| 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) |
| There's
http://www.sc-c.com/metallathe/index.htm
that has a 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. See
http://machinerepair.com/scraping.html
See also Tony's Scraping Page at
http://www.csgnet.net/toolroom/scrape1.htm
(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. .......
www.Zatcoff.com for the web site.
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. Below is info clipped from
one website http://www.mtsandtg.com/products.htm (I have no
connection with this company) 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
http://members.cox.net/mymhh/Bridgeport%20Oiling.GIF
Note that this is case sensitive. It is also a large drawing to
preserve detail. If you have Opera as your browser, you can just
crank down the zoom value to 20% and see the entire thing. 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 hobby |
