apr 20, 2002) |
Starrett Center Gage (Apr 20, 2004) |
| Shop tip (Aug 31, 2002) |
Dynamic balancing on a lathe? (Apr 25, 2004) |
|
How to Tip with live center
to clamp disk against headstock (Sep 6, 2002) |
Geometric die head (May
2, 2004) |
|
Broken tap removal (EDM) (Oct 25, 2002) |
Practice projects? (May
7, 2004) |
| Duplicator (Dec 16,
2002) |
Small precision lathe
(Jun 28, 2004) |
| Grounding work in the lathe
(Dec 17, 2002) |
Brass bronze stock (Jun
30, 2004) |
| Back pinion tooth repair
(Dec 30, 2002) |
Repairing a cracked casting
(Aug 5, 2004) |
| Mill/Drill lubrication system
(Jan 17, 2003) |
WD-40, something to try, it
works for me! (Sep 13, 2004) |
| Loctite and Bearings
(Jan 22, 2003) |
Swarth (Oct 21, 2004) |
| Vacuum tip for chips - CAUTION
(Jan 28, 2003) |
Cast iron surface
prep (Nov 3, 2004) |
| Drill press chuck (Mar
11, 2003) |
Tolerances
(Nov 8, 2004) |
| Simple fixturing solution
(Mar 11, 2003) |
Why 'engine' lathe?
(Nov 23, 2004) |
| Metal Lathe Castings and Parts
(Apr 28, 2003) |
Math (Jan
13, 2005) |
| Winding coils (Apr 30,
2003) |
Calipers cost?
(Jan 14, 2005) |
| Lighting a lathe (Apr
30, 2003) |
Machining
Definitions (British?) (Jan 19, 2005) |
| Smaller/hobbyist mill
recommendations? (May 13, 2003) |
DTI Mounting
(Feb 2, 2005) |
| Press Fits (Jun 13,
2003) |
|
| |
| South Bend Lathe Unit Codes |
| Have any
of you noticed the unit codes on the sub-assemblies of your lathes?
I have been looking at them for a few years and have come to some
conclusions. Let's look at the apron on a model A lathe as an
example. Your lathe may have a code like this: A 101 NK the first
letter identifies the sub-assembly. (A - apron, C - compound, H -
headstock, etc.) The number identifies the generation or design.
(100 - first generation, 101 - second gen. etc.) I have seen
headstocks as high as 117! The letters in the suffix identifies what
size lathe the sub- assemblies fit. (N - nine inch, K - 10K, R -
heavy ten, L - heavy ten (large spindle), T - thirteen inch, F - 14
1/2", H - sixteen inch). Early nine inch lathes would have an apron
code like: A 100 N Because there wasn't a 10K lathe yet. Of course,
sub-assemblies unique to the nine inch machines wouldn't have a "NK"
suffix code. This information can come in useful when scrounging for
parts and accessories. For example, a steady rest may have a unit
code stamped adjacent to the inverted "vee" way like: SR 100 N which
decodes into: SR - steady rest, 100 - first generation, N - nine
inch lathe. Not all accessories were stamped with unit codes (early
stuff wasn't). But you can still identify stuff sometimes. Most of
the South Bend Lathe castings have "SMF" cast in them somewhere
(Southbend Metal Foundry?). Sometimes you can see a part number cast
into the part. These usually start with PT and will end with the
same suffix codes mentioned before. Now a note of interest; some
attachments and parts of sub-assemblies will fit more than on size
lathe. The apron example is straight forward but let's say you have
the upper portion of a steady rest and the part number is something
like: PT #### NR. This means that it fits lathes nine inch through
heavy ten (i.e. N, K, and R lathes). I have seen exceptions to these
rules. The main one I can think of is the saddle. Most saddles will
have codes like: S 102 NK but I have seen some that are S 400 NK and
these seem to be a little heavier in the webbing of the casting at
the back that forms the rear "vee" way. Also, as a side note, the
quick-change gearbox on early nine inch machines had only one oiler
on top while later machines have two. I don't know when this change
occurred or if this is when the 10K machine came out. But I think
this change was made before the 10K came out. Let me know what you
have observed on your machines. Webb (112) |
| Metal castings |
| When I was in
high school some 50 years ago and in metal shop there were quit a
few co. selling casting kit of different tools and project that could
be made on a lathe or mill. Does any one know if these co. still
exist ? Bill (529) |
| With some cross-slide with T-slots, milling attachment, etc, you
have to machine the raw castings yourself, or I recall you can pay
someone to do it for you. I'm interested in the cross-slide casting,
but w/o a mill I'd have to pay someone to machine it for me. Paul R. (530) |
| Get the Dave Gingery
foundry and lathe books from Lindsay's. You may decide to make your
own. Rick (535) |
| Sure. Other people have been talking
about tools designed more-or-less specifically for the South Bend
9", but there are many companies selling castings for all sorts of
tools, steam and IC engines, etc. Of course, I don't have any names
for you :-( But, you can find such things by searching on the web,
usually for things like "model engineering." Magazines like
"American Machinist" and "The Home Shop Machinist" will have more
pointers. Oh, I'm another new member (been reading the group for a
while though). I've got a 9" model A from 1947. Got it from my Dad,
who had it from his Dad. Preston
(539) |
| Preston, I
think its wonderful that you have a SB that's been in the family for
many generations. You'll have to share a picture of your lathe with
the group. That's right about items for 9" SB lathes in the
magazines. I started with HSM and MW about a year ago and have the
sets of books from those publications. I have yet to get the Shop
Wisdom or Bedside Readers, but the books and magazines I do have are
a terrific resource for projects and parts. Paul R. (540) |
| Check out the
Bookmarks section of this group. Pat's Links have a section called
Foundry Links . Lots of stuff on Castings. Pat's Metalwork Links A
Collection Of Links To Bulletin Boards, Home Shops, How-tos,
Projects, And More.
http://www.angelfire.com/ks/mcguirk/metalworklinks.html (541) |
| I'll need to get a camera
first! It looks about like everyone else's, but still in (somewhat
battered) SB grey. Has a taper attachment, a collet rack with a
reasonable assortment, 3 and 4-jaw chucks, a selection of tools,
etc. I've been filling in some of the holes (new cutoff tool and
holder, a few end mills). The costs are shocking! I think the
"assorted" tools that came along with the lathe are worth about
twice as much as the lathe itself. Mostly I make aluminum and delrin
bit for model airplanes. Recently bought a finished cross-slide from
Metal Lathe Accessories and have started working on the transfer
block. First thing I've machined from a casting. Lots of fun,
watching the finished form appear. Preston
(543) |
| Preston, You'll
have to give us your impressions on the cross slide from Metal Lathe
Accessories, and the quality of the machining. I've been thinking
about getting one, but $200+ is a major step to vertical mill, and
then I'd have less of a need for the cross slide (except for boring
operations or rear tool post). It's still on my list, however. It
sounds like you do have a lot of accessories. Very cool that you
have a taper attachment and collets. If you have been getting some
end-mills, I presume you have a milling attachment? So far, for
milling with the 9" SB, I've been clamping things to the tool post
or the cross-slide to bootstrap my new QC tool post mount. Works
pretty well if things are tight and you take light cuts.
Paul R. (544) |
| Preston, I am a Modlel R/Cer myself. I bought my lathe for the same type of work.
Jim (545) |
| Metal Lathe
Accessories, and the quality of the machining. I've been thinking
about getting one, but $200+ is a major step to vertical mill, Yeah,
I'd love a milling machine (CNC too!), but am really short of room.
The cross slide looks good. It has 3 T-slots and is tapped for 6
studs (5/16-18). There's a hole in place for mounting the compound
slide and holes drilled and tapped for the "compound retaining
screws" (or whatever they are called). It didn't fit, out of the
box, and I had to reduce the thickness of the supplied gib by about
5 thousandths. Painfully. I do. Made by Palmgren. Clamps onto the
tool post. Not especially rigid, but ok for milling aluminum. Part
of my incentive for the cross-slide, etc., is to get a more rigid
setup. I also like the additional flexibility. I guess I'll be
working a while to build all these accessories, but I think they'll
be useful exercises (since I'm just a beginner). Preston
(546) |
| How should I
insure my hobby machine shop? |
| How do you
insure your hobby machine shop? My CPA is telling me I should have
some insurance. My insurance company says I wouldn't be covered by
my homeowners policy. What should I do?
(714) |
| Unless you use the
shop for business (e.g. selling what you produce, or selling your
services), it should be covered as "personal property" or "contents"
under the homeowners policy, even if its a separate building on the
property. If it is used for business, then tell your insurance to
add a rider to the policy to cover the shop, or issue a separate
policy. Be sure you have "replacement cost" coverage on personal
property as well as the building (some insurance companies don't
offer both, so shop around). Replacement cost coverage will add a
few dollars to the premium, but if you have a covered loss that
destroys an old Bridgeport mill, it will buy you a brand NEW one
(~$12,000...ouch!). Without the replacement cost rider you might
collect ~$2,000. Have you priced a NEW South Bend lathe lately? Add
up what it would cost to replace (with new) all the machines, tools,
materials, etc, as well as the contents of the house (appliances,
clothing, furniture, etc); Your policy "contents" limit should be at
least that much. If your insurance agent can't explain this to you,
find another agent. Also take the time to read and understand the
insurance policy, its coverage limits and its exclusions (VERY
IMPORTANT!). There's more there than just the 165 lines of the
"standard New York fire policy". Ken
(716) |
| Shop tips |
| SPEED CENTERING For
those of you new to the trade, there is a very easy way to
rough-center a round piece in a 4-jaw chuck. I put a bar the same dia
as the one to be machined in my tail stock. It gets you within a few
thousandths from center. Just start by accumulating stub-ends from
your scrap-box. Turn down the ends to match the max opening of your
tailstock chuck, (usually a 1/2").A complete set of 1/8" increm. up
to 2" comes in real handy. CHANGING CHUCKS A broom-handle shoved
into the bore and tightened in the chuck is the safest way to change
chucks IMHO. Or better yet take a piece of 1" CRS and skin down one
end of it to fit your tail stock chuck. Put the other end inside the
main chuck and snug it just enough to change out. With some
practice, you can get a perfect alignment to start your threads.
Ron
(1072) |
| Ron, Thanks a lot
for the tips! I've been "fiddling" with cutting coarse threads on my
9" SBL and have had mixed results. I'd sure like to see a "step by
step" list of what the "pros" do. I seem to have trouble getting the
cutter to follow the original cut exactly, even when using the
thread chasing dial. The only way I've gotten fairly consistent
coarse threads is to engage the half nuts, make the cut, turn the
motor off, put in reverse going back to starting point, and re-cut a
little deeper. All the while never disengaging the half nuts. Surely
this isn't the way the pros do it. Any tips on the subject would be
very helpful. Jim (1073) |
| I also have a
problem remembering the "rules" of what lines to use on the thread
dial. So my answer is simple.. I ALWAYS use the same line on the
thread dial to engage the half nuts. This way, I don't have to try
to figure out which ones are "safe" to use. Now before anybody says,
but that costs time, I will state that I am not in a production
setting; but a HOBBY setting where I am trying to relax and spend
some time. So if it cost me an extra 10 seconds per half nut
engagement, SO WHAT? (1075) |
| Not familiar with
your particular model, but you should not have to leave the
half-nuts engaged (on any lathe made in the last 100 years or so).
Some lathes you have to stay on even or odd numbers, or 1/2 numbers.
Some you can engage the half-nuts...gently...on any mark. Some it
depends if you're cutting even or odd TPI. When starting to chase a
thread, go a few thou deep, and take a couple passes without going
any deeper, trying different numbers on the threading dial. It will
be readily apparent which numbers are "right". You are backing out
at the end of each cut with the cross slide, then returning it to
zero for the next cut, and doing infeed with the compound set at 29
degrees...right? It does take a little practice. Your "fiddling" is
the way to learn. Have fun chasing them threads! Jeff (1077) |
| Machine shop
101 |
| I can cover the
subject of cutting left-hand threads or cutting INTERNAL threads
first. Which do you prefer? In the coming months I can cover
whatever topics you wish. Just let me know. regards, Ron BTW, went
to a garage sale yesterday. I found a Mechanix Illustrated circa
May, 1945 in excellent condition. I paid 75 cents for it! This book
had a full-size ad for SBL on the back cover. The rest of the issue
was full of ads that heavily referred to WWII. Ina thinks it's worth
a bit more then what I paid for it. So do I but for different
reasons.
(1091) |
| I would be
interested in internal threads before left hand threads. Thanks for
the info. I'm tucking your tutorials away for a short time until I
get to the point where I can use this information. Steve
(1092) |
| Ron, I am
enjoying the tutorial very much. Personally I would prefer an inside
thread tutorial first. As I posted earlier, I got into lathes and
machining because of my interest in fountain pens. Both the barrel
and the cap need to be threaded. I would also very much like to see
your technique for multi lead threads. Traditional pen manufacture
used triple lead threads so that one twist of the cap would tighten
it and you got several threads to engage for strength. On my little
Sherline hobby lathe I disengaged the threading gears and rotated
the chuck by 120 degrees for each lead. This always seemed a risky
and painful process. On my SB I lined up the compound slide parallel
with the work and advanced the tool 1/3 of the pitch for the second
and third leads. Glen (1095) |
| Ron, I'd prefer
the coverage of left-hand threads first, as I have a direct
application for them, but would be happy to see either subject.
Great job on the previous tutorials. Jim
(1098) |
| Although not new to machining, I am enjoying the tutorials also.
That little thread polishing device is an idea I had never
considered. Regarding multiple start threads, American Machinist's
Handbook (8th Edition, 1945) shows a special faceplate for cutting
multiple threads. It is made in two pieces-one screws onto the
spindle and the other which drives the workpiece is made to rotate
on the first, concentric to the spindle. Indexing is accomplished by
a taper pin and a circle of 12 holes. Theoretically, this device
could be used for up to a 12 start thread, but more likely for 2, 3
and 4 starts. I have text only E-mail, but if anyone has this book
and can scan it, the drawing is on page 84. The drawing likely
appears in other editions of the book also. Tom (1100) |
| Shop tip
Question? |
| Drill/mill/reamer to big? Let it rot down in Navel Jelly for 3
hours. Check it with a micrometer every hour till you know what the
rate of etch is. Also works great with sharpening files. That's an
interesting shop tip. Question: Can you do the same thing with
battery acid? We used to use the acid from old batteries to etch
patterns in knife blades. Just a thought as I don't have any Naval
Jelly around the place, but Bubba's Battery Shop is just down the
road. I have a lot of old files that I wish were sharper.
Bubba K. (1280) |
| Battery or Muriatic acid is perfect for this application. Just keep it away
from anything alum. Ron (1281) |
| Scratching cast
iron-Turcite |
| Some may recall my
earlier post (back in May) regarding an SB13 scraping project. As an
update, I would like to say that the machine is now up and running
and doing very well ...... for a critter old enough to be
eligible for SS. It did not, however, reach completion in the
fashion I had earlier anticipated. To make a long story short; as I
was reaching the final stages of way scraping and saddle fitting, a
pristine SB13 bed appeared on ebay. Since the seller was here in the
west, I bid on it ...... for the grand sum of $51 ...... and was
successful. It cost more in gasoline to retrieve it than it cost to
purchase but it was worth it. The bed was as advertised and worth
every nickel of the cost. So, the ultimate scraping project may not
have ended in total completion ........ as a scraping project ......
but much was learned along the way and a useful tool has been
resurrected from, what was, mostly useless cast iron. I just found a
nice, more recent vintage, compound slide with the newer and larger
micro dials and a face plate, which will lend greater ease of use to
the machine. As matters now stand, this machine has it's birth in
1934 ...... with various appendages replaced along the way. The
headstock and gearing is all original. As is the tail stock, saddle
and apron. The bed is early 80's with turcite build-up in the
saddle. ...... maybe a bit like Johnny Cash's old tune about the
auto worker who set out to scrounge parts for a Cadillac. .......
for those old enough to remember the tune. BTW, the "Turcite"
buildup is really a slick way to compensate for wear in sliding
parts. It performs well, cuts "stick-slip" and has a lower
co-efficient of friction. It is easy to do (relatively), easy to
replace, if need be, and done properly, can bring an old machine
back to original standards. In this machine, the turcite was
installed to compensate for wear in both the original ways as well
as the saddle itself. Since the bed has now been replaced with one
having factory dimension ways, the saddle is now riding .020 high.
Being fundamentally lazy and unable to see any problem with a saddle
riding .020 higher than original, it will remain at the present
level ........ unless something presents a reason to conclude
otherwise. I did, however, shim (down) both the apron and the rear
gib by an equivalent amount in order to accommodate the longitudinal
gear rack, lead screw and the rear gib surface. In the meantime, it
has about 100 years of wear ahead of it, before the saddle returns
to original height and the shims can be removed. The tail stock
baseplate was built up with a wear resistant epoxy. I would have
used Turcite again but didn't have any in thin sections.
Surprisingly, it only required .010 on the flat and .005 on the
inverted V. But the inverted V was flared several thousandths, at
the forward end. The base plate was shimmed level and to proper
height for spindle center. Narrow brass shims were super glued in
place for the epoxy phase. A strip of wax paper serve's nicely to
prevent adhesion to the ways. Weight the base plate and check for
level and square to the center line axis. The wear resistance epoxy
is very tough and resistant to wear. A cold chisel is required to
remove it ......... or better, heat to 300 or 400 degrees and
scrape it off. My only long term concern is that it may prove
deleterious to the cast iron ways. But that's an easy matter to keep
an eye on. If there's any sign of scratching or wear, the epoxy will
be replaced with Turcite. I put a Phase II CXA, wedge type tool post
on it. The original 3 PH motor was replaced with 1 1/4 HP DC motor
and speed control. The leather belt was replaced with a flat belt
from a local distributor. I have taken .030 (.060 total) cuts in
steel without belt problems. I'm still in the test and sniff (for
problems) phase but so far, the accuracy is within my limits of
testing and it is performing very well. ....... but it has been
a time consuming project. Tip: With a DC drive and speed control,
there is no reasonable way to determine spindle RPM, without a tach.
I solved the problem with a length of allthread and a stop watch.
Wrap tape around the nut ...... or otherwise build it up ......
so it fits securely inside the spindle. Time the advance of the nut
as it's being driven down the length of allthread by the spindle.
Measure the distance the nut travels and multiply by the pitch of
the threads. If timed for one minute, that will equal the RPM. A
fine pitch thread, like 1/4 - 20 will work better for higher RPMs.
And of course, some care should be taken since the rod must be hand
held. I did the measurement for each pulley step and each 10 unit
advance on the speed control. A handy table of spindle speeds, now
adorns the face of the speed control.
(1311) |
| Very
interesting, I have just purchased a partial 13" SB lathe for parts
for my 13" 1939 model. Wanted the spindle and motor, paid $80. I
also got the bed, whole stand, headstock, saddle base, apron and all
gears (some handles missing). someday I might be interested in
parting in this lathe, vs continuing to part it out. Are there any
good sources of information out there about scraping the ways etc. I
have done some bearing scraping in my younger days where we would
scrape in large shafts for very large presses at Danley Machine in
Chicago, we'd use bluing on the shaft, drop it in tighten it rotate
it and then scrape the high spots. Appreciate any sources on this in
I guess truing the ways. Also, does the headstock (now removed) have
to be somehow realigned when it is reattached to the bed. I noted a
alignment pin in it that fits into the bed. big tom (1319) |
| There's an book
called "Machine Tool Reconditioning" by Connelly. It's pretty
expensive. There's been mention of a possible group buy to get a
reduced price--look in rec.crafts.metalworking. Michael Morgan has
produced a book and a video on scraping. (1324) |
| I looked at
the South Bend Page and they use turcite in their new products. I
was wondering what exactly it is and where its available from? How
is it attached to the ways, Glue Soildering? Tom (1326) |
| I just typed
Turcite into Yahoo's search engine and I got back links to Boedeker
plastic's data sheet on Turcite. It is related to Delrin which is a
plastic material I've used before. Very easy to machine, takes a
high polish and is extremely strong and "slippery".
http://www.boedeker.com/turcax_p.htm
Glen (1327) |
| Yes, Turcite is
Delrin plastic which has been filled with Teflon. In sheets it's
called Turcite B, as I recall. Slydway is also a reg. trademark. In
other shapes it has other names. I bought the material I used from
Zatcoff Seals and Packings. In terms of volume, the stuff is relatively expensive but since it
can be cut to your specs it becomes quite reasonable in cost.
Especially since most applications require only narrow strips. Cost
increases directly by thickness. A special epoxy is used to cement
the Turcite into place. ....... thorough degreasing of the
bonding surface is a must. Do not use hydrocarbon based degreasers.
The epoxy is the probably the most expensive part of the system. A
half pint can ........ minimum quantity ....... was $80 as I
recall. ...... and will no doubt exceed its shelf life before you
use it all. Very little epoxy is used in the process. ..........
BTW, the back side of the Turcite has been chemically etched to
allow adhesion to the epoxy. Keep it clean. At the present time, I
am revisiting the cross table slide and improving the fit. Both to
remove some remaining pinch and also to get rid of some chatter on
harder steels, that I believe is related to the slide. At some
point, I may very well install Turcite on that slide as well. Earl
(1328) |
| Low-tech
mandrels |
| Chris is using
these very fine mandrels for drawing thin brass parts for French
Horns. So I ask a dumb question here. How critical is this long
taper from one inch to the next? Since you will be hardening these
anyway, won't there be minute changes in your work-piece? I imagine
you will want to go back and finish the mandrels afterwards. Have
you already tried the low-tech approach of long taper-jigging and
then finishing with gages and bluing? It is time-consuming but
accurate. How many mandrels do you need? I believe the Carpenter
Steel Co. is still in business. If you can find their book on tool
steel, it may be a big help towards selecting a good A/H. Ron
(1821) |
| Ron, I believe I
would be rather happy if I could hold a tolerance of +/- .001 on the
diameter of the finished mandrels for now. One thing that is
critical is that they always taper in the same direction, or pulling
the mandrel out of the drawn tube gets difficult. I am not hardening
them - at the moment I'm experimenting with the musical qualities of
various tapers, so I don't need to use the mandrels that many times
- and I have no way to heat something that long evenly. Someday I
might build a long pipe burner for annealing brass tubing, and might
try that with air hardening steel. As the 'master' for these tapers
is simply a spreadsheet, there isn't really anything to compare them
against with bluing, and they don't need to be that accurate anyway.
Just for comparison, my previous method of making these was to stick
and inch of rod out of the chuck, machine a stairstep or two (in
several passes) approximating the taper, then rechuck with another
inch sticking out. Every once in a while I'd grab a file and smooth
out the stairsteps... It worked in the 1830's and still works today,
but tools made accurately in this fashion are expensive, whereas I'd
like to find a way to make them cheaply enough to permit design
experimentation. Chris
(1822) |
| Christopher writes: ---
One thing that is critical is that they always taper in the same
direction, or pulling the mandrel out of the drawn tube gets
difficult. Now we're getting to it. Some of your thoughts have been
on target, some not. What you want is a direct read out DRO for
longitudinal feed, a direct read out for cross feed, an electronic
drive motor (stepper motor, servo motor, or ?) for cross feed, and a
program (CNC ?) to drive the cross feed relative to the known
position of the longitudinal feed. Set up the cut to run from the
larger diameter to the smaller diameter. This means if you have the
large diameter next to the headstock make your longitudinal traverse
from left to right (obviously right to left if you're willing to
place the large diameter at the tailstock end). This will insure
that the cross feed will always take up any slack in the feed screw.
You don't need ball screws, you don't need zero back lash, you don't
need special thrust bearings. As long as the cross feed during the
cut is inwards the slack will be removed and the position is
controlled by the direct read out, the stepper motor, and the CNC
program. Does this make sense to you? Anthony
(1830) |
| And please remember
to turn towards the headstock rather than towards the tailstock
whenever possible. The headstock (at least on older SBs) has a
thrust bearing only for a force towards the headstock. Additionally,
turning towards the tailstock puts additional force on the tailstock
center. Dead centers are generally more accurate, but prone to
friction burning if not monitored during machining. Turning towards
the tailstock just adds to the problem. Paul R.
(1831) |
| Anthony, for a
larger diameter workpiece this idea would have merit. It would load
the spindle in a thrust direction for which it is not really
designed, but that shouldn't be a problem in a non-production
situation. Because my workpieces go down to 1/2" I'd really rather
cut towards the tailstock so that torque is being transmitted
through the 1/2" uncut stock rather than through the stock I've cut
down. Linear encoders are nice in that they give you a reading
independent of screw backlash, however one does *not* want to try to
close a servo loop across one using a screw wish has lash - we have
such a setup in a precision slide at work which got contaminated
with aluminum oxide and developed a tiny bit (around .001") of
backlash. In certain circumstances, the servo loop will go into
oscillation across the lash, so I have to shut down that axis when I
do high acceleration moves with other axis that shake the whole
machine (the base is unfortunately welded steel tubing - it should
have been a welded box filled with sand or polymer concrete) Anyway,
feed always in the opposition to the cutting force is a good
principle - one on which almost every manual machine tool depends.
Chris
(1832) |
| Er, that should be
because the workpieces go down to 1/4" diameter and stay small for
quite some distance. Also, I will need to rechuck since the piece is
longer than the lathe, and I'd rather do that on uncut 1/2" diameter
stock. Chris
(1833) |
| Knee boot toe
saver |
| This may not be
original but it sure works. Dropped a tiny screw on the shop floor.
Took one of the wife's old nylon stockings I save for paint
strainers. I let the shop vac suck the whole thing in toe first and
then wrapped the remaining 4" around the outside of the hose. Sucked
up a big area on the floor and then dumped the sock out onto a white
paper. PRESTO the screw appeared.
(2356) |
| This is an
excellent idea, but requires the discipline of vacuuming the floor
before you start work. I can tell you from hard experience it don't
work worth a hoot when you've just finished milling 30 pounds of
aluminum swarf onto the floor and are trying to fit a part. :-) More
seriously, this works very well - highly recommend it, especially as
you get older and your eyes and grip aren't what they used to
be.. (2358) |
| Bi-metal
blades? |
| Does anyone know
the secret in breaking in a bi-metal hacksaw blade. I have a 64.5"
power hacksaw and sometimes one of these blades last forever and the
next time in a month or less it's toast. Someone once said you have
to first break them in, in a certain way ? Maybe cut a couple
inches of brass or soft pig iron first?
(2373) |
| The _Machinery's
Handbook_ states: "A new bandsaw blade must be broken in gradually
before it is allowed to operate at its full recommended feed rate.
Break-in relieves the blade of residual stresses caused by the
manufacturing process so that the blade retains its cutting ability
longer. Break-in requires starting the cut at the material cutting
speed with a low feed rate and then gradually increasing the feed
rate over time until enough material has been cut. A blade should be
broken in with the material to be cut." Then the book shows 2
graphs: for "% of starting feed rate" as a function of band speed,
and "total break-in area required" [the cross-sectional area of
material sliced ???] as a function of band speed. The starting feed
rate drops from 100% when bands speed is 40 ft/min down to near zero
when band speed is 360 ft/min. The break-in area increases from 0 to
100 square inches, as band speed goes from 40 to 360 ft/min. I
suppose that the reasoning for breaking in bandsaw blades also
applies to power hacksaws. So, I guess you should just be very light
on the feed pressure of a new blade, gradually increasing as the
blade is used. (2376) |
| Blackening
Procedure |
| Spent some
time making a few parts and tools recently from steel and would like
to blacken them. What is the best procedure for this? I've seen a
product called Tool Black and I'm wondering if I should purchase it.
Also, is it possible to blacken aluminum? Al
(2689) |
| You can get
Birchwood Casey cold blue from your local gun shop. Brownell's Ospho
bluing compound will probably do a better job for you, though.
Depending on what you're bluing/blackening, you might just want to
heat it with a torch until it turns color. This doesn't work, of
course, for hardened or heat treated items. Yes, there is an
aluminum blackening compound. Check with your gun shop. IIRC, that's
where I got mine; however, you may want to look into anodizing the
aluminum. You'll probably get better results that way. Orrin (2690) |
| Like Orrin said
http://www.brownells.com/index.html has gun blueing and Aluminum
blackening that will work for you. Nice people to deal with, IMHO.
BTW, with a little practice, you can do a very nice imitation of
"color case hardening" with Brownell's OXPHO-BLUE.
(2692) |
| In my book "The
Home Machinist's Handbook" [definitely entry-level, Sherline-based
stuff] it says that you can get a nice black finish on steel just by
dipping it in motor oil and baking at 350F for an hour. I've found
vegetable oil and a toaster oven only puts a sickly brown finish on
that comes off with a wire brush and some elbow grease. If you try
motor oil let me know the results, ok? Machinery's Handbook says
iron and steel are "blackened by immersion in a boiling mixture of
sodium hydroxide and mixtures of nitrites and nitrates"--I know
sodium hydroxide is plumber's lye but they don't say what
nitrites/nitrates. I remember the last job I had before this one had
a two-step goop to paint on aluminum that blackened it nicely; I
think it was called "Tool Black" also--perhaps they make it in
multiple versions or perhaps they were supposed to be using it on
steel and were using it on aluminum instead. Also, there is a
product on p.1002 of the Travers catalog
www.travers.com
p/n 81-145-110 also called Tool Black which "imparts a tough, dull
black protective finish to ferrous metal parts"--this is the stuff
you're speaking of I think--the complete set of goops and sealer is
about fifty bucks. There is some stuff at the model-train store
called Hobby Black but I dunno if it works on steel. Depending on
the size of the part, milking a new permanent marker for it's juice
and using an artist's brush or airbrush may have merit. If temper
isn't important, coat it with lard and bury it in coals maybe? My
mom's iron skillets have a beautiful coal-black finish.
(2694) |
| I just went
through the same question - what is best? A matter of opinion to
some extent, but the results I got from a posting on another site
all recommended Oxpho Blue. I purchased and used the Oxpho Blue, and
am totally pleased. If you can sandblast the surface first, the
results are even better (that's what I did). Ken
(2695) |
| With the
aluminum blackening solution, you might try and heat up the aluminum
and apply the solution with steel wool (try and remove the oil on
the steel wool first with alcohol). The steel wool removes the oxide
on the surface of the aluminum. Tom(2710) |
| Machine Tool
Rebuilding |
| I have the
book on machine-tool re-building. I recommend you buy it. It not only
teaches you how to re-condition machinery, but has an insight of how
people thought about doing good work 50 years ago. When you decide
to do this, start by buying a tube of Prussian Blue and hi-spot the
work in question. A straight-edge and leaf-shims are handy to have as
well. Small mill-flat files with glass-hard tips, (or carbide) and
dead-sharp are a must. But, before you begin, you may want to
contact the moglice people and get their literature on re-building.
They are very nice folks to work with, and have a wealth of advice
on the subject. I have talked with a factory-rep concerning my own
lathe. I cases where there is much wear, a combination of scraping
and moglice is necessary. It is a simple matter of filling the low
spots, and scraping the high spots .In the case of bed-ways having
'saddle-wear', the bed must be scrapped. However, a small job like a
cross-slide may be different. I have started making my own set of
scrappers from old files. I have a local source of granite plates
and strips to use as a set of masters to get started. I intend to
re-do the top of my table saw first as a practice. It should be
fun! Ron
(2815) |
| I
have been enjoying the thread on rebuilding and the pictures of
Jonathan's progress. I have never used Moglice but I have read good
things about it. There is another product used to replace or "build
up" a worn or re-machined part but I cannot remember the name of it
right now. Maybe one of you out there can help me. It is called
something like Turcel or Turcite or something like that. I look
forward to more posts. Webb
(2816) |
|
http://www.boedeker.com/turcax_p.htm (2818) |
| Turcite.
Would be really nice to see the progress put up on a web page or is
it? Marty (2819) |
| Webb, et.
al., There are different names for this sort of product. "Turcite-B"
comes in thin flat sheets. I believe it is a Teflon matrix with
metal imbedded into it. One side is smooth and slick, and the other
can bond with an epoxy adhesive. This product is used for both
reconditioning machines AND for new machines. One advantage of it is
that it is easier to replace a small worn Turcite strip than it is
to regrind or scrape a large worn metal casting. Also, Teflon
(Turcite) is more slippery than a metal gib, so the unwanted
"stick-slip" is supposed to be avoided. Jon (2820) |
| Coil springs |
| What is a good
source of info on how to make coil springs with the lathe? Matt
(3058) |
| There is a section
in the Atlas manual that covers making springs. In essence what you
do is to chuck up a rod somewhat smaller than the ID of the desired
spring. Put your wire through the hole to secure it, Put the wire
between something to hold tension (I use a pair of wood popsicle
sticks in my lantern type tool holder) Turn the lathe by hand. For a
tension spring just wrap the coils
close to each other
for a compression spring use the change gears to get the proper
spacing. (Or wind on a threaded rod and unscrew the spring when
done) There will be some spring back so a little experimenting may
be needed. The Atlas manual has change gear set ups for different
spacing. My manual is out in the shop now and it is too cold to go
out to get it. John (3109) |
| For the design of
helical coil springs, _Machinery's Handbook_ has reference
information on different types of steels and calculations for spring
constants. (3110) |
| I forgot to
look it up, but there's a neat article in either one of the seven
"Projects" HSM books or one of the three "Metalworking" MW books (I
forget which). It discusses techniques and setups for winding coils,
and has charts for designing whatever spring force you're looking
for based upon wire gauges. I'll see if I can find which one the
article is in. Paul R. (3111) |
| Try this website;
http://home.earthlink.net/~bazillion/springs.html (3116) |
| Stuck
screws-Save the Slots!! |
Save the Slots!! -
most screws with straight slots, and many Philips, will simply strip
the slot if too much torque is applied to the driver, or if there is
any appreciable taper or round edge to the driver blade - there
almost always is some so there is always the danger of over torquing
the slot. one way to avoid this is to grind a very slight reverse
bevel and sharp corner on the driver, and then put some valve
grinding grit on the driver. best way to save these screws if you
have the tools, is to use an impact tool, either handheld/hammer
type, pneumatic, or electric type. I prefer the hand type for
anything that needs some care in disassembly. you can NOT get all
the things loose with just a hammer and a screwdriver that can be
loosened with this tool. they cost about $10 at auto parts stores
and you will find lots of uses for them if you work on used vehicles
or machinery of any type - they are reversible and usually come with
a few blade type drivers and a square drive adapter for sockets (
great way to tear up your non-impact sockets too). you can easily
adjust the amount of force you apply by changing hammer size and
swing energy, and by just holding the tool differently, lets you
apply a heavy impact blow or many sharp light ones.
(3136) |
| This is one
of the best tools you can put in you box. I was introduced to this
tool over 30 years ago when I started working on cycles and if you
had to tear down a motorcycle engine with out one it can be almost
impossible with all the Philips screws they use. The old British
bikes and some of the newer Japanese models use large inspection
screws, some over an inch and a half across with a straight slot.
The impact driver with a drag link socket is about the only way to
remove them after they have been in place for a few years.
Randy (3140) |
| Thanks for
the info about this tool. I had never heard of it. For large screws,
I have used an old hand brace (the kind that was used for drilling
into telephone poles with an auger bit) with a screwdriver bit
chucked into it. No impact, but better leverage and downward
pressure than a regular screwdriver. I'll check out an auto parts
store next time I can. Jon (3143) |
| Do NOT use
Brillo pads on ways! |
| To keep from
scratching/removing any metal from any of the way surfaces, it is
important NOT to use a material that is harder than the cast iron.
Brillo pads are made of steel wool and an abrasive cleaner. These
materials are harder than rust, so they will scrape it off. However,
they are also harder than the cast iron/"semi-steel" ways, so they
will scratch them too. Obviously you don't want that to happen. I
had good experience using a "copper wool" scouring pad on a 60-year
old Heavy 10 that I just sold. The brand name of the pads was "Chore
Boy," which I got at the local supermarket. They work very well with
a non-abrasive cleaner or solvent. After much work, beneath all the
grunge, the original hand scraping marks eventually were revealed on
the taper attachment ways. Then a spray coat of WD-40 and a layer of
way oil for protection. I think that copper is an ideal material
because it is harder (or tougher) than the rust, yet softer than the
cast iron metal. I don't think that nylon scouring pads would take
off the rust as well as copper. Also, don't use the green type of
kitchen abrasive pads, as they contain an abrasive that will scratch
the metal. Sometimes I think of materials in terms of their
hardness, which is a real and defined mechanical property. In my
head, I rank materials something like this (hardest listed first):
-diamond -silicon carbide (green grinding wheel for carbide toolbits)
-aluminum oxide (regular grinding wheel and sandpaper) -tungsten
carbide (for toolbits) -HSS and tempered carbon tool steel
-stainless steels -common steel alloys (not tempered for hardness)
-cast iron, non-ferrous metals and alloys -the paint on our machines
-hardwoods -softwoods, plastics such as nylon and polyethylene The
general rule is that the "harder" material can scratch, cut, or
gouge the softer material. That is why it is important for us to
keep grinding dust off of our machinery... We don't want the little
abrasive particles to scratch at the lathe ways. This doesn't
necessarily mean that you can't damage a harder material with a
softer material. For example, if we scrub the paint finish of our
lathe with a LOT of force using a soft nylon scouring pad (or even a
jet stream of water), it is possible to break paint chips off off of
the metal. Jon p.s. It helps to get a supply of the
cheap disposable latex gloves that auto mechanics use to keep black
grease off of their hands, though the solvent can eventually eat
through the latex during a cleaning job. (3290) |
| Safety advice |
| The best advice I
ever got regarding safety on machines was from an old timer mechanic
training me on hydraulics. He said - them things have no brains and
no conscience, they'll just as soon cut you in half as not. The only
thing stopping them from doing that is YOU. And this was on machines
with 2500 and 4500 psi hydraulics - a microscopic leak in a high
pressure hose would push the oil right thru your glove and under
your skin if you had a grip on the hose. Do not EVER depend on a
safety device or any presumption of what will happen to keep
yourself safe from the energy in use on a machine. Machines with
even low motor horsepower have very great stored energy in spinning
mass and will cause severe damage to machines and people if not
handled carefully at ALL times. The best way to make them REALLY
unsafe is to add more power. This makes more things break, makes a
lot happen faster than the operator can react and stop it, and makes
sure that any break will do more damage before it limits itself by
running out of energy. Like Pat Morita said in the karate kid movie
- the only way to not be hurt by this is - don't be there!. if you
need more ponies - get the machine built for it. Don't let stupid
tell you a glory story that sorry wishes he never heard of. (3435) |
| Brass wool vs
synthetic steel wool |
| A while
back there was a discussion re removing rust from bed ways with a
solvent and brass wool. Does anyone know if the synthetic steel wool
is harmful or ok to use? (3637) |
| What
synthetic steel wool are you talking about? If you mean the Scothbrite pads, they are made with embedded abrasive. Not a big
deal if you working with a bare bed, as clean up is easy, but likely
not something you would grab if the lathe is built up. There are
scouring pads made just of nylon or some similar plastic that do not
have any abrasive, just a coarse mesh. Stan (3641) |
| Slightly OT -
Drill Chuck |
| I have a
15" Clausing drill press with a 33jt spindle and I'm stumped as to
how to remove the chuck. No one I found lists wedges for a 33jt so I
milled up a set, stuck them on there, squeezed, and promptly pulled
the spindle out of the bearings. Hmmm. There is a threaded collar at
the top of the chuck which seems to serve no purpose? Thought about
heat, but only as a last resort (hardened spindle??). There is no
hole through the center of the chuck, so a puller won't work.
Tentative plan A is to drill a hole through the center of the chuck
(drill bit mounted in the vise??) and fab a puller. The chuck is
semi-expendable (jaws are sprung, replacing it with a keyless) but
it's a good Jacobs and I'd rather repair it than destroy it.
Tentative plan B is to replace the 33jt spindle with a #2 morse
(apparently they were available either way). Anyone familiar with
this procedure? Frank (3789) |
| Actually,
that collar serves a very important purpose, if it is like the drill
press we have. It acts as a removal wedge for the chuck! Rotate the
collar counterclockwise (as when looking up at the chuck) and it
will pop the chuck off the spindle. This is just like the collar on
an "L-" series lathe spindle. Scott Logan (3790) |
| Ah, so the
collar is part of the spindle and not the chuck. I will try this
when I 'obtain a suitable spanner' as they say. Frank
(3803) |
| NO!
WAIT! I was about as clear as Mississippi mud. The collar is part of
the CHUCK, not the spindle. Sorry for the confusion. Scott Logan
(3806) |
| I the Stuck a
picture in photos. The collar will not go all the way up to the
bearing but it will come down tight against the chuck. What I got
from your original reply was to crank it down against the chuck to
pop it off, which would make sense if the collar is on the spindle.
Wedging between the top of the collar and the bearing just pulls the
spindle out. The #2 morse quill is looking better all the time. Frank
(3810) |
| Frank, I am
guessing that your drill chuck is a Jacobs model 33C, which means
that the collar is part of the chuck. This 33C chuck is the same as
a model 33, but the "C" suffix means that it has a collar. When the
chuck is off the spindle, the collar loosely spins and has some
vertical play. It threads onto the spindle, and helps the chuck keep
wedged up onto the spindle so that it won't fall off, the way that a
standard Jacobs taper 33 chuck sometimes can. If you use a spanner
wrench (or even a pin or the end of an old drill bit, with a hammer)
to unscrew the collar down off the spindle, the chuck can be forced
off, either by wedging or by further unscrewing the collar.
Jon (3812) |
| Frank:
what is the number of the chuck? I have the same drill press I think.
What Scott described is correct. you turn the knurled nut to press the
chuck off from the spindle. Jacobs has wedges, but they are sized as
no, 2, no 3, etc... for chuck family size, not by taper. Search for
Jacobs on the net and you can look at their pages for more info. dp
(3817) |
| Frank,
Scott Logan is correct. The collar is screwed down against the base
of the chuck and pushes the chuck off the end of the spindle. The
collar will come off with the chuck. If you don't already know this,
the chuck key can be used as a handle for holding the chuck when
you're screwing the collar down. The end of the chuck key (farthest
away from the beveled gear used to tighten the chuck) can be
inserted into one of the holes in the chuck below the ring gear
(used for tightening the chuck). This is also handy when using the
drill press to tap a hole by hand. Webb
(3824) |
| Need some hand
tools |
| I need a basic set of ball peen hammers for the shop (to be
used for auto repair, mostly), and noticed that Harbor Freight has a
5-piece set of 8, 12, 16, 24 and 32 oz hammers (39217-1RRH) priced
at $17.99. While I always purchase either German, Japanese or
US-made tools when it comes to wrenches, measuring tools, calipers,
micrometers and the like, does the quality difference, if any,
matter when it comes to hammers? Are the faces prone to chip or
shatter in normal use (punches, chisels, etc) ? A Stanley 24-oz,
Mexican-made ball peen hammer at my local Lowes is $20.00, compared
to $17.99 for the whole Chinese set. Comments? Suggestions? Also,
does anyone know the name of the manufacturer (I believe it's either
US or Swedish) of the type of wire strippers that strip all sizes of
wire from the same set of blades? This tool looks something like a
hand-held sheet metal punch. Bilal (3983) |
| I ended
up with a set of HF hammers and they look terrible. Oh well, who
really cares about the paintjob anyway. The big problem I had was
the cheap handles they came with. About the third time you whack
something the handle loosens to the point of uselessness. I ended up
replacing all the handles with fiberglass handles and haven't had a
problem with them since. Unfortunately I could have bought a nice
Stanley set for not too many more $'s than I invested in the HF's.
The thing I've come to realize is you get EXACTLY what you pay for
at HF. I still buy some things there, but I don't expect much and I
am rarely disappointed (and rarely impressed). Frank ( 3986) |
| Frank,
I think what I will do is purchase the set of Harbor Freight hammers
(the same set) with fiberglass handles. Did the ones you get come
with fiberglass handles that loosened, or were they wood? Bilal (4006) |
| Bilal, the
ones I had were wood. The fiberglass ones might not be a bad deal.
Frank (4027) |
| Shop tip |
| If your like me you can't think without your verniers. My 12" dial calipers are forever sitting out on my bench
or on the table by my lathe. And subject to becoming buried! To keep
them clean and available make an easel for them. A piece of wood
that is dug out larger then the 'footprint' of the tool and mounted
at a 70 degree angle keeps them handy and clean. The easel should
have a heavy base or screwed to the bench. If you like, get a piece
of plexi and 2 small hinges and make a cover that keeps them
protected when your not around. Thus allowing for more room in your
tool box for more important items...like a church-key. regards, Ron
BTW, the best way to clean them is to use lighter-fluid and a new
tooth brush. Scrub the rack well and blow dry. (6071) |
| How to tip
using a live center to clamp disk against headstock |
| I remember in the shop
class I took for learning to operate a lathe, one of the methods for
turning a disk was to use the tailstock with a live center pressed
up against the workpiece, holding it via friction for light cuts.
The workpiece was sandwiched between a flat disk and the flats of
the jaws of the headstock chuck. Jon (6230) |
| This is trick
I used several times. If you can take very light cuts you can use
double back taps (the film kind without the foam) and stick it to a
disc you can mount in your chuck. Marion (6388) |
| Broken tap
removal |
| Anyone have a good
suggestion on removing a broken tap, I broke one off in a spindle
bar aprox. 1/2" dia, and the tap is only about 1/8". Clint (6790) |
| Tap extractors
sometimes work, it depends on whether the tap is jammed in there or
just snapped off. Another method involves using a small punch and
driving the tap counter-clockwise with the point of the punch
catching the flute. Once you get a small amount sticking out you can
grab it with a vise grip, and unscrew it, carefully. Some taps are
hard as glass and can be broken in pieces and extracted with a
magnet. I have not done that to anything smaller than about 1/2
inch. Again it has to be a gun tap that is very hard. Hand taps are
tougher and not as hard they wont shatter. A small carbide drill
might get to it, but might worsen the situation, if it breaks off in
there. RC (6791) |
| If its jammed in
aluminum I've heard nitric acid will eat the tap and not touch the
aluminum. (6797) |
| I also read
somebody else's suggestion that sounded reasonable. Use a left hand
twist drill (opposite from normal twist drill). I believe that you
can get these from McMaster Carr or some such. Then as you're
drilling the hole (with your drill in reverse), the forces may cause
the tap to come out on its own. Dave (6798) |
| Clint MSC has those
reverse (left hand) drills; call Dallas but I think they had to
order mine from Atlanta which is 2 day UPS to us. I have a couple
but I think I ordered only the larger ones (quarter, 3/8, etc.).
About $7 each if I remember right. Lew (6799) |
| These are good for
bolts. I don't think they will work on hardened material like a tap.
Ed (6801) |
| I did a typo, it is
an ease out! Clint (6802) |
| Lurch It is steel
in steel! It is an ease out, not a tap, my typo Lew (6803) |
| Find a shop in your
area with a ram EDM. They'll get it out, but it might cost more than
you want to pay. Steve. (6804) |
| Steve, I am
planning on building a small shop built EDM and give that a try,
this thing is small!! Clint (6809) |
| Do you know of a
thing called an EDM machine? this will erode a broken stud or tap
out and leave the thread intact. Details are available on at least
one M.E. site of how to build one at home. What size is your tap? if
large you can use a welding torch to soften a carbon tap and then
drill it out. there are things called tap extractors available at
tool stores etc. Or you can try some of the other items already
suggested. pp (6811) |
| I did not
read your message to the end before I answered and you say it is 1/8
size tap, doubt you'll get a welding torch in that hole. Can you get
at both ends of the tap? or drill until you can. then use ball
bearings or hardened rod etc to allow you to grip it with a vice or
adjustable locking wrench etc and see if that will do the trick. pp
(6812) |
| PP It looks like I
will build an EDM, this thing is only about 1/8" Clint (6818) |
| The book you will
need unless you are very rich is Build an EDM by Robert Langlois
ISBN0941653 52 8 published by Village Press Inc. pp (6827) |
| Duplicator |
| I using my 9c to
make 156 walnut drawer knobs. Very slow process! Has anyone
fashioned a lathe duplicator for their South Bend? (8022) |
| I saw one for
a Taig lathe:
http://groups.yahoo.com/group/taigtools/files/Ken%20Jenkins/Duplicator%20for%20wood%20turning/ Ken was using it to make chess pieces. Dave
(8025) |
| Remove the
screw from you compound or cross slide so that is slides freely. Rig
something too hold a pattern or a prototype part. mount a follower
on the cross slide or compound and you have a duplicator. I got this
idea from a guy making Lute pegs with a small machine lathe. He used
tool steel patterns and a follower fine enough for detail. This
method scrapes and and will require sanding. I have one made by
Veritas for wood lathes that uses a round cutter ground so that it
that attempts a shearing cut but it still scrapes. Jim
(8031) |
| Grounding work
in the lathe |
| Reading
this got me curious as to how you arrange the grounding of the shaft
you are building up? I know you have to careful not to allow high
currents to pass through bearings, but haven't ever given much
thought to how you get around this in a lathe. Sounds like a useful
trick to tuck away! Stan (8057) |
| I always
fasten my ground strap right on whatever I'm welding and as close to
the weld as is comfortable. I cover the ways with old leather aprons.
With various size copper jaws, contact is not lost on the slowly
revolving shaft. I also make a lot of S/S blow pipes for the glass
blowing industry and weld them up the same way. I think if you were
to ground onto the lathe frame you would have serious problems but
as you know electricity takes the shortest easiest route of the
least resistance so once grounded to the shaft it does not go back
towards the headstock. I'm also careful not to ground to close to my
live end on the tailstock, also with the expensive Penta speed
control, it would likely be the first thing to fry if you did ground
to the lathe frame. I also apply this principle when welding on
vehicles. I never bother to unhook the battery as some do because
they say it raises havoc with the computer system. Stands to reason
if your welding on the frame or where ever that you would hook the
ground as close to the weld as possible and you will have no
problems. An old CP Air machinist used to weld on his lathe for
years so I figured he must have known what he was doing. Hope this
has been of use to you.
(8068) |
| Back pinion
tooth repair |
| Rob, there was an
article in home shop machinist, sept/oct 2002 on this subject, the
author used bronze brazing and a flux to build up the tooth, looked
pretty straight forward, all though he had access to a mill/drill I
think if one was careful to not build the tooth up to much a little
file work could clean it up. which ever way you go. rick
(8380) |
| Mill/Drill
lubrication system |
| Forgive me for
posting a mill/drill item on the South Bend Lathe group but I
believe lathe owners are just as smart as mill owners and twice as
smart if they own one of each. The only difference in the problem,
when installed on a lathe, is that almost all of the lubrication
points are observable. Let's see if you are smarter than them.
Mill/Drill lubrication system I am in the process of designing and
installing a lubrication system on my Grizzly G1006 Mill/Drill.
Dennis Armstrong's article in Machinist's Workshop, October 1999 and
Art Ekstein's ongoing project both utilize manifolds to distribute
the tubing carrying the lubricant. A machine shop owner friend has
pointed out a basic tenet of fluid mechanics; a pumped liquid will
follow the path of least resistance. What assurance do we have that
a one-shot oiler will send lubricant to the ends of ALL the tubes?
They will all be of different lengths and have varying number and
degree of bends, all of which changes the frictional resistance as
the lubricant is forced through them. If I beat myself with a stick,
I could calculate the flow characteristics based on viscosity of the
lubricant (a problematic guestimate), the coefficient of friction of
the polyethylene tubing (probably the only reliable figure available
if purchased from a good source) and the friction loss in each bend
(a wild guess at best). The pressure output of the one-shot oiler is
measurable, so that is no problem but can we trust the $4 pressure
gauge purchased at Harbor Freight? So, like most engineering
problems, we end up with an answer to four decimal places, build the
thing and than adjust for reality. BUT, we cannot observe the
activity under the tables! And, a mock-up cannot duplicate the
conditions of bends and flow from fittings, through cast iron holes
and down hand ground distribution channels in table beds. BAH!
Unfortunately, all the lubrication points in a Mill/Drill are hidden
under the tables. We get no visible feedback unless we're squirting
a shot into a single conducting tube, one at a time. Does this mean
that every tube has to be carried to a header and a Zerk fitting? Or
is the reality of the thing that the lubricant will get where we
want it to go in spite of the theoretical impossibility of it doing
so? I have never had the opportunity to examine a commercially
installed, one-shot lubrication system with multiple outlets. My
machinist friend never had a piece of modern equipment in his shop,
having purchased everything the way most of us do. Does anyone have
any hands-on experience in the successful operation of such a system? Dave
(8737) |
| You've
analyzed the problem correctly. Commercial systems use small
metering orifices of varying sizes to make sure the lubricant is
evenly distributed, since lengths of line and back pressures vary
considerably. They have a little filter and check valve in them
besides the metering hole. These orifices are mounted at the
distribution manifold, and run about $5-$10 each IIRC. Bijur is a
primary source for these, though a number of distributors carry
others. The least expensive source I know is Lube USA
1-800-326-3765. As far as selection, I think I'd go initially with
the Bridgeport design, which uses #B-2496 and #B-2495 meters,
depending on whether the feeder dead-ends in a way surface (high
resistance) or a more free flowing interface, like a leadscrew. The
check valve is a key component in these systems, since the bleed
rate is different. I'm sure that Bijur has a more sophisticated
selection process if you contact them, but it would probably require
measuring pressures and bleed rates. Mike (8740) |
| Mike I was
really pleased when Dave brought this up, and even more pleased when
you introduced both a reasonably priced source and an apparent
"standard" Bridgeport design. I have a circa 1960 Bridgeport (J
head, 42" table, 12" Y travel, base serial # ~49000) to which I
would like to add one-shot oiling. Can I simply oil into the 6
existing threaded holes where there are now grease fittings? I have
already converted to way oil, and now oil it manually through the
grease fittings (but not as often as I ought to). I understand the
newer machines have several extra oiling points for the ways, as
well as one for the nut. Do you have a copy or know whare I can get
get a copy of the "standard" Bridgeport design? Would you expect it
to be applicable to an older machine like mine? Will I be able from
the standard design to tell which LUBE USA metering valves to get?
Are the LUBE USA parts of reasonable quality? (this is an home shop
machine, so it is not going to get anything like commercial duty).
Any thoughts on how to oil the nut (I assume it doesn't have a
fitting- right now it uses the "drip through the hole" method). Is
it worth trying to oil the knee nut as well? I hope I haven't
swamped you with questions. Frank
(8751) |
| Frank, haven't you finished that job yet? vbg
talk...there's a whole list of needed upgrades that have been on
*my* shelf for several years as well...heh, heh.) There are a total
of eight feed points for both the saddle and x-y nuts on the later
machine. That's only one more than you have on the older machine. It
sounds like using your external holes would be the easiest way to do
it, if not as elegant as the hidden lines under the saddle. In
addition, there are two more feeds for the knee ways. I can e-mail
you the scan of the Bridgeport manual page that I sent to Jon Elson
over on the RCM newsgroup a couple of years ago. Just have to find
it. I know he updated his early Bridgeport with a pressure oiler and
it apparently works quite well. I don't believe he followed the
later routing exactly, though. Lube USA carries the Bijur line, just
doesn't demand as high a markup as some of the other reps I've
queried. So you'll get quality commercial metering units, not junk.
Having said that, the tubing and compression fittings will run more
than the metering units, so it isn't cheap. One of the distribution
lines in the late saddle *does* feed the top of the nut bracket. It
is jammed into a hole drilled in the top (may be the same hole that
is used for manual lube systems like yours...haven't seen yours so I
can't say for sure.) If replicating the later system proves
daunting, you might want to try a combo approach of both manual and
pressure fed. I think that's what Jon did at first. The knee
leadscrew and nut get their lubricant via the "trickle down" method
below the x-y nut bracket. I don't use my mill 8 hours a day, so I
usually augment that drip down with a spritz of way oil once a week
from an oil can. Probably overkill, but it just takes a moment.
Since I leave a 15" rotary table on the mill under the vise to get
extra mass for normal milling, the extra weight prompts a little
more concern about lubing that knee screw. You might want to ask Jon
how he did his, since he went through the thought and implementation
process. Mine was already set up, so all I had to do was change out
the clogged metering units when I rebuilt it. Mike
(8754) |
| Mike If it
s not too much trouble I d like a copy of this also. Lew (8755) |
| I have received a large number of responses from both Mill/Drill and
South Bend group members to my question and am researching methods,
sources and costs. I will post progress and conclusions as
appropriate. Dave
(8759) |
| Mike You are
right, I have been procrastinating forever on this. Every so often I
have a surge of interest, and then after some amount of activity I
get guilty about "playing with the tools" and go back to spending my
limited shop time making locomotive parts. Perhaps if I buy the one
shot oiler parts this time my inherent cheapness will make me go
ahead and spend the time installing them. I will track down Jon as a
source on converting older machines. Frank (8768) |
| I too have an
older Bridgeport, a 1952 Model, and am in the process of trying to
bring it up to newer standards. Won't, completely of course, as it's
a round ram type, but ... I kin dream, can't I? Might I ask, if
you should find it, to put me on the post list, as well? Mark (8778) |
| Absolutely.
To simplify things, I just put the Bridgeport One Shot pressure lube
drawing at *picture no longer available*. Mike (8781) |
| Mike, Thanks for
the drawing, as it clears up a lot of information for me as to how
to go about doing what I plan to do to my mill/drill. (8782) |
| Mill/Drill lubrication system update and additional question It is
gratifying that I have received more than 15 responses to my posts
on this question from both the Mill/Drill and South Bend Lathe Group
members. All had valuable suggestions. Some had in-depth experience
and some had been working on the problem already and shared their
progress. There always are six ways to design something. The final
design is a compromise of many factors. The more input available,
the easier it is to choose a good solution. I'm still waiting for
catalog and design data from three different companies. There are
some very elegant solutions already on the market but at this time,
cost is unknown. I will tabulate the alternates and estimated cost
when all the data is in. For my lathe, I have three manual pump
oilers; one each for spindle oil, heavy medium bearing oil, and way
oil. That's OK for the lathe that has oil holes that gravity feed to
the points of lubrication. I manually apply the correct lube to each
point and squirt the ways. In the mill/drill, the lubricant will go
down tubes of different lengths, with varying number and degree of
bends, most under the tables. The point of "injection" of the lube
may not permit gravity flow to the lubrication point on the ways or
screws. A one-shot oiler will probably feed a bank of miniature ball
valves that I will open one at a time to send lubricant down a tube
circuit. I think this is safer than using a grease gun that is
capable of tremendous pressure and would blow out the system if used
incorrectly. I have also looked at metering valves and orifices but
that discussion will be presented in the final report. Now the
latest question - lubricant. To be technically correct, I should
send bearing oil to the screw bearings and way oil to the ways. But
must I? I already have a one-shot oiler ($30). Do I need two? I will
be "injecting" lube into the ways, not "dropping" it on as on a
lathe bed. May I use bearing oil on the ways? If the consensus is
that a bearing lubricant is OK for both ways and bearings, shall I
use up the 15W-50 Mobil 1 sitting in my shed? (I live in
sub-tropical Miami, ergo the heavier weight oil.) Yes, I know that
the conventional wisdom is not to use motor oil on machine tools but
Mobil 1 is probably the finest synthetic lubricant made. Why not? I
have it, no longer change vehicle oil myself and the stuff is around
$5 a quart. Dave
(8884) |
| Loctite and
Bearings |
| Has anyone used loctite to set bearings? browsing the
loctite website was of little help and rather confusing. their
product selection chart has too many products. I am also concerned
about removal of the bearings in case I have to replace again. long
story: my table saw seems to have thrown/spun a bearing on the arbor
spindle. I say seems to because along with the bearings being toast,
the outside of the outer races are scored around the circumference.
I won't really know until I put new bearings in place. Housings look
ok, but one bearing came out very easily. Arbor shaft looked good.
Original bearings are ntn's, shielded not sealed. The saw started to
scream, I thought it was the motor, but in fact it was the bearings.
upon removal, the grease appears to have oozed out and covered the
seals. New bearings are contact sealed and permanently lubed. dennis
(8838) |
| I have
done exactly what you describe on a a radial arm saw that I owned a
number of years ago, and on a large surface planer about 5 years
ago. I used a product that was called (I think) "loctite stud and
bearing mount" It worked very well and bearings can be removed with
a press and a little heat if necessary.( heat gun) This product
should be available at your local bearing supply house. It may be
called something else in the US, the Loctite catalogs seem to vary a
little here in the "great white north" ( Canada, -35f last night).
Pete (8845) |
| Dennis,
Loctite does make a bunch of products for different applications. If
there is slop between the bearing outside and the counter bore, then
loctite make one that will fill a gap up tp .010. There are assembly
type and permanent types. You can debond the permanent type by
applying heat or so I am told. Hope this helps. I have the gap
filling type at home, so if you need the number, I can get it.
Tom (8846) |
| Dennis: I
have used 2 different products in the same basic situation you are
in. One was the Loctite Stud Bearing Mount which is now # 262. It
requires some heat (can be done with heat gun) for removal. The
other was Loctite Quick Metal and I can't seam to find this product
any more. Randy (8848) |
| Most likely
the top two applications of loctite are threads and bearings, it
works great. They do have so many types it can be confusing. I have
a dedicated bearing supply house I use, and I ask them for direction
in usage. My buddy had a 4WD chev and front outside wheel bearing
spun. To make it till next payday, he got new bearing and loctited
the race in and payday never came ---- he sold the truck after
another 50k miles with bearing race still locktited in. With all the
import tools we get now, its pretty common for this type failure.
Bill
(8849) |
| Dennis, As
the others in this group have already said, Loctite is a great
product. The general purpose stud and bearing adhesive is number
609. This is fills a gap up to .005" but if you need more gap
filling, you can use 680 which can fill a gap up to .015". These two
adhesives loose their bonding qualities when heated above 300 deg.
so you can remove the bearings later using a propane torch. Of
course, this will damage the seals inside the bearings but in the
future, if the bearings are already bad, .... I do wish to caution
you about using Loctite in your application. The table saws I am
familiar with, one bearing is held firmly and the other is allowed
to "float" inside its respective bore. Usually, the saw blade side
bearing is firmly held and the pulley/sheave side floats. If this is
the system your saw uses, I would use Loctite on only the one side
and leave the other bearing alone (unless the "floating" side is
badly worn; then I would add Loctite after is was assembled so that
the bearing could assume its natural position). Webb
(8850) |
| JB weld
works, too. Thomas.G. (8851) |
| I've used the Quickmetal product several times as well with great results, but now
that you mention it, I don't think I have seen it anyplace for a
long time as well. If Memory serves me , it worked best when used
with the cleaner/accelerator. Okey (8855) |
| Webb: thanks
for the cautions. No my saw does not have the floating type
bearings, they are captivated by retainers and circle clips at each
end and on the shaft. I ended up using the 680 flavor of loctite.
10ml bottle was $14. the 680 is tolerant of contaminants too. I
cleaned everything with contact cleaner first. I did not want to
spend the extra $30 for the cleaner and primer. WOW does that stuff
hold! I thought to put some on the sheave since the shaft under it
was worn and of course I had to reposition it. I was just over the
10 minute working time and I had to use the arbor press to force it
off and it was on there TIGHT. I would have to say that it seems to
have worked well. I am waiting the 12 hour cure time, so I'll find
out tomorrow. dennis (8872) |
| Absolutely! If you had waited the 12 hour cure time
before attempting to press it off, you would likely have taken some
of the hub with it...the shear strength is formidable. That's the
one thing I am always concerned about with Loctite, especially the
'permanent' ones - unless you have documented its use, you often
don't know if it's there. I removed a recalcitrant nut from a
suspension part one time and discovered most of the nut threads had
been retained on the bolt by Loctite. It wasn't one specified as
requiring Loctite in the manual, either. :-( I guess the default on
a part that is resistant to disassembly is to heat it to 300 degrees
so there's no question. That's more safely done with a heat gun than
anything - there is always a danger with a torch of getting it too
hot and affecting the parent metals involved. Don't ask me how I
know. Mike
(8875) |
| Vacuum tip for
chips - CAUTION |
| At
the risk of making a flagrant product endorsement (i guess i am) i
wanted to tell you all about a neat shop vac accessory that has been
really handy- a blue modular hose that hooks up to the shop vac. Its
the flexi blue/orange modular hose that you see on coolant systems,
only bigger. www.modularhose.com is where
I got it from. I stumbled
upon them by accident. I had never seen anything like it before. I
found that an extra foot of length in addition to the regular kit
makes a big difference as well. I can park the shop vac close,
gooseneck the hose over, adjust the nozzle near the work, and turn
on the vacuum and it will suck up everything! its been really handy.
I have been using it on the lathe, mill and in the woodshop when i
use the router too. Its been a real timesaver for cleaning up. dennis
(8973) |
| This
is one of the best tips I have ever received. This product solves
several problems that have been plaguing me for quite a while.
Jim (8974) |
| This is a
great idea for cleanup, but I am concerned about what would happen
if you sucked up a very hot chip into a shopvac with dust, etc. and
a huge moving air supply. Obviously, you risk a fire or explosion.
If you had a wet-dry shopvac, you could keep an inch of water in the
bottom, but that would probably be a mess. Anybody have any thoughts
on this issue? Bob (9049) |
| Bob: your
point is well made, and a good caution. I have never thought about a
fire inside the tank. however, I will admit that I actually use 2
shopvacs, 1 for metals in the garage and one for everything else
(wood, drywall, etc) in the house. The oils and coolant that are on
the swarf can get nasty as they coat the inside of the drum. I tried
to clean the tank out once and made a bigger mess than i imagined I
could. dennis
(9053) |
Most likely
(but not certain) the hot chip moving thru the hose along with a lot
of air would cool down before it got into the tank. I have tried
using my shop vac for this purpose but the filter gets crudded up
with oil mist. (I used to shop-vac the chip pan that also has oil on
it) I don't use my shop-vac for metal anymore - prefer a chip brush.
Explosion is a real danger with dust-collecting systems. Static
electricity can build up to huge voltages when wood dust and chips
go thru a long tube. I run a grounding wire inside and outside the
tube leading to my dust collector (which I don't use for
metalworking either) Frank
(9055) |
| Dennis, I
don't remember where (yes I do, the American Woodturner) where a guy
made an insert for the shopvac tank that would allow you to insert a
garbage bag and keep it from being sucked up to the filter. I keep
thinking I will try it for my woodshop vacuuming, but haven't yet
(mostly use a dust collector). I think it would work ok for metal
shavings. Bob
(9057) |
| Just have a
dedicated shop vac for this process!!!! No dust, etc., no
fire!!!!
(9061) |
| A fire in a
shopvac is something you need to see to believe. Flames shooting 5'
out the exit hole are etched in my memory for all time. Glad it
wasn't my shopvac or garage. I don't think that you normally get
enough particles suspended inside to cause an explosion but I
suppose someone somewhere will succeed. Ed (9064) |
| I just know
someone, somewhere is going to turn a little wood on their metal
lathe, suck up the chips, and then later suck up a hot metal
shaving, then watch out. Think about the guy cleaning out his
fireplace with a shopvac, and getting a hot coal in the mix- same
idea. I use my shopvac to clean up after everything is cool, and I
only use it for metal shavings, not even floor crud. Bob
(9069) |
| Magnesium is
the worst. I did not see the actual fire, but the damage was
impressive, and would have been worse, had it not been for a special
yellow fire extinguisher that they had there in the machine shop. I
believe they were truing up an alloy wheel rim used in testing
tires. The swarf just broke into flames. Ugly. RC (9070) |
| When you use
a shopvac in a normal way, i.e. holding the hose/nozzle tube in your
hand and running it along the floor or workbench the vac will ground
itself. What happens is that when stuff (like dust) moves quickly
along a non-conducting surface (such as the shopvac hose) static
charge builds up. But when you use it in normal way, it tends to
ground out. HOWEVER, if you have a shopvac running for a long time
with the hose off the floor the whole system is insulated and you
can get monster charges - if you use a shopvac in this way it should
be grounded separately. The best way is to run a copper braided wire
thru the inside of the hose and also along the outside, where it can
be held in place with hose clamps. then ground the wire. Problem is
that the wire inside tends to catch crud and the hose jams up. Some
woodworking places sell flexible hose with a grounding wire moulded
into it, but the real problem is surface charge. Friend of mine told
me he saw 2-3 inch sparks come off a hose. That got me religion real
fast and I don't use a shopvac as a dust collector and I've grounded
the foo out of my dust collector hose. Ed' point is well taken.
Frank (9071) |
Just
in case we all forgot - the prime ingredients of those handy little
handwarmer packets are iron chips and wood dust - a little tiny bit of
moisture and exposure to oxygen ( like AIR) is all it takes to get them
going making heat. they are supposedly self- limiting in free air but
that reaction limit doesn't hold for a confined space like a vacuum
cleaner bag or can. the next big surprise is a fun little item called
thermite - it's made up of aluminum (chips, wool, or powder) and iron
oxide. this stuff burns hot enough to weld steel train rails and spall
concrete. I am sure nobody would ever forget to clean out the chip
container after seeing a thermite burn, but just in case - you can
easily put a homebrew cyclone chipcatcher in line with your vacuum
system, to catch both the big chips and make it easier to clean up and
dispose of the catchings. you can even put a filter in it to get the
little stuff too if you want to go to that trouble. it would take a
whomper of a spark to ignite the thermite but if you had a sawdust or
steel wool fire going in there already - it would scare the ferhoodles
out of me. if you have any doubts about what may go on in that
container, think about what happens when steel wool burns - makes
plenty of heat to ignite stuff in there and to accelerate the
decomposition of wood into flammable gases. I have seen fools take a
smidgen of it and touch battery charging booster cables on it - makes a
beautifully blinding white flash and blows sparks around -also not
recommended to do. methinks there might be some fine steel and aluminum
turnings in that chip container once in a while - eh? Flames normally
(9073) |
| I am a hobby
potter as well as a hobby machinist. I once saw a burner for a kiln
made out of a garbage can and a vacuum cleaner. It was intended for
third world artisans so that coffee bean husks, peanut shells,
walnut husks, sawdust or anything that would burn could be used as
fuel. It made a very impressive flame. Glen (9115) |
| Drill press
chuck |
| I have a fairly new Delta 16 1/2 inch drill press with a
3JT taper on the spindle. The spindle runs true - I cannot detect
any problem with it. The chuck that came with the drill press is
crap. Worse than crap, actually. I finally replaced it, buying a
Rigid chuck that has a "#3 chuck taper" It's a nice chuck (old
stock, but new and a tad stiff, but very nice) but it doesn't stay
on the spindle. When I hold it on, it doesn't wobble and seems to
fit the 3JT taper, but it just doesn't stay up. What am I missing?
Frank By the way, the Delta press is semi-crap in other respects as
well. All the pulleys are slightly unbalanced. What gives with these
guys - I cannot believe that that it costs any more to cast balanced
pulleys. Same thing with my Delta 10" saw - every time I tighten the
blade it changes height a little bit. apologies for this rant, but
new Delta stuff is crap. My 1949 Delta wood/metal bandsaw is a dream
to use.
(9724) |
| Use Prussian
blue to check the area of contact between the 3JT chuck arbor and
the socket in the drill press spindle. Maybe there is a small burr
or chip at the top of the socket, where the tapered hole meets the
slot for the tang. Maybe you have some other contact problem. Jacobs
tapers are not self-releasing (9730) |
| Where and by
whom the old was made compared with the new might tell the story.
From what I have seen at a local farm store, I believe the current
tool line carrying the Delta name is imported from Asia. A lot seems
to have changed since Rockwell sold the line. Just a thought and an
observation from the owner of an old drill press who also noticed
the difference.(9736) |
| I almost
forgot! Check both the male and the female Jacobs tapers for burrs,
rust, or dirt. Both members must be smooth, clean, and dry for the
taper to seat properly. Try to stone away any nicks or gouges you
find, and completely degrease the mating surfaces. don't be afraid
to use some force to seat the taper. Rich (9737) |
| Simple
fixturing solution |
| Simple! Change the
order of the steps. Do everything else in a 3-jaw. Then use the
jig to take the last cleanup cut on the OD. Done.
(9731) |
| Okay...after
all that, we're not gonna let you get away with such a brief
explanation. If you can't center the disk in the jig because of
a .030" displacement, how can you do the "last cleanup cut"? If you
can, why use the three jaw to start with? Inquiring minds want to
know. (9734) |
| OK, what I
had been doing was blanking the parts from stock on a bandsaw, then
using the lathe to lay out the circle-and-slash to locate the
countersunk holes, then attaching it to the fixture with slightly
recessed flathead screws to face it and turn the OD, then leave it
on the fixture to go to the mill to do the graphics on the face.
Actually, the crux of it is the only one I HAD to do that way was
the sample I was working from. So now I'm blanking them on the
bandsaw, sticking them in the 3-jaw on the lathe with a spacer
behind so they stick past the jaws, facing both sides, transferring
them to the 3-jaw on the dividing head [previously zero'd to the
spindle in both axes], doing the holes and the graphics on the mill,
and THEN screwing them to the fixture to turn the OD last so there's
only one operation on the fixture and that with all the stresses
constant in one direction rather than the back-and-forth of doing
everything on the fixture. It's a bit of an inconvenience changing
tools in the mill halfway through each piece, but not that
bad...it's an old Sheldon h-mill with the dividing head set up so
the workpiece faces the spindle...more importantly they're coming
out usable. The only problems now are finish quality issues which
sharp end mills will fix. Fixturing with countersunk flatheads, even
.0005 difference in center-to-center between jig and workpiece
causes stuff to want to loosen up and walk around because the
loading on the countersinks is ...and drilling the holes on the
drill press I can't hold that tight. cut"? want Done.
(9738) |
| I
didn't understand much of it, especially in the context of the
original problem statement, but I admire the enthusiasm with which
you describe it. :-) Bottom line is you figured out a way that
worked for you, and that's about the best news anyone can relate.
Mike (9740) |
| Metal Lathe
Castings and Parts |
| I am assembling a
second SBL 9" for CNC conversion or dedicated turret. I have a bed,
headstock, bed turret, saddle and apron but no cross slide. I have
been looking at the cross slide casting offered by Metal Lathe in
Pine Grove Mills, Pa. Does anyone have experience with them and
there product line? They are offering some seemingly nice stuff at a
reasonable price but my budget does not allow a lot of gambling. Jim
(10548) |
| I have
had two of these units from MLA and would recommend them. I machined
one, and bought another pre-machined. Andy Lofquist sells ``top
drawer`` stuff!! In fact I bought a steady rest kit from him at
NAMES last weekend. I liked the t-slot x-slide so much that, when I
added a taper attachment to my lathe I built one to match that unit.
Consequently I have the pre-machined x-slide for sale. you can see
it at http://www.angelfire.com/sc3/shapeaholic/index.html and go to
the shop pages. Pete
(10552) |
| I have
finished my crosslide. It is VERY nice and the iron machines and
grinds easily. This project is a real challenge, but worth the
effort. I started with a preground casting, but next time I will buy
it plain raw. Only the top bottom is done. The grinder did not
remove enough and really removed too much from one side. This
casting is long and thin, so stresses get relieved as you go and
frequent turning and cutting/grinding each side is the way to get it
flat at the finish. I attend a tech school shop class, so have a
surface grinder big enough to finish it nicely. Andy's other
castings are equally nice. RichD(10556) |
| Not to put
you on the spot, Pete, but do you still have the pattern for the
T-slot taper x-slide that you made? The MLA-5 x-slide looks like a
good product, but I haven't bought one b/c I don't want to change
the x-slide to line-bore, then change back to cut a taper. I have
been thinking of making something similar your project. I'd be happy
to buy a x-slide or casting like that if one were available. I
wonder how many others might be seriously interested. (10559) |
| Jim While I
have never bought any of their stuff myself there has been constant
positive commentary from those who have. JWE (10560) |
| Its a nice
project. Andy's stuff is great. However, i would recommend that if
you don't have access to a mill, or the tooling required, then get
the one predone from the link on his pages. Its almost cheaper than
buying it all new. dennis
(10561) |
| Dennis, As
far as I know, the ground casting is only surface ground top bottom.
Nothing else is touched. That's far, far from done. RichD (10562) |
| Unless it has
changed look at this
http://www.statecollegecentral.com/metallathe/S-4382.html
" If you want your cross slide machined and ready to install, write,
or phone (days or evenings to 9:00 p.m.): Mr. Fred Koester Number
Nine One Eye Way Waretown, N.J. 08758 (609) 693-4613 Mr. Koester
usually has machined cross slides in stock for immediate delivery.
Write or telephone him for cost plus shipping." IIRC it was around
$150 plus shipping. dennis
(10565) |
| Jim, I have
bought several kits from MLA's collection, and ALL have been very
good values. The castings themselves are very well made and the
machining instructions are excellent. I have made several of the
cross slides, including, making one for my SB 10K, one for an old
Clausing and a cross slide for my Hardinge lathe from the casting
offered by MLA, intended for the Atlas! I have no connection with
MLA but have had great experience in past dealings with Andy Loftquist. Norman (10585) |
| I have built
two cross slides, the ball turner, the steady rest, the transfer
block and the sine plate. All sets were excellent quality, and the
resulting accessories are in constant demand in my shop. Andy is,
above all, a gracious gentleman who will help in any way possible.
Dave (10598) |
| Winding coils
|
| Anyone out there
have any experience winding coils using their lathes? I want to wind
fairly simple, single layer coils using soft copper tubing (1/4" or
less in diameter) and I am wondering if any fixtures for tensioning,
mandrels, etc should be used, also if anyone has specific
recommendations. John
(10606) |
| If you are talking soft copper around a tube or
pipe, you don't need any tension. The tension that comes from the
copper bending is pretty good. I am not sure how much or how many,
but you would put on a pair of heavy gloves and spin the chuck at
lowest speed and do it by hand. you could clamp a wooden block with
a hole and thread it if you matched the tubing dia to thread pitch.
Dave (10620) |
| Lighting a
lathe |
| I've heard many
stories about lighting a lathe with fluorescent lights, and the fact
they can make a spinning work piece appear to flutter. I see lots of
guys with workshops light the lathe work area with incandescent
lights to cut down on the optical flutter of an object spinning on
the lathe. Does anyone have any comments concerning this? Eric
(10629) |
| Yes, fluorescent is
not good, if the work piece RPM happens to be in phase with the 60Hz
flicker of the lights it can appear to be standing still. Very bad on
something like a table saw. Alex (10630) |
| Eric, I've seen
lots of posts about the "horrors" of fluorescent lights making
moving parts appear stationary. Funny thing is that I've been in
plenty of commercial shops with fluorescents and have them in my own
shop. Even when moving through the speeds on a variable speed lathe
I've never seen more than the slightest flicker if that, certainly
never to the point you could think the spindle was stopped while in
fact spinning. I do have an articulated arm incandescent desk lamp
at each lathe, not for flicker but to allow localized lighting to
peer down into a bore and such. The early tubes had a much shorter
persistence phosphor. I recall being able to check turntable speeds
by the 60 Hz flicker of the old harsh lights that had a blue tint
maybe 30 years ago. I'm pretty sensitive to flicker, can't stand a
monitor with a 60Hz refresh. Perhaps this is more of a problem in
parts of the world on 50Hz, no doubt folks that live there can
comment with fact rather than speculation from a guy in a 60Hz
country. Stan (10634) |
| I worked in Germany
and in Ireland, 50 Hz mains in both countries. The worst problem we
had with fluorescent flicker was with screen refresh rates on
computer monitors. The beat note between 50 Hz lighting and 60 Hz
monitors would give you a splitting headache in short order. I have
seen strobe effects with incandescent lighting, too. I have a lamp
clamped to my milling machine and sometimes the chips flying off
appear suspended in space in a stream coming off the mill. It's
pretty cool, actually. Glen (10639) |
| I have heard all
the stories about strobing with fluorescents, but in 40 years of
running machines under fluorescent lights I have never seen the
condition. Many industrial machines (lathes mills) come from the
factory with protected tubes in the work area directly over spinning
parts and spindles. This effect appears to be another urban legend
that should be put to rest. Rich (10652) |
| The
principle is sound but the application falters somewhat in real life,
and it occurs with all HID lights that work on the normal 60 HZ power.
Magnetic fluorescent ballasts are designed to fire the tube at 60 hz,
but most fluorescent solid-state ballasts fire it at somewhere up
around 20 khz. this reportedly makes the tube easier to re-fire and
gets good light output too for energy efficiency. It only takes a small
amount of incandescent or off-time light to defeat the 60 hz freezing
effect so unless all the lights are on the same phase- circuit and all
are in perfect condition ( no lazy ballasts firing at an off-time part
of the cycle-different from the others), the freezing is more of a myth
than reality. You can easily see the strobing effect though as a slowly
changing color or reflection from the moving part. If anybody recalls
the strobe wheel on the turntables we used to use to play LP vinyl,
these were used to set the rpm correctly. You adjusted the speed
control until the strobe strip froze in the light from the small orange
neon lamp ( or a nearby fluorescent) and you knew you were at the right
speed. This is the same principle as the freezing lathe, drill, or mill
spindle. machine spindles seldom maintain a perfectly fixed speed
because they are driven by squirrel cage motors that change speed
underload, so the speed is almost never very constant even when the
spindle is not cutting. Richard (10653) |
| I have seen the
strobe effect. it is neat with a variable speed drive. once you get
on the proper harmonics you can increase or decrease and make the
blade stand still, or even move backwards. Although I would never
imagine the shadows and related movements would lend anybody to
believe the unit was not running. It is not nearly as clear as a
timing light on a car. Dave(10655) |
|
Smaller/hobbyist mill recommendations? |
| I'm just starting
to educate myself on what's out there in terms of mills for the
reasonably serious hobbyist. Say $2k and under (ideally way under)
type of hobbyist... :-) Seems like Bridgeport is a good name, but I
don't know much of anything about them, what to look for, etc.
There's all kinds of "J-head" and stuff like that that makes no
sense to me at all. I'm also not wedded to a Bridgeport. Are there
other good quality mills I should look at? How about good quality
Chinese stuff? What features are important / not important? Seems
like there's "knee mills"? What does that mean? I've noticed that
things advertising themselves as mills seem to have a way to move
the work up and down, while mill/drills seem to only be able to move
the quill up and down? Is one of those methods better than the
other? Also seems like most mills have pretty limited y axis travel
and pretty long x axis travel... Do I need to worry much about the
amount of y axis travel? (I have yet to see a "real mill" that has
an x axis travel less than 30" or whatever...) To summarize, I'm a
mill idiot who needs to start educating himself. :-) Pointers to
newbie guides and the like are also appreciated. Mark (11070) |
| See my
responses imbedded in your text below. I recently went through this
process myself and settled on a bridgeport Series 1 J head. The best
recommendation I have on these is that they are ubiquitous and that
parts are easy to find. If you are going with a used machine, they
are a pretty good bet. They are available from less than $1000
(though if you get one in good shape for that amount you found a
bargain. [southbendlathe] decent smaller/hobbyist mill
recomendations? There are 1000's of Bridgeport's out there. For
hobbyist use, a series 1 (the smallest model) is probably the best -
it is still pretty big (around 7' high and weighs about 2000 lbs.
They come with one of several heads, the most prevalent is the J
head or the 2 J head. The J head uses a step pulley system to adjust
speed and the 2J or Varidrive head is a variable speed drive - it
ususally costs a little more than the J head and is more complex if
you have to repair or maintain. If a Bridgeport is too big for you,
you might look for a Rockwell - these are a bit smaller and have the
additional benefit of being able to break down into smaller pieces
(if you wanted to put in your basement). I have no experience with
these, but they have a pretty good reputation from what I have heard
from others A knee mill is a Bridgeport type vertical mill. The knee
is the casting that rides on the column to give you your "Z" axis.
The saddle and table sit on top of the knee. There is a good link
out there with an intro to milling that you ought to read - defines
all the parts of the machine. I will look for it or perhaps someone
on here can identify it - from a military training manual Using the
knee for Z axis gives you a longer range of motion and more accuracy
over that range. On a Bridgeport, the quill moves 5 inches, but the
knee will move several feet up and down the column (maybe 4 feet or
so). This will help with big projects. Mill drills are really a
totally different class of machine, they are much lighter and less
precise, however depending on what you want to do and how far into
this as a hobby you are one may be just fine All depends on what you
are working on. Depending on the work you are doing you may be able
to turn your work if you really have a big area to cover. (11072) |
| Mark there is a
milling machine list millingmachines@yahoogroups.com and a
bridgeport list bridgeport_mill@yahoogroups.com and
BridgeportVerticalMill@yahoogroups.com also look at
http://www.lathes.co.uk
look under popular makes and millers. archie (11074) |
| There is a pretty
active list for Clausing Lathes and Mills. You might want to lurk
there a bit. I have a Johanssen mill (company later bought by
Clausing) 24" x 6" table, about 600 pounds and about my height (5'
8"). I got it into the basement in 3 pieces with 4 friends who still
speak to me and a refrigerator dolly. Clausing still supports the
product in the same manner as our Rosie does (and I might add with a
similar pricing structure). A recent comment on the list from a
Rockwell mill owner was that parts for Rockwell mills were much
harder to find. When I started looking for a small mill, I set up
eBay favorite searches for Clausing, Burke and Rockwell. I found the
Johanssen listed under Clausing and I bought it. I am still figuring
out everything I need to do to get it in shape, but that's all part
of the fun. Glen (11079) |
| There are many
brands of mills out there. Bridgeport is sort of the standard for
many reasons. They produced two configurations of heads and a
variation on the other. The J head is the standard step pulley head.
They did produce an "M" head. It is an older style and rotates
around a shaft, like the Clausing. From the prices I have seen a
small Bridgeport cost about $1500. The 'M' head usually goes for a
bit less. Bridgeports are 'Fully' adjustable. The head tilts in and
out, rotates to drill or mill at an angle, the head can move in and
out and swiveled about the column to position the head for larger
parts. As far as the Chinese mills, the quality varies. Sharp is
probably the best. I think for the most part the quality will be ok
for the hobbyist. Usually, the imports don't hold up over the long
run as a Bridgeport. Still, in good shape they should be good
enough. They are basically clones of Bridgeport and use many of the
same accessories. That is a big plus for this category, parts and
accessories are available. Also, there are two sizes of Bridgeports.
The Clausing is a smaller mill. They are suppose to be of good
quality. They generally run on 110-120V. They would do fine as a
hobbyist mill. They rotate the head about a shaft like the "M" head.
Nothing wrong with this. Good mill for the hobbyist. The only
drawback is cost. Generally I have seen them go for $1500-1800. This
is Bridgeport range in cost. Harding made a mill. From what I can
tell very good quality. I don't know how they function though. Might
be worth a look. Again, I think they go for as much as a Bridgeport.
Others have covered some of the other mills. I think some of the
Rockwells or Cincinattis have an extra set up for a horizontal
spindle, giving you two mills in one. I don't know how this works
out though. Tree is another mill that is of very good quality. They
are heavy. The main knocks are the power feed they have doesn't feed
slow enough and the head is a bit weaker than a Bridgeport. The
collet system is nice. Sort of a quick disconnect type. I think for
the most part you need to figure out what type of work you will be
doing. Maybe one of the table top mills will do for you. Still, If
you have the money it would probably be better to get a bigger sized
mill. Tom (11084) |
| The J and M heads
with pulleys cost WAY less to repair and fail infrequently. the
variable speed heads cost big $$$ to fix when they go bad. adjust it
when if it off and then turn it on and get ready to open your
wallet. listen for any noise on those heads. Dave (11094) |
| One other milling
machine to consider is the Millrite Vertical Mill. They are a true
knee mill about 3/4 the size of the Bridgeports and clones. Earlier
versions of Millrites were made by U. S. Burke and later by
Powermatic. Current owner is D. C. Morrison and Co. Millrites are
bigger than the Clausing and Rockwell mills (but they are good ones
for hobby work too). The best thing for you to do is decide what you
want to do with your mill and then figure out how big a mill you
will need to do it with. Webb (11095) |
| I have a Millrite
vertical and can perhaps answer questions if you are interested in
this type of machine. Shane (11132) |
| I did a bunch of
reading at the www.lathes.co.uk
(or whatever) site on Bridgeports, Millrites, Clausings, Rockwells,
etc. I also took a look at the various import stuff I could see...
My goals for a mill are pretty nebulous at this point. I've used a
Bridgeport before, but my jobs are pretty varied. One day I might
need to resurface a wheel mounting hub (which is way too big for my
9C! :-), another I might need to knock off an 1/8" from a plate,
etc. It seems like a Series I Bridgeport J head would be a good
choice in terms of money and the ability to do varied jobs. Drawback
seems to be mostly just the size/weight. Looks like they're
available in the $1k to $2k range. I would assume that parts, etc.
would be plentiful. The Millrite seems interesting, but I'd need to
dedicate almost as much space to it as I would a Bridgeport. Dunno
about parts availability. This seems to be one of those "If its a
great deal" things. The various benchtop units seem to be in two
categories... Those that have a knee/jackscrew like a Bridgeport and
those that don't (are these all called Mill/Drills?). For those that
don't... Is there a way to adjust the height of the head? Seems like
there'd almost have to be... I.e. for the mill/drill at
http://www.grizzly.com/catalog/pages/416.cfm? or the ones at
http://www.grizzly.com/catalog/pages/418.cfm? Assuming I'm right
and the Mill/Drills do coarse adjustment by moving the head up and
down... Is that inherently less rigid or more prone to misalignment?
Seems like it might be... I also don't know how much I care about
power longitudinal feed... How much does that matter? Are there
types of work where its essentially required? Thanks again everyone
for helping to educate me a bit. Like I mentioned in my first
message, it'll probably be a while before I get one of these beasts,
but I'd like to know more about the various tradeoffs, what's out
there, etc. Mark (11145) |
| Mark, You might
look again at Bridgeports. There are two 'frame' or base sizes. I
don't know about model numbers etc. Basically large and small. I
think most people see the larger ones. Most people in a shop type
atmosphere want to work on the large ones. It really depends on the
work. I would say the small ones are about 6ft high (maybe less).
Very comfortable to reach the spindle draw bar. The large ones are
maybe 1/2 taller. The small ones usually have a 36 inch table. The
table isn't as wide as the larger one and have less (1 inch) 'Y'
travel. The larger mills may have a 36 inch table, 42,48 or 52. (I'm
not sure about the 36 though). Some smaller ones were special
ordered with a greater 'Y' travel. I worked in a shop that had
these. I can't remember how much more. As far as power feed, again
it depends on the work. Long slots, surfacing or fly cutting etc.
are some things for power feed. You can add this latter. I would say
for $250-500. Be warned though, fly cutting with the multi-insert
fly cutters really puts a load on these mills. I think it wears them
out real quick. Same with power drawbars. Thats one reason fulltime
shops should have a horizontal mill. One of the mills I did work on
had an after market speed controller to adjust the spindle speeds.
Work good in my opinion. One thing to remember, most of the
Bridgeport and other shop type/industrial mills run on 220V/3phase.
If you don't have 3phase, you will need to buy a converter or change
the motor. I will defer to others about converters. People do tell
me the rotary converters are the way to go, but cost at least twice.
Also, these smaller Bridgeports should cost less. I would say $1500
bare (no power feed or digital readouts) compared to about $2000 for
a full sized one. The older 'M' head would probably be $1200. Still,
look around, you might find a bargain or comb the auctions.(11148) |
| The large ones are
maybe 1/2 taller. The small ones usually have a 36 inch table. The
table isn't as Should read 1/2 foot taller. So the smaller ones are
probably 2/3 size of the larger ones. Tom (11149) |
| I am planning on
getting a Homier drill/mill for $299.00 at the next show. bench top,
not a knee mill. round column so you are correct that all your
adjustment has to be from the quill and not from the column. (boo
hiss) about Bridgeports and their clones, parts are available but
expensive. there are just too many shops that will pay top dollar
for the parts. The cheap drill/mill will be getting bed improvements
to increase the travel as well as ball screws. lapping the dovetails
will happen quickly, and Moglice in about a year. As this will
become a CNC unit, I am still going to keep my eyes open for a
Bridgeport. and for the cry in your beer on Friday afternoon, my
neighbor just bought a used Bridgeport. I told him I'd swap the 440
motor to a 220 single phase for him and wire it up if I can use it
deal. He's into cars, not machines. the cry in your beer part ?
$250.00. I offered him a quick $100.00 profit by he just laughed.
he's wanted one for years too. Dave (11150) |
| If you get a mill
without power feed and you have ANY plans to add CNC do that. it
will cost you about the same ($300.00) to add a CNC power feed to an
axis as to add a store-bought non-CNC feed. and if you have the
mill, why not ? #2) don't expect to find parts to fix one that is
damaged. by the time you find them and buy them, you will probably
spend more than the cost of a mill in better shape. I can buy a
worn-out Bridgeport for $2,000 any day, with power feeds on the
tables. figuring $500.00 for the power feeds, that is $1,500 for
machine. then figure $3,000 to $5,000 to get it ground and scraped
and basically brought back to new ways. lastly, chrome ways are
worth some extra money. you may find about half you see will have
that option. Just some food for thought. Dave (11153) |
| I got the Homier
$399.00 Mini-Mill a few months back, but haven't really had time to
do anything to it yet. I know it will need some "fixing" though. I
got it for the variable speed and R-8 spindle to drive NewWay valve
seat cutters on motorcycle heads. The table assembly is also thin
enough to fit inside a swing arm to mill axle slots. I will build a
stand to take advantage of the thin base and add flood
cooling/cutting. Also thinking, for the price, I may get another to
fix the first then turn it into a nice little surface grinder. Think
it boils down to what you really want the mill to do, and like
everything else in machining, imagination is usually more important
than equipment. Guy (11165) |
| Press Fits |
| Can anyone help me.
I need to turn a pilot bushing so that it's a press fit into a crank
shaft. I've measured the ID of the shaft cavity but I don't know how
to calculate what I need to cut my bushing OD to in order to make it
a press fit. (11975) |
| In my copy of The
Starrett Book for Student Machinists, there is a table listing
various fits including Force Fits and Drive Fits. I think the
tolerances for Drive Fit would be appropriate for your application.
But it depends on the outside diameter of the pilot bushing. As I
recall, these are slightly over one inch in diameter. Anyway the
table lists: [for 1/2" to 1" (+.0007 to +.0010)] and [for 1-1/16" to
2" (+.0010 to +.0015)]. This should give you an idea of how much
oversized you should make your pilot bushing. I would stay towards
the larger spec. of the tolerance. Webb (11977) |
| For a good press
fit you want the bushing about .0005" to .001" per inch of OD larger
than the hole you will press it into. So if the bushing is about
3/4" OD, you want the OD of the bushing about 0.0004" to 0.0007"
larger than the hole. This is really hard to measure directly. One
approach is to use some scrap brass or whatever you have to make a
plug gauge which is a sliding fit in the crankshaft hole. If you can
get it reasonably close you can judge about what the clearance is by
how easily it slides. If you mess up and make the plug gauge too
small, just try again with some more stock. Once you have a plug
gauge which is a nice sliding fit (which might be on the order of
.0005 to .001" clearance), use a tenth reading micrometer to measure
it and turn the actual pilot bushing about .00012" to .0015" larger
(about .0007" to make up the clearance and another roughly .0007" of
interference for the press fit). If your plug gauge is a very snug
fit (about 0 clearance), turn the bushing about .0004" to .0007"
bigger. It may be hard to turn accurately to this dimension (for
either the plug gauge or the bushing), even with a micrometer and a
known target. If so, turn it to within .001 or .002" and file off
the last thousandth or so. It is hard to keep it round and parallel
if you file much more than this. After you press in the bushing,
check the fit of the clutch pilot shaft. You can close up the hole
somewhat when the bushing is pressed in. If you end up with the
bushing being looser than you would like, even after all this
careful effort, buy some Loctite (one of the stud and bearing mount
variations). This will hold the bushing nicely. Frank (11979) |
| I was going to
reply until I read Franks post. I would have just repeated what he
posted. In thirteen years talking to many different people they all
agree on press fits and all the numbers Frank gave a right on the
money. Kerry (11987) |
| Shop tip of
the day! |
| I have seen a lot
of photos of lathes on this thread with exposed motors. They will
last a lot longer if they are protected from chips and cutting
fluid. When I got my lathe set up twenty four years ago, I cut a
guard to protect the motor out of an plastic milk carton. I cut a
hole for the cable to the switch and then cut a slit in the plastic
to the hole. It just snaps over the cable. I oil the motor once in a
while and the motor is still going strong Gary (12095) |
| In the shop tip I
gave yesterday I talked about making a plastic chip guard for the
motor. I should have added to make sure the guard does not touch the
motor so the air can move around. Here is another shop tip I have
not tried. A friend told me that Crisco makes a better cutting fluid
for tapping than many of the commercial ones. It is cheaper too.
Gary (12117) |
| Do you mean CRISCO?
http://www.crisco.com dennis (12118) |
| Yes, Crisco I have
not tried it yet. Hopefully my friend was not pulling my leg. Gary
(12121) |
| Crisco does indeed
work for tapping threads but it is not perfect and is not for every
type of material, it works best on non ferrous materials and mild
steels, some of the best stuff I have used outside of Tap-magic and
Kool-Tool is a cream called Edge that comes in a tube like tooth
paste, this stuff works great on very tuff materials like chromoly
and such and also works well on softer materials also. The cream in
a tube is very easy to work with and not as messy as the liquid
tapping oils. (12148) |
| We have all been
guilty of not cleaning a paint brush good enough and having it turn
stiff and useless for painting. When this happens I often cut the
bristles down to a inch or half an inch with tin snips. They make
great chip brushes! Here is another tip. If you break a HSS tap,
save the big parts and grind them for bits for your boring bars.
Gary (12255) |
| OK, and if you
break it off in Stainless, overnight in nitric acid will save the
day. Next morning, black sludge and small black chips can be flushed
out. Never mind how I know. An ultrasonic cleaner speeds the process
a lot. (12256) |
| I'm drawing a blank
on the acid, but there is also a common one that works when you
break a tap in aluminum. Dave (12257) |
| Dave, Not an acid,
hot saturated solution of alum in water. As noted, only works for
aluminum, it eats steels. There may well be an acid that doesn't
bother aluminum but eats steel, for some reason I'm thinking HCl,
but wouldn't want to swear to it. Stan(12259) |
| Broken tap in
Aluminum |
| What is the cure
for a broken tap in aluminum? (12260) |
| HCl (sold in
plumbing supply places as "muriatic acid") will react, possibly
violently, with aluminum. Alum is an aluminum sulfate (or a complex
thereof) and although I've never heard it used this way, probably
acts electrolytically. Frank (12263) |
| Aluminum is much
more electropositive than iron, and should act as zinc does to
protect it. I cannot imagine anything that would dissolve iron in
contact with aluminum and leave the aluminum unmolested. (12275) |
| Jon Yes, Nitric
Acid or Muriatic acid will dissolve the taps, etc. in aluminum. But
if it is left way to long it will begin attacking the alum. also
Clint(12280) |
| I think that any
loosing of the tap is all that is needed, not a total of dissolving
of the tap. Dave(12292) |
| I seem to remember
that when you anodize aluminum, any steels will be destroyed. since
I have never anodized aluminum and only followed threads on
different sites, I seem to remember that sulfuric acid is the stuff
used. Since I have a broken tap in an aluminum plate (6-32) I have
more than a passing interest in this right now. I'm still looking
and will let you know what I find, and how it works. Dave (12293) |
| If you can find
someone locally that does EDM the tap can be burned out without
destroying the hole or the threads that are already cut. Had the
same problem when making a sacrificial plate for a rotary table. The
tap was burned out and the hole finished. Fred (12294) |
| Dave You are
correct. Clint (12302) |
| A method I have
used if the tap is broke down far enough. Say it's a 3/8 bolt hole,
then I take another 3/8 grade 8 bolt and drill a 3/16 hole through
it. Now start it down the same hole, even if you can only get a
couple threads will do. Now put your stick welding ( 7018) DC ( 85
Amps) rod down the bolt hole, lift up about 1/8" and get someone to
snap on the welder. As soon as it arcs, give it no more than 2 or 3
seconds and quickly pull out. Squirt MOVEIT or some type of
loosenall around the bolt as it cools. This seems to draw the
lubricant down the outer hole edge. When cool turn out bolt with the
broken tap and the aluminum or threads will not damaged. (12306) |
| Another Shop
tip of the day! |
| I have junked a
number of printers over the years because they quit working or
became obsolete. Before I sent them to the dump I took them apart
and found all sorts of useful stuff. In an old daisy wheel printer I
found an 18" precision ground stainless steel bar (useful for
checking for wear on the ways of machinery). In an old laser printer
I found a 32 tooth gear that I plan on using as an index when I cut
a gear for a threading dial. In a inkjet printer I junked last
weekend I found a small dia. stainless steel rod with a screw in the
end. All I need to do to turn it into a extra small boring bar is
drill a hole near the end for an insert so that the existing screw
can be used as a set screw. I have also found all sorts of steel and
stainless steel rods that I have saved and will use in some future
project. I have a JDL 24" Engineering color 24 pin printer/plotter
sitting under one of the desks in my office. Late 1980's price new
$3000.00 today's value $0. It still works fine but there are no
drivers for it in windows, just dos. Maybe I should see if there are
any treasures in it! Gary (12337) |
| Another wealth of
treasures can be found inside old Singer sewing machines, and old
radios. My dear old uncle (radio ham, machinist, electrician) passed
on a couple of years ago and I was left all his equipment. Included
were boxes and boxes of tiny bearings and gears of every miniature
size imaginable, and hundreds of them. I guess the pack rat gene
runs in our family. I have no idea what I'm going to do with all
this (stuff) but thought maybe I would create a goofy board with one
(fancy painted colorful) gear running another and on and on and when
it finally runs the cycle it would ring a bell, blow a horn and spit
out a candy or gum drop while a hidden cassette plays a children's
song. Nothing sensible but a running maze to amaze the grand
children and their little friends. If I get it built I will post a
picture here. (12338) |
| It is hard to
fathom that you can spend $3,000.00 on a device, then 10 years later
smile that you an pull out a piece that can be used instead of a
$5.00 store bought tool. I've pulled many power supplies and shafts
and gears and motors out of old printers. makes it nice to have the
stuff, and I always laugh at what the thing cost all those years
ago. and for value, my 1932 9" workshop cost me $350.00 in 2002, and
I have no idea what the original price might have been. Dave (12360) |
| Terms - Live
Center |
| Way back when the
lathe was invented.... the term 'live center' refers to any center
in the headstock. the term 'dead center' refers to any center in the
tailstock. the term rolling center refers to a center that has
bearings so the taper can be fixed and the part contacting the work
can rotate. but... a good heat treated solid center is great to have
as is a rolling center. INHO, A rolling center that is going bad is
better than a damaged solid center. And, since I don't use a center
that often, I'd go with a cheap rolling center and use it till it
wore out. and in that time look for a good high quality rolling
center for my tool box. Dave(12359) |
| Shop tip of
the day! |
| Ever have your work
get knocked out of alignment when the tool bit accidentally took a
gouge out of the work? Instead of re-centering the work with the
chuck, try this tip. Lightly tap the revolving work with a brass,
Alu., or lead hammer. Often with a little skillful tapping and a
little luck you can get the work running true again. Gary (12582) |
| This works for any
part you put in the lathe and does not run true in the first place.
I do this when using a long shaft. If the end is not true, I'll tap
it lightly spinning. sometimes it will get worse, but usually the
hammer hits the highest spot and get it to run true. Lastly, and
this is important, after you get the part to run true and any other
machining other than a center drill, you must stop and retighten the
chuck. Dave (12624) |
| Harbor Freight
tool grinder |
| I Just received an
in-store sales flyer from Harbor Freight showing a 1/2HP tool
grinder for $119.99 (regularly $159.99) that looks like a knock-off
of a $900 grinder I see in the better catalogs. ENCO sells a Baldor
unit (without grinding wheels) for $700 and their own brand (with
wheels) for $270. These two, and the Harbor Freight offering, look
identical in the illustrations. The Harbor Freight unit has
adjustable side tables, built-in miter gauges on both sides, 2 water
cups, 2 carbide wheels 6" in diameter, a light and a cast iron base.
The set -up grinds on the side of the wheels and the tables are
tiltable. Looks wonderful, but is it? Has anyone purchased one of
these and used it? I would appreciate your input. Dave (13186) |
| I purchased the HF
carbide grinder in question last fall. It works just fine for me.
Only problem I had was the pivot screw on the miter broke loose in
the bar. Repaired it with a torch and some plumbers solder. It's
very handy for grinding chipped carbide lathe tools of which I have
a drawer full. You can only mount 6 inch plate wheels. Does anyone
in the group know of a source for alum oxide plate wheels for this
machine? Green wheels are no good for HSS bits. Mike (13236) |
| I know Hatch
Grinding wheels carry them as well as J L, Rutland and some others.
JWE (13240) |
| Building a
Chuck Thread Cleaner |
| In the 1942 edition
of “How to Run a Lathe” figure 151 shows a chuck thread
cleaner. I came up with something similar that is very easy to make
is quite cheap. I've attached a photo of the drawing in the book
with my rendition of the same tool. Simply take a torch striker like
the ones used for lighting a propane or oxy/acetylene torch (you can
pick them up for a couple of dollars at a hardware store) and remove
the spark producing portion. Bend the ends of each leg 90 degrees
and grind each to a point approximately 60 degrees. The tool works
well, but I'm not sure how comfortable I am with the metal-to-metal
friction (is it causing any damage to the threads?). This is
probably small stuff for the experienced machinists in the forum,
but maybe some of the hobbyist and newbies (like myself) will find
it interesting. Dave (13548) |
| Who was
wishing for "Blue Chips"? |
| I saw someone using
the term "Blue Chips" as some sort of good-luck wish or something.
Hmph. I guess they do not work with titanium. I was pushing trying
to finish a piece last night, and things were going well. I was
taking fairly light cuts with a TNMG Insert, and wound up with what
looked like a bunch of fine steel wool for turnings. Not bothering
to set up the soluble oil was a mistake. (MEN don't use coolants...)
I THOUGHT I saw some little sparkles at the point of tool contact,
but was tired, and shrugged them off, thinking it was reflections
from the lamp on the flying turnings. To make a long story short,
things got REALLY REALLY !!!!BRIGHT!!!!. The fire mostly burned
itself out quickly, and thanks to my cat, I had some ..err
extinguishing sand handy....but that was it for the night because I
could not see anything. The new "Titanium stars" used in fireworks
are popular for a reason! I do not machine a lot of the stuff, but
here is some free advice for the Home Machinist. I am sure the Pros
know better: Do not machine CP5 or 6-4 titanium dry at high
speeds...and do not let the fine turnings pile up. If I had the
lathe on an oil-soaked wooden bench, it would have been on the News.
CO2 and water do not put out many metal fires, they often make them
worse. Now all I have to do is clean the lathe base. Oxidized
titanium, kitty litter, catsh*t, no real harm done. (13806) |
Same result when
cutting magnesium. Very bright fire and water will only make things
worse. We have special fire retardant at work for just these
materials but I for the life of me cannot remember the name of it.
Any others on list know its name? Ron
(13807) |
| I keep a regular
fire extinguisher in my shop. Never thought about metal fires...even
though I don't do anything with magnesium or titanium probably
should have an appropriate extinguisher handy Is there any readily
available small extinguisher that is good for this kind of situation
that anyone could recommend? Frank (13809) |
| We had special
yellow "Class D" fire extinguishers for metal fires at one place I
worked but do not know what was in them. It is NOT "Dry Chemical"
ammonium bicarbonate. Magnesium burns completely to the oxide, but
this titanium did not, it left a skeleton of oxide, like a casting
of the turnings. (13810) |
| Dry sand. Not much
else works, though Class D extinguishers are available. Because some
metals burn at temperatures of ~4000 degrees or more, water or CO2
are broken down and make good oxidizers. (I KNOW this, from Work,
and look what happened to me!) One year I did a lot of magnesium,
and got rid of those turnings by rototilling them into the garden.
The tomatoes loved it. We have acid soil here, so the stuff
disappeared in a couple of weeks. I was afraid to put it in the
trash. Just don't be an animal like I was, and use reasonable feeds
and speeds and soluble oil on titanium and it won't happen. At Work
we do literally tons of titanium a year, and have never had a fire.
We have perhaps a dozen barrels of turnings going to the scrap
dealer every quarter, with no problems. (13811) |
| Believe product we
use is called MET X or METAL X for Magnesium. It is a powder in
loose form that you would just toss on to smother fire. I do believe
we have an actual Fire Extinguisher for these materials but I will
have to check its name next week when I return to work/ Ron (13812) |
| John, If you are
going to play with titanium or magnesium you really ought to
consider getting a class D extinguisher. Titanium is used a lot in
aircraft engines (GE and Pratt) I worked at both places. Its funny
stuff to cut, it never cuts the same way twice. I am not a
machinist, I just listened to them curse the stuff. Metal fires can
be real nasty to put out and then can flare up many hours later. JP
(13863) |
| Cutting
aluminum (bandsaw) |
| Can someone
please advise me what bandsaw blade I should use to cut 2-inch thick
aluminum plate? I need to cut some blocks from a larger plate and I
have a good selection of blades and an old (1949) Delta wood/metal
saw. I realize that on something this thick I shouldn't have too
fine a pitch blade, but just how coarse should I go on aluminum? I
don't have much bandsaw experience so any help would be appreciated.
Frank (14298) |
| The standard rule I
have always seen for saws is a minimum of three teeth in contact
with the material at all times. JWE(14299) |
| I use a 6 (six)
tooth per inch skip tooth blade and rub on cutting wax for 1/2" and
thicker material. Zips right thru it on a "wood" bandsaw or slower
cut off saws. RichD (14300) |
| I use a variable
tooth bi-metal saw 10-14 tpi. I believe the recommendation for a
band saw is a minimum of 3-5 teeth within the cut. I have cut 2"
aluminum with the 10-14 tooth just fine with no coolant. JP (14301) |
| I use a horizontal
bandsaw in the 14 tpi range and I lower the saw by hand rather than
let it come down by weight. If the blade slips on the wheels while
cutting dry I apply a little Relton A-9 aluminum cutting fluid and
try again. Since you are hand feeding a vertical bandsaw you can
always tell if it's cutting and apply pressure or lubricant as
appropriate. Use a low speed. -Shane (14302) |
| Question on
dies |
| Some of my dies are
marked "start from this side" for obvious reasons, other are not.
All have marks on one side type, make, size, etc. Is there a 'rule
of thumb' to start with the printed side, or on the ones not
directional marked start with either side. One more question, if I
may. I've been looking for a new/used chuck. In the catalog some are
advertised to be "semi-steel." What is semi steel and do I want it?
Larry (14326) |
| Marked or not, dies
are always used starting from the side having the initial cutting
edges chamfed back to help the die get a bite started. I've seen
them chamfered both sides too. Also, chamfer the stock material to
help get started. RichD (14328) |
| Cutting piston
retaining grooves |
| I need to cut
piston pin clip retaining grooves into pistons that did not
originally have them. (14347) |
| You could do this
on a mill or a lathe with sufficient swing. I am taking that this is
a cast piston. You can't put much pressure on the skirt or other
areas. The best place is to grip the pin bore. I would think about
making and expanding arbor for the pin bore. Long enough to go
across or into both sides of the pin bore, yet just short enough to
allow you to machine the groove from the one side. I would make the
diameter .001 under the pin bore size. Pipe plugs are very good for
use as an expander. If you use a lathe, you will need to balance the
chuck/spindle. This is for safety as well as machining quality of
the part. I might think about a plate bolted to a 4-Jaw chuck with
and arbor machined to it. I would leave the arbor over sized till
mounted, then machined to size. This way it is concentric and
perpendicular with the machining axis. Remember you must drill, tap,
and cut expanding slots for the arbor. So just rough out the arbor
to .010 over size. Then mount it on the chuck and machine to size.
Place piston in fixture and balance. 4-Jaw chucks should have some
extra slots to bolt on additional weight. Other than that, it a bit
hard to tell you what to do. Some machining is by feel. I.E. size of
machine vs. size of part and shape and what other resources are at
hand. Tom (14352) |
| Think about this
method: 1 get a spare piston pin . or use one that you have and be
careful not to score it up. 2. slide the pin in about 3/4 of the
way, so that there is enough sticking out to grip in a collet or
chuck. use loctite or CA glue to fix the piston onto the pin - make
sure you have a heat gun or solvent around to get it loose. use just
enough to hold it firmly because you will be doing this twice and
releasing it twice. if you have the patience you can use a hot-melt
glue applied to a hot pin and inserted, then heat to remove it and
use solvent to finish the cleanup. 3. grip the pin in a collet or
chuck and align the piston pin bore with an indicator. make sure you
don't score the pin if it is the one you will be using with the
piston. make up a close-fitting mandrel and use that instead if you
don't want to risk the pin 4. make a form tool to cut the groove,
you can grind a boring bar bit , or cheat and use a broken Allen
wrench ground to the contour of the groove. make sure you use a very
shallow angle but it has to be enough to let the cutting edge of the
bit actually make the cut without the tailing edge of the tool
interfering - the radius of the bore is the limiting factor here.
too steep an angle will let the tool dig in too hard and grab. you
want just enough to let it cut with the leading edge and take your
time making the cut. a little extra time spent here is a good
investment, you may want to test the tool on a piece of scrap to
make sure you have what you want because if the cut gets boinked up
you may have just ruined the whole piston. 5. cut the groove to the
recommended depth. you probably want to cut a few thou at a time. 6.
take the piston out of the lathe and reverse the pin to the other
side. this involves removing it and then setting it in the other
side using the same fixative/adhesive. 7. cut the other groove -
same procedure. 8 remove the pin and clean the bore out with solvent
to remove all traces of the adhesive. (14353) |
| Don't know how big
those pistons are, but if they are to small to use pipe plugs to
expand the mandrel, you can use taper pins instead. Just remember to
drill the mandrel all the way through so you can nock the taper pin
out with a punch or other implement. If you want to get a little
fancy you can even use a taper pin reamer on the end of the mandrel.
Taper pins are available down to very small sizes, allowing for very
small mandrels with excellent holding power. RC (14356) |
| Not knowing your
machining background or what tools you have, I'll give you a
standard process answer. If there are several pistons a fixture
should be made that will key of off the opposite side of the pin
hole. This keying pin should be less than 0.001" smaller than the
pin hole in the piston. Cutting the clip groove- -Ideally, this
would be done on a CNC mill using circular interpolation and a
cutter (like a woodruff cutter) that is ground to the width of the
groove. -Given a large enough lathe and a face plate, make a fixture
that will bolt to the face plate and the above described pin
protruding from the fixture plate toward the lathe tailstock. After
sliding a piston pin hole over the extended keying pin, clamp the
piston to the plate being careful not to distort the piston. Grind
an internal grooving tool and cut groove as any internal groove.
(14377) |
| Marking items
we make? |
| I was wondering if
the people of this group leave a symbol or marking on their work so
as to indicate to others who made the part? Etch-O-Matic has a nice
system but I have never used it, has anyone here ever used it with
good results? Does anyone have another idea as to how to identify
our items? Philip(15344) |
| Most parts I have
seen were either acid etched, or stamped with a letter and or number
punch. South Bend Lathe stamped some of their parts with the stamp I
am selling now on eBay. Richard (15345) |
| My parts are
typically instantly identifiable due to a combination of slip-shod
craftsmanship, mediocre design, and needlessly hurried production.
Now that I have a number/letter punch set I'm thinking about adding
a set of misaligned initials to each piece as well. John (15347) |
| John, et al, For
many years I have stamped "PMS" into items made for others even
though my middle name is Howard. I kinda like to call my operation
"Pete's Machine Shop". Yes, the initials are always mis- aligned
despite the best of efforts. I recall a fellow night-shift machinist
at the newspaper where I formerly worked spending many days at
various machines on some contraption or other. When I saw the
finished product cobbled together from many different bits I asked
him why he did not simply construct it from one piece and I showed
him a piece of scrap which could have easily accommodated his part.
We laughed about that often and he would come up with better
solutions to my problems than I could. It is often through the
efforts of others where our best ideas come to fruition. Do not be
deterred by lack of clear concepts, quality materials or proper
tooling, just make it! That is truly the only way to learn. Peter
(15349) |
| The etch-o-matic
marks well. You need a dot matrix printer to make fancy stencils,
the mask is a stencil. Ink jet and lasers don't work. A pencil will
work. It is an acid etch sped up by a current. Works good on hard
material that you can't stamp. You can get holders for metal stamps
to keep them in line or get a multiple letter stamp made. Using a
press rather than a hammer makes things much neater. There are also
acid pens available for marking metal. (15353) |
| I make little
telescope parts out of brass - thin tubes about an inch to 1 1/2
inch diameter. I would like to sign them, the way the old-time
makers did (they engraved their names on them ) - does anyone have
any ideas how to do this so it looks good? I can't use punches since
the tubes have to slide and tolerances are dmall. Would an etch-o-matic
work? I've never used one or even seen one. Frank (15356) |
| I have used both
the Etch-o-matic and a simple acid pen, both work well but the acid
pen is $10. The etcher worked very well in my shop for full-time use
(I used the $89 set, I think) but I think it's overkill for home use
myself. Marshall (15359) |
| Use a pantograph
and engrave it on. inch work. part? items? s (15360) |
| What is the brand
name and where do you purchase the acid pen? Neil (15362) |
| I used to work for
a small microwave company (Amerac, Beverly MA) (about 30 years ago)
We used one of these to mark our products. They were generally
silver plated Brass. The markings showed well on the silver. I don't
recall ever using it on raw brass. Jim B. (15364) |
| Would a pantograph
work if I am engraving on the side of a cylinder? Frank (15366) |
| I hope I am not
repeating something already said. There is an article in the
November 1968 issue of Popular Science explaining how to make your
own metal etching marker. In case you do not have the article, the
method is briefly described below. If it is not clear, please let me
know and I will clarify as needed. The equipment consists of a 6 to
12 volt DC power supply, an etching pad and a stencil. The power
supply can be homemade, a battery or a battery charger. No specific
current capacity was given and the author states he used a 2-amp 12
volt transformer with a rectifier. The stencil is a mimeograph
stencil and you type your mark on it. The etching pad is a pad of
felt soaked with salt water. To use it, connect the positive to the
article to be etched. Negative to the soaked etching pad. Press the
etching pad on the article to be etched with the stencil between. On
a steel article, the iron is converted to iron chloride which
dissolves a leaves a mark. Ok, the problem is where to get your
mimeograph stencils and your typewriter. I will leave that to you.
However, wax paper might make a suitable stencil material. And you
can always make your mark by hand if you cannot dig out your
typewriter. You do have a typewriter, right? ---------- + --------
Article to be etched 6 to 12 vdc power supply ---------- - --------
Etching pad and stencil P.Isaac (15370) |
| I bought my etching
pen from H C tool supply, here in Rochester, NY. I tried to find it
on their website without any luck, but I know they have it. Their
website is: http://www.hctoolsupply.com
I'm sure if you contact them they can hook you up, I think the
actual price was $8.97. It is kind of like a felt-tip marker, a
little hard to write very small, but for most jobs it's OK. Marshall
(15377) |
| Just have to get a
little creative. Make an engraving on a flexible medium and then put
it on a cylinder the same dimension as your finished piece and
engrave your finished piece. Just a thought, I have never tried it.
JP (15378) |
| The master needs to
be a cylinder the same as the work, and the two must be connected
together (roller chain, etc.) so that as you turn the work, you turn
the master. Saw an article for machine engraving revolver cylinders
somewhere that had plans for a simple setup. It was a long time ago,
and I don't know where to find it now. (15379) |
| Now that you
mention this we used to do this very thing at Amerac before we
bought the etcher. Name plates were etched on flat stock and then
rolled in a fixture and then glued to the round tubes which formed
the oscillators. Jim B. (15381) |
| Paraffin as a
Penetrating oil |
| When I need to
resort to heat to loosen frozen bolts nuts, I have found that plane
old paraffin (old candles) applied while parts are hot really
penetrates well too. (16088) |
| Has kerosene
been banned? |
| I use kerosene for
Al; it works great and doesn't leave any rust or stains. Last night
I ran out of the stuff so today, after work, I stopped by the local
Home Depot to pick up a few gallons. Well, when I couldn't find any
I swallowed my pride and asked the clerk. He looked at me as though
I'd recently arrived from Pluto then asked "What is kerosene?" I
just walked away in disbelief until I found a greybeard like myself.
When I told him I was looking for kerosene he said I would be
looking till the cows come home to roost. Said kerosene has been
outlawed by our friends at the EPA. If true, I guess I should go
turn myself in to the federales because until yesterday I've been
using kerosene on a regular basis. Is it truly true? Or, hopefully,
was the clerk mistaken? Anybody know? Anybody bought some recently?
Or, can I use diesel fuel? BTW, the Home Depot did stock nice stuff
like acetone, methanol, and MEBK. John T. |
| I just bought some
at Ace Hardware in CA. a week or so ago. |
| There's an
Ace just a few blocks from me. I should've thought of it. I couldn't
believe that kerosene would be outlawed. John |
| I buy it from the
local gas stations / Southern States. They have outside pumps for
folks who heat with kerosene. Maybe the guy was thinking of benzene.
Deodorized kerosene seems to be hard to find these days, seems HD
and Lowes used to carry it but not any longer. In any event, around
here it's running $1.49 a gallon and many stores still sell the 5
gallon blue or clear jugs for it. I think you might even find
kerosene heaters at the same Home Depot. Stan |
| Try lamp fuel. For
kerosene lamps that people use when the electric goes off. Duane |
| Kerosene is still
readily available, no reason I can think of why it wouldn't be? it
is #1 Diesel The gas station up by me sells it at the pump. Clint |
| I searched the EPA
website. I seems to be OK by them. ( Provided you monitor the CO2
level). The IRS has an issue with it. Seems that it may only be
dispensed from a pump removed from the road by such a distance that
you cannot fill up a car or truck with it or you will need to pay a
fuel tax. My guess is that you ran into a H.D. nerd. There is a lot
of that going around lately! Jim B. |
| Kero is pumped at
the local store around here. Diesel works almost a well on aluminum,
it's a little greasier and stinks a bit. Kero is #1 fuel and diesel
is #2 fuel. If you are in a cold location then diesel has additives
in the winter time so it flows easier. You may have to use fuel oil,
same stuff without the additives. JP |
| JP-5 Jet fuel is
same thing. |
| What hardware store
do you get JP-5 at?
http://www.aehs.com/publications/tphtables/43_JP-5Fuel.rtf.html
|
| Airport |
| Get Jerry-can and
go to to your local heating supply co. They all sell kero for
portable heaters Frank |
| Seems my Home Depot guy was mistaken, probably worked at McDonalds
last week. Tomorrow I'll try some "real" hardware stores. If they
don't have it I'll go with #2 diesel. I used to be a trucker, so I'm
rather fond of the smell of #2. Doubt that #1 is very available here
in So. Cal. Back in the old days when I was trucking we ran #1 in
the winter because it didn't jell up as badly as #2. Again, thanks
to all and hope y'all had a Merry Christmas and a Happy New Year
John T. |
| The last kero I got
wasn't water clear it was dyed red. I thought I had messed up and
got off road diesel, as the pumps are close. But not I fired up the
heater and after a moment to heat up no smell. Dang IRS. |
| 2-56 set
screws needed |
| Anybody have five
2-56 set screws they are willing to sell me? Larry (17376) |
| Hobby stores that
sell aircraft model kits usually have them in little bags.
(relatively expensive) I bought a whole bunch of those (with nuts),
stainless steel in a yard sale last summer. They are short (3/16"
long). Guy (17389) |
|
Fine vs. coarse thread |
|
Since this is related to machining I do have a
question. If I tap a 1/4" hole what would be a stronger fastener to
use? 1/4-20, or 1/4-28. This would be in tension - holding a lid on
a pressurized container. Any input, or where do I find the answer?
Alex I do realize going up a size would be stronger, but say you are
limited to a 1/4 inch bolt. (23794) |
|
A fine threaded fastener is stronger. (23796) |
|
To 'splain this a bit more. Think of a coarse thread
being deeper than a fine thread. It takes away more material from
the "blank" to make the coarse. because of that the fine has a
stronger body. Also, if you consider thread engagement areas for a
given thickness of material, the fine thread engages more thread and
gives more surface area, so it is less likely to strip out or pull
out. (23805) |
|
To Alex. A complicated question that will have
thousands of answers. But: The bolt that is made from Grade 8 steel
is stronger as compared to a grade 2 or 5. The # of threads has
little to do with the physical properties of the material. When
tightening the fastener, lubricate the threads and torque the bolts
properly. 9 Ft.Lbs. for the 1/4-20 and 10 Ft.Lbs. for the 1/4-28 to
achieve ~75% of the materials yield strength. The # of threads /in.
relates to the thread angle compared to the bolts axis. There are
some advantages in using more threads / in. More precise torquing,
repetitive results for multiple fasteners, and slightly more
clamping force when finished. (Grade 8 - 3250 lbs vs. 2850 lbs)
There are also some disadvantages and thumb rules. Rarely are fine
threads used in cast iron. The thread will pull out when tightened
due to the shallow root. Fine threads strip easier than coarse
threads, and because of the smaller root, the mating "nut thread"
must be more precise. If you are using stainless steel fasteners,
use an anti gall lubricant or your assembly will "lock up" and strip
all of the threads. All of the thousands of books, articles, and
experts out there will have variations of "Proper fastening
techniques" but not knowing your exact use, there are less variables
and stumbling blocks if you use the coarse threaded fastener.(23806) |
|
But you also must consider the material the threaded
fastener is being used in. For threads in aluminum or other low
tensile strength materials they always recommend Coarse (USS)
fasteners unless steel thread inserts have been fitted in which case
fine (SAE) threaded fasteners can be used. The point being made is
that low tensile strength materials need the deeper threads for
strength where on higher tensile materials the material supplies
that strength. JWE (23811) |
|
Alex, fine thread is stronger *but* that is comparing
similar materials and strengths. This is a shear problem, the
weakest. In the case of a danger situation, I would definitely use
strength rated fasteners. Most common hardware is not. Strength
grades start at 5 and 8. There are specialty fasteners that go
higher. Get the data on the fasteners and calculate the forces. Then
you know what each fastener is required to sustain including the
safety factor. Without manf's data, you can't be sure of anything. I
build small steam boilers. The dome cap uses HoloChrome or Unbrako
150-170,000 psi min screws (ASTM A-574 1960 Series). RichD (23814) |
|
Very true. I guess I was just considering similar
materials in the bolt and the female thread. (23815) |
|
I'll add to this that counterfeit fasteners are an
ongoing problem in the US. We screen 100% of our fasteners and
reject quite a few. I second the statement about Unbrako, Holochrome
or Red-Devil fasteners. These are trusted name brands for extremely
demanding applications. (23817) |
|
How do you screen fasteners? Rick (23818) |
|
Out of every box the QA dept does a dimensional
check, marking check, hardness check and at least one destructive
test (pull test) to ensure conformance to the manufacturers spec.
Only fasteners that are approved by the QA dept. can be used. It is
costly but not as costly as killing someone with a bad
fastener.(23819) |
|
Alex, if the material isn't stainless or a strange
material, you should use dry threads on the bolt and tapped hole .
Most torque values are set for clean and dry threads. (23842) |
|
I bought mine from McMaster, as you say I'm not
trusting my life to hardware store bolts. McMaster doesn't have
brand names in their catalog. Mine are from Camcar/Textron. Are
these any good? Alex (23900) |
|
One issue that arose some years back with offshore
stainless hardware was that some of it was still hot. It seems that
a lot of scrap from the former USSR was remelted without thought to
where it came from, like reactors from scrapped military vessels
etc. It was cheap and it looked good. Always had good luck from
McMaster, never any problems. JP (23901) |
|
When I seal anything under pressure, I try
to put the plug inside the bottle and let the pressure help seal it,
AND retain it. an oval hatch can fit inside of the hole, then be
rotated and the flange to flange would be under a pressure fit. If
you are talking about a typical flange where you use a nut and bolt
from the outside, then the nut must be rated the same as the bolt.
McMaster sells rated bolts. They do not list a supplier to allow
them to get a better price rate. But, if you prefer a name brand,
check your yellow pages for a fastener supplier in your nearest
city. They will offer a good selection. While there, get prices for
boxes of 100 standard fasteners. often the prices are pretty good.
Dave (23905) |
|
In general you can trust a reputable supply company
like McMasters. They buy in bulk from only a few select vendors. You
are in far more danger when the supply company (ala Home Depot or
similar) puts out a request for quote and takes the low bid
supplier, whoever that might be. There is no acceptance QA at these
stores --everything they get goes on the shelf. McMaster takes some
time upfront to pre-screen and qualify their vendors. They know that
their customers expect better than HD grade. They also know there is
some liability for them if they sell crap and it comes back on
them. (23913) |
|
Using arbors |
|
I bought some beautiful adjustable arbors from Enco
(using the free shipping code that was so kindly provided on this
forum) They arrived on Friday and when I run them between centers on
my SB 10K my B S .0001 indicator doesn't even wiggle. However, I've
never used such arbors. I will mostly use them to hold short lengths
of brass tubing. How tight do I make them? I have an arbor press -
do I press the movable sleeve tight with that? Can tubing be held
tight enough to do some fine threading on it without it slipping?
Any practical suggestions on the use of these things would be much
appreciated. Actually, they're so pretty, I hate to use them! thanks
guys, for all your help in the past! Frank (17869) |
|
Your tubing should just slip on. About .001-.002
clearance. Maybe a bit more with tubing. I was just turning some
aluminum parts this weekend with and expanding arbor I made. I would
say that threading in brass shouldn't have a whole lot of tool
pressure on it, especially with fine threads. Try tight enough so
you can't move it with your bare hands, maybe a bit tighter. You
just don't want to be expanding the brass tube. Really depends on
how thick your wall is. I don't know if the tubing you are going to
use has a seam in it or not. If so, I'd remove it. If the OD would
fit in a collet, I'd turn it that way. Tom (17879) |
|
Broken tap |
|
I broke a 10-24 tap off in the apron of my 9-C. Of
course the section which extended out also fractured easily. the
remaining section refused to do anything except bend punches. I
could move the hole and fill it in with bondo. Does any one have a
practical way of removing it even if I need to plug and redrill an
enlargened hole. I have some tungsten TIG points. Could I fashion a
crude ELOX ? What voltage and current are needed? Would a Stick
Welder work? Will HCL or HNO3 eat the cast iron at the same rate as
the tap? Jim B. |
|
It depends on the material of the tap. If it is HSS,
then good luck. I guess the tap extractor as mentioned before. Maybe
some type of acid. I think most taps today are HSS. If it is a
carbon steel tap. (I don't know the difference metallurgy wise) I
hear you can heat them up to cherry red with an Oxy-Acetylene torch,
then turn off the acetylene. This burns it out. Tom |
|
I believe the latest issue of Home Shop Machinist had
an article on this problem. I don't have the issue in front of me,
but the method described consisted of welding the broken off bit of
tap onto a suitably sized nut, and then backing the tap out by
turning the nut. For taps broken off below the surface, a length of
bolt is drilled out and the welding done "down the hole" so to speak
with a stick welder. Never tried this myself, but seems like it's
worth a shot. Tom |
|
If the work piece is one in which you have a sizable
investment in time and money---then look in the yellow pages and
find someone who does EDM. you may have to make several calls to
machine shops. In my case I found a small local shop, showed him my
part and a picture of the engine I was building. He took the part
with a broken 4-40 tap in it and in a couple of days I had it back
minus the tap and no damage to the hole or threads. It was well
worth the ten bucks he charged since the part was quite complex. Ed |
|
Starrett Center Gage |
|
I was looking at the Starrett center gage (#C391)I
bought a while back for setting up the lathe for threading. There's
more to the gage than I realized. Can anyone tell me what all the
markings are about? On each side there is a rule like part that with
4 different markings of 14, 20, 24, and 32. Then there's the
markings such as: 3 1/2 .371; and so on to: 28 .046 Then there are
the three notches and the pointed end. I believe they are all 60
degrees, but why three notches of different sizes? And the wording
"double depth of Amer. Nat. Thread", what's that telling me. Seems
funny something so simple looking has me stumped. I can read
calipers and micrometers, but not this silly small piece of metal.
I'd be willing to bet it will be much more useful if I knew what all
the other markings were all about. Dave (18541) |
|
David: # ' s 3 1/2 to 26 are the most common thread
pitches and the number beside them is the double depth of Thread for
that particular pitch ( Hence "Double Depth Of American National
Thread" ). All angles on thread gauge are 60 degrees and the reason
for different sizes is to fit different threading tools according to
pitch. The Threading Tool for a 3 1/2" pitch thread is obviously
much larger than that for lets say a 26 Pitch Thread. So you would
use the largest "V" when setting up tool to cut 3 1/2" pitch and you
would use the smallest "V" when setting tool ground up for 26 Pitch
Thread. Ron (18542) |
|
Dave, Take a look in "How to Run a Lathe" and the
machinery handbook under cutting threads. JP (18543) |
|
http://www.starrett.com
(18544) |
|
So utilizing my cross slide (on my SB each index mark
moves the cross slide .001", which cuts off .002" off the diameter
of the work), for cutting a 18 tpi pitch thread for example, the
gage says .072. Does that mean that I cut to .036" (double depth of
thread would equal .072")? number beside Hence "Double (18550) |
|
I thought the compound was to be rotated to 29
degrees, set the tool 9-0degrees to the work and use the compound to
increse the depth of the cut. After each cut use the cross slide to
back the cutting tool out of the work. Move the carriage to the
start point, return the cross slide to the original setting and then
increase the depth of cut with the compound. I THINK this is
correct. Anyone want to help out here. Eric (18551) |
|
You're right. I said cross slide, I meant compound.
(18552) |
|
Dynamic balancing on a lathe? |
|
I suspect this is a $64,000 question... Is it
possibly to dynamically balance, say, a small flywheel on a lathe? I
have a strobe unit that can be driven from a tach pickup if that
helps. The typical flywheel would be about six inches in diameter
with a 5/16" hole. I figured I could press in a mandrel and spin the
flywheel at reasonable speed (a few hundred rpm) if I could figure
out a way to spring-mount the mandrel and somehow use the strobe to
determine which way the spring mount is deflected (more deflection
equal the heavy spot?). I understand you can then apply putty to the
opposite side to see how much weight needs to come off the heavy
side. Thoughts? dave |
|
Short answer, NO! You need a compliant spindle, one
that moves. It should be suspended or mounted on matched and
calibrated springs that move in one direction and the drive
mechanism can't interfere with the movement. You also need 2 sensors
operating simultaneously. Try static balancing with a lawn mower
blade balance. I have worked with many balancing machines for jet
engine parts and assemblies and large (50') gears sed on submarines.
The concept is the same. JP |
|
It's an involved question and anything is possible
with some work...Try the "Balance" book in Victor Wowk's Machinery
Vibration series (my local library had a copy). It is insightful,
mathematically simple, and contains enough data to start
experimenting with balance. At the minimum you would need a drive
strategy that isolates the work from the headstock...a tailstock
fixture that can move with the imbalance, a master mandrel, and an
indicator mechanism to measure the deflection. dinten1 |
|
Perhaps of use, the "poor man's dynamic balancer":
http://www.antiqueautoranch.com/montana500/septnewsletter/page4.html
One fellow's approach to balancing a crankshaft. |
|
To balance a disc shaped item statically a simple
method is to use a mandrel and 2 level knife edges. A pair of thin
parallels will also work. You won't find a much difference in
dynamic balance with an item of this geometry. JP |
|
Dave, Years ago in (I think) _Marks' Mechanical
Engineering Handbook_, I copied in longhand the instructions in that
book for dynamic balancing. I think it was not printed in the next
edition. I am sure I still have it and will be happy to scan it and
email you a copy. It was not as sophisticated as using a strobe. I
think the approximate procedure was to mount the rotating part and
shaft in spring-loaded bearings, spin it, and let the throwout
motion hit a piece of chalk. This was to be done in both directions
of rotation, then add or remove weight in between the marks, and
repeat. Being a "handbook," it was not a detailed set of
instructions, but rather a general description of the process. A
standard practice with balancing a flywheel, for example, is to
remove weight by drilling shallow depressions in one side rather
than by adding weight to the opposite side. Dynamic balancing, as
opposed to static balancing, takes into account that unbalanace may
vary along the length of the shaft or rotating object. Steve |
|
Dave, Why would you want to dynamically balance a
flywheel? Static balance is entirely adequate. I do it to real, full
size antique car flywheels often. Harold |
|
J Perkins said it best. A pair of straight edges and
an axle turned to fit the flywheel. Don't try to shoot a mouse with
a cannon. There will be no discernible difference between a static
balance done as Perkins suggested, and "dynamic" balance. Dynamic
balance does not mean balancing while spinning. Dynamic balance is
for parts that have significant length compared to diameter. You
can't balance a crankshaft by adding weight at the #4 crank to
offset the weight at the #1 crank. The counterweight must be in the
plane of the unbalance. A flywheel, or a bicycle wheel has all its
unbalance in the "plane of the wheel". There is no appreciable
length to be concerned with. I, too, have had a bit of experience
with jet engine balance. About 40 years. The discs spin 15,000 to
30,000 AT IDLE, and we never saw fit to "dynamically" balance the
flat discs. Yes, we spun them, but that's NOT dynamic balance.
That's just to exaggerate the tiny unbalance so it can be found. You
can do this with your bicycle wheel too. Harold (18625) |
|
Dave As noted in previous replies conventionally
balancing is done with an isolated spindle and suitable sets of
accelerometers. However in principle the job can be done with a
rigidly mounted spindle by analyzing the vibrations induced in the
lathe structure by the out of balance forces. As the SouthBend is
belt drive and plain bearing it might be possible with home shop
resources if you can get hold of some sort of frequency spectrum
analysis or filtration gear. Basically you need three sensitive
directional microphones affixed to the head-stock structure covering
the X-Y-Z axes. When an out of balance object is spun it will induce
a vibration in the structure at the fundamental (and higher
overtones) corresponding to that rate of rotation. The magnitude and
direction of the vibration is proportional to the size of the out of
balance and its relative orientation. Obviously the lathe has its
own set of vibrations which you have to calibrate out, any extra
will be due to the out of balance you are seeking to measure. Round
about 1980 I made a gizmo of this type work well enough to sort out
the counter weighting of 3 inch diameter concave mirrors offset
relative to and angled off the rotational axis to give a high speed
nutating image when spun at about 2,000 rpm. These units consisted
of a dural mounting boss machined integrally with a thin back-plate
at approximately the correct offset angle and curved to the desired
mirror focal length on both sides. The reflecting surface was
deposited onto a glass master and transferred to the back plate by a
thin layer of epoxy resin introduced under moderate vacuum. All made
without CNC! Obviously the basic mirror is out of balance in all
axes but, if you think about it, it can be balanced relatively
simply once the various components are sorted out. I used 3 lock in
amplifiers and a four channel oscilloscope as the basic
instrumentation but there are better ways now. Having proved the
point with "lab stock" equipment the project manager bought us a
nice dynamic balance intended for turbocharger rotors which wasn't
in practice that much better except for being a whole bunch easier
to calibrate. Interesting but not a job I'd care to repeat unless
someone was paying me very well indeed! |
|
Thanks for the good advice and brief overview of
dynamic vs. static balancing. I think static balance (in a good
mandrel balanced on some single-edged razor blades) will probably do
just fine for my application -- and then some. Can't say enough
about what a neat bunch of folks we have here in this group. The
depth and variety of experience represented here is nothing short of
incredible. -dave (18632) |
|
Alright, all you Einstein out there with experience
on this thread stop talking over the heads of the rest of us and
give us some advice that us little people can use. Specifically, I
have a pulley-4 sheaves, and similar to the belt drive pulley
arrangement on certain SB lathe models- for my Clausing mill I would
like to duplicate. The actual machining doesn't appear to be much of
a problem. But on the original factory aluminum part, there are a
series of holes-about a quarter of an inch deep and with about a
1/4" drill or cutter-around the circumference of one of the pulley
sheaves on the top side over about an inch of distance, arranged
radially. Even a 20-watt like me can figure out they are to balance
the pulley, but I don't know how to do it on my homemade version.
The only way I can think of is to balance it on some sort of leveled
straightedge, taking cuts till it doesn't fall off-I know to mark the
sides-then, when it will balance, turn it 90 degrees and do the same
thing again. If any body has done something like this and has a
better way, I'll buy the beer! Bill (18644) |
|
I fly model airplanes and helicopters (well I try).
We balance props etc. with an arrangement that a rod with two cones
that screws together to center on the center hole. This we place on
two even edges. The heavy side always goes to the bottom. We sand or
shave off a bit of material to balance the blades. Not sure if this
is helps. You could call some of the automotive engine rebuilders. I
think they can balance parts. As a note, these model engines RPM
between 10K on up to 18K for a sport engine and over 30K for a
competition engine. Tom (18647) |
|
The sheave assembly is probably dynamically balanced
because of the length to diameter ratio. If you are planning to
drill a bunch of holes you might want to consider making then tap
drill holes so you can fill them with set screws if you find you
have to. First static balance it and see if it works for you.
Premature bearing wear would be the out of balance indicator and
with it not used 100 hours a week and rotating at a relatively slow
speed in ft/min then that may never show up. Balance it at the
largest diameter sheave. If you are making flat belt sheave the
standard crown is .125"/ft. JP (18649) |
|
Tom, there is a hobby shop that specializes in R/C
aircraft a few minutes from me. I will take a look at one of those
balancers. Don't feel so bad-when I was actively flight instructing
I knew a fellow who flew radio controlled aerobatic aircraft. I
after I saw the second wrecked one in his back seat one day he said
it was the most difficult flying he had ever done. By the way, his
name was Matt Chapman-at the time he was on the US aerobatic team
flying a CAP 232 and was an MD-80 Captain for American Airlines!
Bill (18650) |
|
Perk, this pulley has a bearing at each end and fits
on a intermediate shaft between the motor pulley and the pulley on
the top of the spindle. I'm hoping the opposite forces will cancel
out the need to balance it dynamically. And I'm too old to be even
thinking about ANYTHING 100 hours a week. Billkc1fp wrote: The
sheave assembly is probably dynamically balanced because of the
length to diameter ratio. If you are planning to drill a bunch of
holes you might want to consider making then tap drill holes so you
can fill them with set screws if you find you have to. First static
balance it and see if it works for you. Premature bearing wear would
be the out of balance indicator and with it not used 100 hours a
week and rotating at a relatively slow speed in ft/min then that may
never show up. Balance it at the largest diameter sheave. If you are
making flat belt sheave the standard crown is .125"/ft. JP (18651) |
|
Bill, The Quick and Dirty, Low Tech Method described
in Model Railroader Magazine 40+/- years ago for _static_ balancing
of small model rr motor armatures is to use a pair of level and
parallel single edge razor blades spaced to carry the two ends of
the motor shaft. The idea was to provide the least possible rolling
friction, with no moving parts. I have heard that Jerry White, who
built very fine-running model locomotives, dynamically balanced his
motors, but never heard about his method. I know they ran silently,
and this was the old open frame K D motors, not today's can motors.
Steve (18666) |
|
Geometric die head |
|
I recently purchased a 16" SBL and included with the
tooling is a Geometric die head (3/4" DS). Could someone help me
with finding information on how to use it? (18778) |
|
Try the following website for Quality Chasers and
look at their downloads, I think you may find some useful
information
http://www.qualitychaser.com/qc_prod.html Bill (18818) |
|
Practice projects? |
|
I just bought my first Southbend 9" and would like to
make a few things with it. Can anyone here suggest a project or two
that I can do? Also, I have a few pictures of a device I think is
for a lathe and would like to post them so someone can help me
identify it. How do I do this on this forum? Tim (18921) |
|
Yes. Your first project should be to purchase "How to
Run a Lathe" and your most important second project should be to buy
safety glasses before turning the machine on. (18922) |
|
I think I have the safety glasses figured out since I
work in the garage quite often. And yes, I purchased the first
addition, how to run a lathe from south bend. It has been a long
time since high school when I last ran a lathe and wanted a project
I could make. Tim (18923) |
|
You could start out with a set of drift punches. 1.
turning (about.005 under size) 2. knurling 3. hardening (Water
hardening rod) 4. annealing (18924) |
|
Lindsay books also has the collection of things to do
with your lathe. Probably not a bad buy. Practice projects: no such
thing really. every thing has its purpose. don't look at it as
playing. every cut should be thought out and have a purpose.
practical projects on the other hand are different. Something that
is not a production piece but valuable in learning about your
machine and machining. a simple exercise would be turning a test bar
for alignment checks. make it so you have at least a few uses out of
it. make a dummy lug for changing tires. Basically an aluminum shaft
with threads to match the threading of lug bolts on your car and an
OD to fit the bolt hole. Put stud in on as a rest to change your
tire. VW cars for example use lug bolts instead of studs/nuts. you
can make one with internal female threads for domestic vehicles. 1
1/2"X8 TPI threaded stub is another good project. Use it as a tester
for fixtures and faceplates/backing plates. Napkin rings bench block
the list goes on and on. look around at the things you use for
ideas. Dennis (18925) |
|
Tim, I have a 10 SB and my first project was a
Stirling model engine. I've made all the parts, learned quite a bit
about how not to do things and had a lot of fun doing it. I have to
leave for a couple of days but if you're interested I'll provide
more details when I get back. Norm (18928) |
|
Don't get too complicated, start simple. A good
exercise is to learn to cut a thread on a rod. Then make a nut to
fit. I felt I had accomplished something when the nut fit! Joe
(18930) |
|
How about a center height gauge? You use it to check
the height of your cutting tool to make sure it is at the correct
height. You can do your own design or make one like George Thomas's
shown in his book "The Model Engineers Workshop Manual". He also has
plans for boring tool holders, a 4-way tool post, wobbler, rule
holder, small scriber, etc. Home Shop Machinist magazine ran a
series a couple of years ago on beginner projects.
http://www.homeshopmachinist.net/ Ed (18933) |
|
Small precision lathe |
|
Can anyone on this group recommend a small precision
screw-cutting lathe suitable for small instrument parts? I have a
10k that is cherry, but too big for little stuff. Is there a
listserv for such a group? Frank |
|
Have ever thought about getting a collet
closer and a set of collets? I have a SBL with 16 inches of swing
and still manage to work as small as 1/16 of an inch in diameter
thanks to my collets. Although it would be a great excuse to buy
another lathe, I think you would be much better off with a closer.
How does the rest of the group feel about this? Philip |
|
I agree with Phillip. I have a 9" SBL. I have turned
.062 often and on occasion less and have ground .015. I see no
problem with a 10". Bruce |
|
I have a full set of 6k collets (actually lacking 2
of the 1/32 sizes) and working to 1/16 is no problem. It is the very
small stuff that gives me fits. Frank |
|
Frank A Sherline or Taig lathe might do what you
want. Neither one comes standard with screwcutting ability though.
There was or is an electronic device called the "Frog" which amongst
other things synchronizes the lead screw with the spindle allowing
threads to be cut. There are Yahoo groups for both lathes. Look for
Nicholos Carter on the Taig site. John |
|
When you mean small, how small are you talking about?
I am currently using a Craftsman lathe 12 " and I do work as small
as 0.020 dia from 1/32" round stock. If you don't have one, get a
Quick change tool post (wedge type). For small diameter, the height
of the cutting tool is very critical. My piston type tool post
doesn't give the same accuracy as my wedge type tool post. For work
above 3/32" dia, the error on height caused by the piston type tool
post is no longer noticed on the cuts. My smallest 3C collet is
1/32" and I was told you can find 1/64". If you want to go smaller,
get a real watchmaker's lathe with a cross feed carriage. (my
smallest WW collet is 0.3 mm (0.011 in). I don't believe Sherline or
Taig lathes would give you better accuracy than your 10K (Sherline
collet closer is using WW collets) Until I found a 1/32" 3C collet,
I thought about manufacturing a collet closer for WW collets for the
Atlas Lathe. 3C collets will fit no problem on your 10K. The SB no 9
draw bar fits perfectly on my 10K under re-construction It is
intended for work with collets on very small stuff. Guy |
|
Frank, My 9" SB has done everything I have ask of it.
I build small steam/Stirling engines and had no problem at all with
small stuff, 1-72 and 2-56. BTW, I use a Jacob's 59A (I think) three
jaw chuck and an AKA piston tool post. I also have a 12" Atlas that
I now use very little, I love the South Bend machine. Larry |
|
Frank I see you have been bombarded with opinions on
this one. I thought I would throw in a couple of things and you
could decide if they were of use or not. First all are correct in a
large lathe can turn small stuff but a small lathe cant turn big
stuff opinion, it is just a matter of what condition and equipment
you have in the machine. Also the convenience of a small more per
size machine is nice if you are constantly doing small stuff . I ran
into 2 machines at Richards Machinery a good while back that you
might check on or look for one. He is located in Ft. Collins
Colorado. The 1st machine was a 7 inch Medford I believe and well
tooled to do the type work you mention ( small ) He also had one I
cant remember the name of but was an Instrument making lathe very
tiny and very precise piece of equipment over 7000 used but it
looked like it could thread a hair. These tiny machines I have since
seen a couple of others but lack of interest on my part I cant give
you a name but if you contacted Richards I sure he could whether or
not he still has either machine, he is quite a nice fellow to deal
with and will answer questions honestly from my experience with him.
But like the others have stated if your machine is in good shape a
little tooling for it and it will do the job but there are machines
out there designed for just that so let your budget be your guide,
at least you can if you don't have a wife to overrule. Grumpy |
|
I guess I might as well throw my two cents in
on this one. If you are going to do allot of screw cutting, you
might want look into an old Hardinge lathe. I have a Hardinge T10
which is a 9" lathe. This particular model was only made from the
late 30s until the late 40s so they are hard to come by and parts a
tough to get but if you can find one they are beautiful machines.
Screw cutting on this machine, as well as on many of the other
Hardinge models, is a breeze. It is so much easier than other
machines that depend on threading dials for synchronization. It is
almost fool proof. You can cut threads at high cutting speeds
because the start and stop points are controlled by adjustable
stops. You do not have worry about engaging and disengaging the half
nuts while watching a threading dial. The half nuts remain engaged
the entire time and so there is no threading dial. Another nice
feature is that the spindle is mounted in a pair of precision
angular contact ball bearings so there is virtually no play in any
direction, which can be critical with very small parts. In fact
almost every moving part in the lathe rides in ball bearings.
Another option would be to look for one of the several Hardinge
copies that have come out of the far East such as Feeler or Wilton.
They look and operate virtually identically but are not made quite
to the same standards. Ron |
|
My vote would be for a Sherline with ww collets
and adapter, and the thread cutting attachment. I has cut special
screws in the 4-48 range with no trouble. Joe Smith |
|
Brass bronze stock |
|
Just bought a steady rest for my 10k/9in sb
will need to replace brass, bronze telescoping fingers. are these
available or if not where can I buy material to make replacement/
would like to make my own if I can buy some stock. also not sure if
they are brass or bronze they appear to be bronze. gregg
(19856) |
|
There was a guy selling new reproduction fingers on
Ebay although I don't see him selling right now. Finger material
should be brass not bronze. Ron (19857) |
|
On ebay I saw one steady that appeared to have two
piece fingers. They looked like they had a piece of brass on the end
of a steel rod. The fit was very close so I assume that the tip was
brazed on. Probably pretty easy to do if you have an OA welder. In
any case brass rods shouldn't be too expensive. Try Online metals. I
don't have their URL but it should be easy to find. John(19866) |
|
I believe that the telescoping fingers on SB steadies
use a special form LH thread. The guy on eBay who was selling them
them noted in his listing that he had to have the tap custom made.
If I had to refurbish the tips of the fingers, I would modify the
fingers to use bearings or maybe thread-on replaceable tips. BTW,
the originals are brass. Jeff . also not sure if they are brass or
bronze (19868) |
|
It's a small acme thread, not a commonly available
size anymore, so the tap would probably have to be made. Making new
brass fingers is the easiest way to do it. Look into
www.onlinemetals.com or
www.metalexpress.com
or McMasters, Enco or MSC for the brass rod. JP (19875) |
|
Repairing a cracked casting |
|
What is the technique for repairing cracked casting.
There is a crack near the top where the bed bots down. It is
slightly caved in. I can push it out but worried it will fall out.
It is about 5" x 3" area that is not really load bearing. I also
bought a beautiful Pedestal Delta Grinder that the casting is also
cracked more severely and I want to repair that too. (20354) |
|
If these are cast iron or steel, there are a number
of techniques for repair, most involve welding. Suggest you look
around and then ask on the welding interest groups and boards.
sample here
http://www.weldingweb.com/ check the yahoo welding groups also,
there is a lot of good info on these boards. generally - welding
castings is no beginner's task and is fraught with many problems if
done improperly so approach it with lots of information before any
action. Steve (20365) |
|
There is a cast rod that you can use that will allow
you to weld the casting cold. If you are interested I can post more
info. Scott (20381) |
|
If you need to weld cast iron the proper method is to
heat it to about 900 degrees and weld it with pure nickel rod and
then cool it very slowly. Brazing the stuff also requires preheat
and slow cool down but it is not a critical as for welding. Prepping
is also important. If it is a crack, drill a hole at the end of a
crack to stop the crack from continuing. In all cases grind out the
edges of the repair on both sides. You can use epoxy to repair non
critical sections, stuff like JB WELD will work. JP (20392) |
|
Yes, please. Is it the same stuff advertised on TV
where you can weld with a propane torch? I think it was Alumaloy or
something. I now remember them having something for cast metals too. Steve (20401) |
|
This stuff is an aluminum/zinc alloy. It is only for
use on aluminum and ZA alloys. Works very well, but a pain to apply
to castings. RichD (20405) |
|
Steve this is cast electrode designed to weld cast
without preheating. Here are two companies that make the rod. I have
personally used these rods on many occasions and they are real nice.
I just got hired by a local machine shop as there main welder and
was asked three times if I had ever used this rod. They use Eutectic
rod exclusively and do quite abit of cast welding, the owner said
they have never had a weld let go, some of the castings being
repaired are quite large from the local paper mills. I personally
think these are the way to go. If you need anymore info let me know.
Scott (20412) |
|
WD-40, something to try, it works for me! |
|
I keep my metal items clean as can be by first wiping
down with acetone/mineral spirits, then coat everything down with 3
layers of an automotive car wax. I never get rust anymore. I live in
Rhode Island where it gets quite cold, and yes, I get the
condensation also, but once you STOP the surrounding air from
touching any metal surfaces, your all set. Try it out. Philip
(20886) |
|
That is a great idea Philip. I'll give it a try this
winter, Thanks. I have to put up with temps down to -25* F in most
of my shop area. I do heat my metal lathe area to at least 40*F
.Believe it or not it does help with the tools somewhat to just keep
above freezing, easier on me too. None of the tools in the heated
area have shown any sign of rust. Must have something to do with the
dew point. This winter I plan on making my "heated" area larger and
keeping some more stuff in there. Tom (20887) |
|
Swarth |
|
What is the machinist s definition of SWARTH? I have
seen the term used repeatedly and I think I have a general idea of
what is meant from the context but I can t collaborate this with any
definition I find. From the Brainy Dictionary: Swarth (a.) Swart;
swarthy. (n.) An apparition of a person about to die; a wraith. (n.)
Sward; short grass. (n.) See Swath. Swath (v. t.) A line of grass or
grain cut and thrown together by the scythe in mowing or cradling.
(v. t.) The whole sweep of a scythe, or the whole breadth from which
grass or grain is cut by a scythe or a machine, in mowing or
cradling; as, to cut a wide swath. (v. t.) A band or fillet; a
swathe. Swart (a.) Of a dark hue; moderately black; swarthy; tawny.
(a.) Gloomy; malignant. (n.) Sward. (v. t.) To make swart or tawny;
as, to swart a living part. Sward (n.) Skin; covering. (n.) The
grassy surface of land; that part of the soil which is filled with
the roots of grass; turf. (v. t. i.) To produce sward upon; to
cover, or be covered, with sward. (21433) |
|
Its swarF, Fine metallic filings or shavings removed
by a cutting tool. (21434) |
|
I think you mean swarf, pretty much the only people
that use this term are newbies and real real old timers, most
professional toolmakers or machinists will call them what they are,
chips. I hate the term swarf, it sounds so silly and does not really
give any indication as to what it is but metal chips does! I have
been working as a tool and moldmaker for 23 years and have never met
anyone that calls it anything but chips. (21437) |
|
I have heard it called a lot of things that can't be
posted here when it gets into where isn't supposed to. JP (21444) |
|
Swarth is the trash accumulated in various corners of
a machine composed of chips, oil and dirt. (21447) |
|
The term is miss-spelled the actual word is ' Swarf
'. It refers to the turnings produced when machining metals on a
lathe. Terry (21449) |
|
I noticed Mr. Ruffin's reply and would like to say
that Swarf, chips or chippings are acceptable. Chips or chippings
tend to refer to the turnings from brass or cast iron as this comes
off as small bits of material, whereas swarf tends to refer to steel
as the turnings tend to come off as a continuous length if the tool
is correct in sharpness, cutting angle of the tip, the angle it is
presented to the job and suitability of the tool for the material
being turned. Terry (21452) |
|
Cast iron surface prep |
|
I have my SB heavy 10 apart and am finishing cleaning
and readying for paint. I am wondering if anyone has any suggestions
on a good surface prep for the cast iron, in order to smooth out the
poors in the cast iron before final paint. Someone suggested an
Evercoat product, but I can't recall which one? William (21739) |
|
Get a good respirator and wear it. RC (21752) |
|
There is a paint called glyptal that works fine. Get
it at Eastwood auto finish suppliers or some others. Google it to
find if you have a supplier nearby. This used to be commonly applied
in the electrical industry as machine and motor insulation, now also
used for sealing cast surfaces. You can use repeat coats to get the
finish build of your liking - each coat gets a little smoother but
usually only takes one or a very few to get rid of most all the
pores. Continue coating to get a very built up and sandable-smooth
finish if you are looking for a look that says it is polished smooth
under the paint. William (21781) |
|
Tolerances |
|
Having cut stone with tools that match Michelangelo's
I find it not difficult at all to match the same precision. Any
well-trained stone-cutter should be able to do this if he's any good
at it. I'm glad you brought this up. My whole point was, it's not
the tool so much as who wields it. Those stones were square to the
corners once. I daresay they probably had a dull sheen for finish as
well. They were either basalt or granite, (I forget which). All
these people had was some real good stone to work with, patience and
time, lots of time. They used hardened bronze tools. They had heat
and could bore holes that could then split the rock from the quarry.
But let's cut to a real OT. Question to all. How did the Trillithon
Stones get moved to their final resting site at Stonehenge? Please
reply off-list. Not everyone here is into Bronze Age engineering.
Back to hardened ways and such. I have no quarrel with them. But
consider how much of a pain it was to do them. You see, when you
grind any kind of metal, the first thing it does is expand. If you
took shop you know what a crater a surface grinder leaves if you
grind without water. It's not much better with coolant. There is
still a hole. So if your making a lathe with hardened ways you will
be grinding and or scraping, or have a real cute process that avoids
this physics problem. Hardened ways are great, until you have to
re-do them. THEN it gets real expensive. That's why the old farts in
engineering came up with the idea of accessibility. The idea being
able to re scrape the ways whenever they need it. You can't do that
with hardened ways. You toss them and buy new. See, that the other
point I was trying to make. Just because it's old, you don't chuck
it. Ron (21845) |
|
Hardened ways do not have to be flame hardened, they
can be induction hardened, scraped for oil and then induction
hardened, for hobby use they would never wear out. Grinding the bed
of a lathe nowadays is child's play and far more acurate for the
money and time spent than conventional scraping. As far as scraping
a hardened bed to resurface it, you just regrind it and scrape it
with diamond tools and call it finished. If I ever get my bed redone
it will be ground and then hard chromed, that will outlast me or
anyone that inherits it. Modern grinding techniques are rocket
science compared to even 5 years ago let alone the 1940's when are
lathes were made. I have ground lots of large surfaces flat and with
a far better surface finish then the best scrapers could get, as far
as grinding craters that's a relative term, if you burn it yes you
will get sunken spots but that is not common. A good grinder should
get the finishes way down in the micro inches finish. (21851) |
|
You are dealing with grey iron, not tool steel. Grey
iron has a unique damping that no other material possesses and is
ideal for machine tool foundations like lathe beds. Finishing is
generally done with carbide scrapers and hardened ways can be
scraped. Contrary to your assumptions, professional hand scraping is
still the most accurate finish for machine tool bed ways. Diamond is
never used on a cast iron wear surface by knowledgeable
professionals. Cast iron has a coarse matrix and the diamond
particles easily embed themselves into it. If you are looking to
grind to a micro inch finish then you need a micrograin structure to
grind, not cast iron. While induction heating is common, material
properties and part geometry dictate how a part can be heated and
quenched for hardening without setting up internal stresses which
can cause part failure. JP (21852) |
|
I have followed this thread with great interest. My
lathe bed is a hardened and ground type but I do appreciate the hand
scraped beds too; maybe even more so. Although hard beds have the
advantage of being longer wearing, I wonder about warpage of the
casting. If a bed isn't fully seasoned or incorrectly clamped
inducing some stress when being ground, then you will not have a
"straight" bed. Some companies were good about seasoning their
casting before machining but even a well seasoned bed can sag under
its own weight over time. Generally, this usually happens to very
long beds on very heavy machines and where the design didn't provide
for adequate support of the bed. Now most of the rebuilders grind
lathe beds now but it seems they scrape the saddle to fit. So, I
think there is room for both technologies when it come to
rebuilding. Webb (21856) |
|
What you seem to be describing one of the differences
between the older American made machines and the new counterfit
imports. Many of the older castings were well seasoned and then
roughed on a planer or scraper and then hand finished. As time went
on (after 1950) artificial aging was done and still is in some
industries and then grinding. Heat treating falls in there when
applicable. Unfortunately, quality has given way today to the quick
buck almost everywhere. JP (21857) |
|
Grey iron can be ground just like any tool steels,
different wheels are needed. I know I have ground several large
parts made out of grey iron. Diamond chisels could be used to scrape
the oil channels, as you are using solid industrial diamonds not
files with small particles. And yes you can get as good as or better
finish from grinding a course open grained structure like grey iron
than scraping them by hand, especially when you consider the cost.
Grey iron while difficult to grind with normal wheels can be ground
with certain ceramic wheels quite easily so long as there is coolant
applied. Induction heat treated parts are not quenched when hardened
and stress's can be controlled to some degree by the depth of the
hard surface. (21858) |
|
Is a hardened or unhardened bed a better choice for
regrinding? I have a heavy 10 with a hardened bed on a cabinet base
that I am considering getting reground. I also have a heavy 10 parts
lathe with an unhardened bed and cast iron legs. Both beds are
heavily worn. I assume that the hardened one is a better choice
since it would be more durable. Or is only the surface hardened? The
longevity probably doesn't matter much since either will almost
certainly out live me anyway. For that matter, can I swap them or
are they in some way unique due to the different base style? I am
planning on using swapping the saddle since the older one's cross
slide is in much better condition and it is already fitted with a
taper attachment. Any issues here assuming I have it scraped to fit
the reground bed? Ed (21863) |
|
Your best bet is to have the outfit who will do the
work check both and give you a qualified answer. I believe the last
part of the serial number stands for the lathe revision. You may be
able to get info on the differences from that. JP (21864) |
|
Why 'engine' lathe? |
|
For the benefit and enlightenment of any of us
Limeys who are ignorant, where does 'engine' come from please ? Tim
|
|
As in 'engine lathe'? I'd guess it comes from the
primary purpose at one time being the machining of steam-engine
parts. Lurch |
|
To distinguish these "modern marvels" from those
powered by hand or human power. Perhaps even to distinguish them
from those powered by water wheels. Scott Logan |
|
My understanding is that it refers to the fact that
the lathe was operated by power, (i.e., an engine) as opposed to
hand or foot. Greg |
|
Long, long ago; the machines were in factories
located along streams and rivers, and through a complex system of
gearing, and overhead shafting; individual machines could be
appropriately powered by a water-wheel. With the arrival of the
steam engine, the factories could now be located anywhere. They
retained the gearing and overhead shafting, and now the machines
became engine-driven. Hence: Engine Lathe. Joe |
|
Any piece of mechanical equipment has had the name
"engine" applied to it in English ever since manufacturing (as
different from craft work) began. Way back in history there were war
devices called "siege engines". Also, quite often, this would be
shortened to "gin", as in "gin block", "cotton gin" and "gin trap".
It's really nothing to do with what drives the thing, just that it's
a mechanical device. Len |
|
For that matter, what the heck is a 'fusee engine'?
Is it related to a lathe? applied to it in English ever since
manufacturing (as different from craft work) began. Way back in
history there were war devices called "siege engines". Also, quite
often, this would be shortened to "gin", as in "gin block", "cotton
gin" and "gin trap". It's really nothing to do with what drives the
thing, just that it's a mechanical device. |
|
Its an engine used to make fusees' what else
http://www.angelfire.com/sd/rronnie/Fusee.html Watchmaking part.
JP |
|
In itself its a sort of lathe for making a clock part
called a fusee which I believe equalizes the timekeeping as the
spring unwinds. Len |
|
There's a third possible source: the 'engine' refers
to the gear train and lead screw of the Maudslay-origin metal lathe,
this in contrast with manual lathes, such as those used in
woodturning, or the kind of metal working lathe without powered
feeds. Can't say where I heard this, but I didn't make it up myself
;-) This fits with what someone else said about any sort of
mechanical contrivance of sufficient complexity being called an
"engine" in old usage. (The term has been granted extended life by
the NerdWorld, now referring to software that performs a certain
task, as in "search engine".) Dave |
|
I like that explanation better than mine. I think
I'll keep it! My understanding is that it refers to the fact that
the lathe was operated by power, (i.e., an engine) as opposed to
hand or foot. |
|
Doesn't "fusee" refer to some type of escapement used
in clocks? Greg |
|
I've read, with interest, the many comments on the
subject. I support the "powered" meaning for "engine" and offer the
following in support; In Mine Hoists (one of the earliest
applications for the steam engine), when the brakes and clutches
were too big to be manually operated, the steam cylinder for the
main brake was and still is still referred as the "Brake Engine"
Likewise the clutch actuator is referred to as the "Clutch Engine".
By all rights this should initiate a comment from Scott Logan who
will also be aware of this connection. Jim Waugh |
|
That does not explain the long usage in English of
the word engine to describe any mechanical device. In fact the word
comes from the latin "ingenium" meaning a talent or a device
(obviously where we also get ingenious from). The word engine was in
use in English for centuries, long before it was applied to a power
source. Len |
|
As Far as I can tell the term 'engine' refers to any
apparatus that results in 'work being done', or any apparatus built
to perform a purpose regardless of the power source, be it
electrical, steam, fuel, mechanical or Manual (hand powered). That
is why it can be used in descriptions going back so far into
history. For example a rope pulley system on an 'A' frame could be
described as a lifting engine, and that sort of 'engine' can be
dated back as far as history can go I guess. The term 'Engine lathe'
is defined in the Oxford English dictionary as :- a turning lathe in
which the cutting tool has an automatic feed; -- used chiefly for
turning and boring metals, cutting screws, etc. Terry |
|
I am reminded of a reference i saw once about a
letter written by Napoleon to a friend of his asking for some
"engines of prevention used by gallant and prudent gentlemen"--in
other words, condoms. Lurch |
|
I thought the object was to reason why the word
"engine" was appended to the word "lathe" and in my e-mail I gave
another historical example to support my opinion. So I have just
returned from our local library having consulted the multi-volumed
Oxford Dictionary "engine-lathe, a lathe worked by machinery" and
the three volume Webster's "engine-lathe, a screw-cutting lathe
equipped with a back-geared cone driven headstock or a headstock of
the geared-head type" Sorry for quoting only etymological
references, the library was closing and I did not have time to
consult an encyclopedia. However I still have the opinion that it
means an engine (powered) lathe as opposed to a manually powered
lathes and I don't think it need be equipped with either back gears,
cone pulley or even be capable of screw-cutting. Jim Waugh |
|
I understand 'Engine lathe' to be a lathe powered by
its own independent engine as opposed to a line shaft driven one. I
don't believe lathe options are relavent, only that the engine
somehow rotates the spindle or workpiece. JP |
|
Don't know why I didn't immediately consult the
source, normally acceptable to most of this group; namely: HTRAL.
You will find it on page 3 under History of the Lathe. Jim Waugh |
|
Math |
|
I never was very good at trig. I need to cut a
26 tpi for a 3c collet draw-in tube. What's the depth of compound
feed for a vee form tool for 26 tpi? All the charts I have seem to
skip 26 tpi. Secondly, where did 26 tpi come from as a thread for 3c
collets? Alan (23958) |
|
Single depth of thread is .0249. Double Depth is
.0499. Feed depth of compound set at 30 degrees is .0288. Why 26
TPI?(23959) |
|
I have been trying to figure this threading stuff out
but can't find any information that explains it all and gives all
the formulas. And worse yet, different sites give different formulas
(or at least different constants). What I have come up with so far
is (assuming P = 1/TPI) : For external threading with a straight-in
V tool, the thread depth is P * .758 and I assume this is the actual
depth and I don't have to divide that depth in half when feeding.
For internal threading, the thread depth should be P * .65 Now when
it comes to feeding with the compound at 29.5, I get lost. I'm also
not clear what is meant by double depth. Could anyone clear this up
for me? Kevin (23962) |
|
Feeding the compound set at 29.5 deg by 0.1"" will
advance the bit 0.08704" but will cut on both sides of the part so
will reduce the OD by double. Please check to confirm. I did a quick
CAD layout with the angles and measured from that. It would be easy
to turn an OD to 1" and then only using the compound, to move 0.1"
on the dial and see if the OD reduced by 0.17408" Dave (23966) |
|
Al Costich writes: I never was very good at trig. I
need to cut a 26 tpi for a 3c collet draw-in tube. What's the depth
of compound feed for a vee form tool for 26 tpi? All the charts I
have seem to skip 26 tpi. Not wanting to bother with the math myself
at this time, look up the value for 13 TPI and divide by 2.
Secondly, where did 26 tpi come from as a thread for 3c collets? Ask
Hardinge, the originators of the Cataract series of collets (that's
the xC series). Presumably it has to do with wanting a minimum depth
of thread so as to allow maximum clear passage through the collet
within a certain form envelope. I'm attaching a GIF of the 3C
adapter which includes the info on the drawbar thread (I presume
it's the drawbar that concerns you). Anthony (23967) |
|
There may be a simpler explanation. The Hardinge
brothers were Canadian. 26 tpi is common in the British Whitworth
system. Ask anyone with an old British bike- the cases are joined
using 1/4-26 screws. Do the collets have 60 degree threads or 55
degree? most Whitworth threads are "sharper." To cut Whitworth, set
your compound at 27 degrees- 30 degrees will cause the peaks to go
sharp before you reach the correct root diameter. All of this is
from memory but I think it's right. Bill (23971) |
|
There is a Thread Depth Guide in the files section.
JP(23987) |
|
Calipers cost? |
|
In order to properly setup and adjust my Southbend I
will need to pickup a caliper. What is the approximate cost for a
tool that I will probably be using most of the time? Digital or
Dial? Rick (23979) |
|
You can pick up an OK one for about $20, a dial
caliper made in China. I think the Digitals go for about $40-50,
made in China. I like my digital Starrett better than my Mitutoyo
Dial calipers. A bit more accurate and the chips don't get in the
gear tract. Still, the Starrett are about $130-150. I think a USA or
European dial caliper is the same cost. Calipers are generally + or
- .005 thousands for accuracy. I think the digitals do better and
others can get better accuracy from dial ones. Also, verniers are
good. A bit better accuracy than dials and better durability than
both. They are harder to read though. Probably for what you are
going to do, a $20 set will be OK. If you could find a set made in
Poland or any former Eastern Block country, then they are of better
quality than ones made in China. But they will cost a bit more. I
base this on the micrometers I have used or handled and bought. Tom
(23981) |
|
I have one of these and like it.
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47257
Here's it's big brother
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=47261
They also have a large readout one. Joe R (23986) |
|
Machining Definitions (British?) |
|
I'm looking at some projects posted at
http://easyweb.easynet.co.uk/~chrish/homepage.htm about
some definitions of some of the terminology. Not sure if the terms
are foreign to me because of the British site, or because I'm such
an amateur.... PCD (pertaining to the diameter of something) bms
(type of steel?) F/C (free cutting steel?) DTI (something pertaining
to measuring a taper) Silver steel (what kind of steel?) BSF thread
(British Standard, or something?) Free cutting steel (what kind of
steel?) Case hardening steel (vice free cutting steel; I understand
what case hardening is, I'm just not sure what kind of steel this
is) There were a few more, but I can't remember what they are at the
moment. Has anyone purchased any kits from Hemingway Kits
http://www.hemingwaykits.com/ Does anyone know of a distributor
in the states? Dave (24101) |
|
Like the saying goes, two countries separated by a
common language. Pitch Circle Diameter Bright Mild Steel. Basically
any cold rolled steel, as opposed to hot rolled. Yep, Free Cutting,
such as 12L14 Dial Test Indicator Over here, we call this Drill Rod
British Standard Fine, a thread specification As above, something
like 12L14 or even 1215 Something low carbon, such as 1215 or 1018,
which does not through harden. Scott S. Logan (24103) |
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Dave, I think silver steel is what us rebels call
stainless steel. Free cutting steel here in the us had lead added
into it. It helps the machinabilty. The code would have an L in it
such as 17L18. Case hardened steel is a low carbon steel. about 20
points. 1018, 1718 etc. 8620 is a very good steel to case harden and
it machines well. BSF (British Standard Fine thread ???). Probably
like UNC and UNF. 'bms' guessing again 'b' ?? 'm' mild 's' steel. If
so then 20 points of carbon possible up to 30 points of carbon. Tom
(24105) |
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Dave, In one of the articles they list silver steel
as drill rod. Tom (24106) |
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I've added in some answers to the ones I know off the
top of my head in italics...but anyway, if I recollect correctly,
somewhere on Chris Heapy's site is a glossary of abbreviations.
leastwise, last time I looked which could be a couple of years
back... Len (24107) |
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Dave, Hemmingway does have a reputation for quality.
I find the VAT and shipping from across the pond can add
considerable to the total price so check it all out. I have not
ordered anything there as a result. I don't know of any US
distributor for their complete line of kits. I communicated with
someone there a year or two ago and it seems that sales is now a
part time, low volume business. At least that is the impression I
got. JP (24108) |
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If I'd done a bit more investigating, I'd probably
found most of my answers on his "Techniques" pages. I apologize for
my lack of more investigating. You guys are awesome! Thank you! One
of the things I love about this forum (beside the awesome knowledge
base) is no one looks down on even very amateur guys like me. Dave
(24109) |
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Repeated contact with lead can cause it to build up
in your body, some people are more sensitive to it than others.
Industry is getting away from using lead. Bismuth is used and causes
the steel to free machine like the leaded stuff. The 10xx series
steel is as milled, the 11xx is 'resulpherized' and the 12xx is 'resulpherized
and rephosperized'. Basically what is done is adding a controlled
amount the sulpher and phosphorous to a tighter spec. It makes the
material machine better and result in s nicer finish amongst other
things. On case hardening most any steel with low carbon, .3% or
less doesn't harden up well so carbon is added to the surface with
something like Kasenit. The outside is very hard and the inside is
softer and the unit is capable of taking impact without breaking
apart. Aloris tool holders are 1117 steel, case hardened .02". They
are strong and tough but are east to machine, take a nice finish and
plate well. JP (24110) |
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The only thing I can add to Scott's definitions is
that silver steel at one time did include Silver. At least this is
what I read in Henry Bessemer's autobiography (free eBook). It was
only mentioned in passing though with no details. Apparently it was
developed in the early 1800's and used for such things as razors,
cutlery, etc. Current references indicate it is similar to drill rod
and is a carbon steel without any actual silver. John (24115) |
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You shouldn't have to pay British VAT, it's
applicable to UK residents only. The vendor, in this case
Hemmingway, just has to fill out a VAT exemption form. Last time I
was there it was 17.5%, so it's worth asking them. As a matter of
interest, I didn't find shipping too bad, when I moved here from the
UK I was looking for a 12" table saw and lathe and the prices I saw
made me investigate buying and shipping both from the UK. I ended up
with a 12" sliding table Wadkin saw and a fully tooled Heavy 10, on
original cabinet. The cost including shipping put me ahead by at
least $1K. BernardR (24123) |
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AFAIK if you are an overseas buyer, ie not living in
the UK, you DO NOT need to pay the VAT. Could be worth checking out,
if you have paid VAT and not needed to, you just might be able to
get a refund (maybe?). I believe that some time ago visitors to the
UK could obtain VAT refunds at the airport for goods on which they
had paid VAT. (I live in Western Australia so I'm not the best
authority on this. Peter (24129) |
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DTI Mounting |
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Mounting a DTI to measure work piece eccentricity can
be a pain on the smaller SouthBends as there are no flat, smooth
surfaces on the bed or cross slide of a suitable size for the usual
mag-base DTI mount to get a decent hold of unless a long, T-slotted,
cross slide has been fitted. On my Heavy 10 I eventually milled a
small portion of the guard flat so that the mag-base could get a
proper grip. I've also resorted to hanging the fine-adjuster arm off
the chuck guard mount. Eventually the penny dropped that there was a
better way. For the last 15 or so years I've used a drill chuck
mounted holder for my Verdict lever DTI when aligning things on the
milling machine. Works great in the lathe tail stock chuck too! Its
depressing to consider how many choice expletives and comments I've
wasted over the years. My DTI holder is the swish deluxe one with a
short dovetail slide but the ball mount dooby supplied with the
"wiggler" outfits ought to work just as well. If you also have a
milling machine those wiggler outfits are well worth the cost, I
consider the barrel ended "flick sideways" edge finders beat the
pants off the conventional type. Clive (24649) |
