| Silent chain drive (Jul
18, 2002) |
Underdrive conversion
(Nov 25, 2003) |
| UDF drive conversion
(Jan 29, 2003) |
Under drive SB lathe bed
(Dec 15, 2003) |
| SB 9/10K drive unit shaft
allowance (Mar 8, 2003) |
Underdrive countershaft questions
(Jan 10, 2004) |
| 9" horizontal drive (Nov
19, 2003) |
|
| |
| Silent chain drive |
| I have a 1928
9" junior with a silent chain drive. Does anyone have pictures or
info on these drive units. I would like to know what kind of on/off
switch they had and how and where it was mounted. Scott (5172) |
| Look on
www.lathes.co.uk Tony
Griffith's site there are pics of one of those machines. RC (5173) |
| I'm just
curious, how many members have this setup on their lathe. I really
don't see it that often, does anyone have an opinion as to why, was it
too expensive because I really like mine and I think it is a great
space saver. Would anyone have any old books with a price for this
setup. Scott. (8544) |
| I have a silent chain drive on my Van
Norman mill. After breaking the large drive wheel in a moving
accident, I discovered that neither the drive chain nor the wheels
can be affordably replaced on standard home shop machines. I think
the outfit that owns the Van Norman name wanted $900 for the wheel
alone. So, don't damage yours! Fortunately, I found a used
replacement. Kim (8565) |
| How close to that
silent chain, is the silent chain used as a timing chain on small
block Chevy's? Or the cam-drive chain on a new Twin Cam Harley? My
point being, the specific wheel/sprocket/whatchacallit may be nigh
impossible to find. But if that particular sort of chain is an
industry standard silent chain type and size, would a modifiable
sprocket be more readily available? (8590) |
| A "silent chain" is
somewhat like a bicycle chain but with multiple links across the
width. They come in at least two pitches and multiple widths, and
both the chains and the wheels are expensive. On my mill, I
considered replacing the whole system with a timing belt and
pulleys, but even that option was more money than I wanted to spend
and, in the end, I got what I needed for almost nothing. Kim (8596) |
| Well, for whatever
it's worth, roller-chain components are dirt-cheap by
comparison. (8597) |
| UDF drive
conversion |
| As posted earlier,
the cost of converting to an underneath drive would be very
involved. The bed is different and so is the headstock. Also needed
would be the UND tension mechanism. You might be able to mill your
present bed and headstock, but it would be involved at best. Yes
you would save some floor space. Another solution might be an Over
head drive. South Bend did this with some of the older lathes. The
space savings would be the same. The main contention would be that
the belt would be right in front of you. With some type of guard,
this wouldn't be to bad. Its a thought. Tom (8981) |
| On that note, here are some
pics of a lathe stand we built that moves the drive to overhead. *pictures no longer available* I was
originally thinking that I'd want to fabricate a guard for the
pulley / drive but after building the stand and using it a fair
amount, I didn't think it was required. Your head is well away from
that stuff when in use. Its also nice to be able to just reach up
and grab the big motor drive pulley to spin the lath by hand. I'm
pretty happy with that setup over all. You do have to watch that you
don't over-oil the drive pulley shaft as extra oil will drip down
onto the lathe headstock, but that doesn't seem to happen enough to
be a real problem. Mark (8986) |
| SB 9/10K drive
unit shaft allowance |
| Bert's posting
(copied below) brings to mind a few questions about 9/10K drive
units. I was wondering if others have had trouble with oil leakage
or slinging from the drive unit shafts. I guess those of you with
UMD lathes needn't worry about it as much until you have oil-soaked
belts or a shaft problem like Bert's. Does anyone else have a shaft
running in the iron casting or am I the only one with the older
type? If you have one of these, how much wear does it show (what is
the diametral clearance) now that it's 50+ yrs. old? For a 7/8"
shaft, a Class RC4 fit is (.0008" - .0028") and Class RC5 is (.0016"
- .0036") allowance. Does anyone know the factory spec.? For those
of you with Oilite bronze bushings, is the shaft size 7/8" or 3/4"?
Does the iron casting have a longitudinal slot and wick? ...or just
an oiler? Are bronze thrust washers used also? (9675) |
| John, I got
mail also from you with a lot questions not easy to answer all off
them 1 rpm off the motor is 1450 (50hz frekw here) 2 Sheave on the
motor dual dia. outside is 3" and 4" 4 The big one on the the drive
shaft 10" 5 jack shaft (65 years old now) Diam aprox 7/8 (22,2mm) 6
The bronze bushes are original. 7 the bushes I reamed are not I line
anymore . I have to make the inside dia. in the bushes little bigger
to get the shaft through the two bushes. 8 the 10" sheave is now
attached with a bold and self locking nut 9 the end off the new shaft
(0,905" = 23 mm) has the same diam as the old one so the 10" sheave
fits well ,the dia. off the sheave in the middle for the belt I
reamed it also to 0,905" I hope I give all the answers you asked me
there are oil wicks in mine it looks off some one did this with a
screwdriver or so and a hammer. I think it is no original. Bert (9680) |
| I have one
of the older countershaft assemblies, and when I got it there was
about .020 play, and it made a lot of noise. The shaft was very
badly scored, and there was some scoring in the bore. I first
thought of boring it out and turning an undersized shaft (shaft =
3/4, bore = 1") and using standard oilite bushings. However, I just
made a new 7/8" shaft and did some light reaming in the bore as
there was still plenty of "flat" surface left. There are no wicks in
this setup, and there are oil cups on the top of each bore. Oil
drips out still, but it is not thrown anywhere. It runs quietly. I
am reasonably certain that the reason for the previous scoring was
lack of oil, leading to overheating, scoring and wear. I have
considered putting in grease zerks and using, perhaps, a lithium
grease, but haven't talked to anyone about this. Anyone have any
thoughts about oil vs. grease for this application? Bob
(9681) |
| 9" horizontal
drive |
| I bought a 9" Model
C South Bend that is missing the horizontal drive assembly. After
watching two horizontal drives go on Ebay for more than I wanted to
pay I decided to try and make one. I will use the plans that are
published on the "links" portion of this forum. However, these plans
don't include making the three step flat pulley. Are these pulleys
crowned? I haven't taken delivery of this lathe as yet or else I
would measure the pulley on the headstock.
(15078) |
| Machinist Handbook
(any edition ) has the correct sizes and shapes for flat belt
pulleys which actually do have a crown in them. Ron (15079) |
| Flat belt pulleys
are crowned 1/8" per ft of pulley width. The min to max diameter for
a 1.25" sheave is approximately .025". Said differently the center
diameter of the pulley is .025 larger than the edge. This keeps the
belt centered on the pulley while running, just the opposite of what
you might expect. If you are planning to make the sheaves, one thing
to consider is that hardwood works very well as long as it is not
subject to moisture. White oak or Beech are very tough, Red oak
splits easily. JP
(15085) |
| The pulley on my
drive unit is not crowned, the machine is a 1942 vintage model B
workshop lathe. The pulley on the headstock is crowned. I have built
drive units for two other lathes. In both cases I did not crown the
aluminum pulleys that I made for them. Both drive units work
well. Those lathes also have crowned headstock pulleys. One is a Pratt
Whitney and the other is of unknown origin. I used 6061 aluminum and
just bolted it to a faceplate to turn the diameters and bore the
hole. You can even make these pulleys out of wood if need be. If you
cant get hardwood, just glue up some plywood discs. My sinuses cant
take wood dust so I prefer aluminum. Rob (15086) |
| Ole, I have an
extra three step cone pulley off of an underneath drive unit. If you
want it for $25.00 plus shipping, send me an e-mail. Glen
(15089) |
| I found the section
on flat pulleys in my 11th edition of Machinery's Handbook. Thanks
to all of you who replied to my query. I am at this point,
considering fabricating the pulley out of maple with a steel hub. I
haven't worked out the actual machining process yet. ole
(15105) |
| Underdrive
conversion |
| Does
anyone know how complicated it is to convert a 9" model A to an underdrive arrangement? I assume this requires a different
countershaft, but are there any differences in the headstock of an
underdrive lathe vs. standard behind-the-headstock drive machines.
Has anyone on the group performed this conversion? I'm interested in
doing this since I have a small shop---it looks like an underdrive
arrangement has a smaller footprint. (Also looks neater to my eye)
Caywood
(15193) |
| Caywood, The
headstock is different and so is the bed. You can use an underneath
drive bed for a horizontal lathe, but you would have to do some
amount of cutting to a horizontal lathe bed and the headstock to
convert to a UND. You might think about an over head drive. I think
one of the members has done this. I think he had photos on his
website. I can't remember if I bought a UND headstock or not. Yeah,
I'm like the rest of you, I'll stock pile a bunch of parts and
someday make a lathe out of it. I do have a UDN Korean SB lathe bed.
They are a bit different than the standard lathe beds. So, there
would be a bunch of work to do, if possible and it would be best to
do the Overhead conversion or buy a UND lathe. Tom (15195) |
| Tom, Thanks a lot
for the info. You just saved me some bucks do some convert to
members remember if I stock a UDN lathe beds.
(15197) |
| I welded up an
overdrive setup for my SB 11" lathe. It is modeled somewhat after
the factory setup, but I never saw a factory setup in person so just
looked at some pictures. I could take some pictures of it and write
up what I did if anyone is interested. one note, I just finished
this project a week or two ago and don't have a leather drive belt
at present. Hence, I have not actually powered it up in this
configuration. if you have a week or two to wait and see if it
works, I should have a belt by then. andy b. (15220) |
| Under drive SB
lathe bed |
| Does anyone know
if the 9" SB bed with under drive be converted OK to the
back/overhead type drive? Clint (15638) |
| Aren't the
headstocks different? why would you want to convert to horizontal
drive? i could see the nostalgia value or if you had enough bits and
pieces lying about. IMHO underdrive is the way to go. Less shop
space, fewer moving parts to get caught on, cleaner maintenance. dennis (15646) |
| Hi Dennis, I was
wondering the same thing as Clint was, if the UD bed could be used
for a Horz Model. The reason being if you run across a really nice
underdrive bed with good ways, could it be used to replace a badly
worn Horz drive bed. There is currently a bed on Ebay from an Ud.9"
that is suppose to be in really good condition. If it can be used on
a Horz drive machine it could really help somebody out. BK (15647) |
| I suspect the only
difference in the beds is the notching on the inside between the
ways for belt clearance on the underdrive. The ways are the same
since the carriages and tailstocks interchange, and of course the
rear-drive headstock is already clearanced for the rear-drive belt.
My lathe is a true "frankenlathe"--a late 48" 10K bed under the
headstock/carriage from a 1937-vintage 9C, with "A" apron and
leadscrew from PKE and the "A" gearbox from eBay. Lurch (15650) |
| Clint, I have done
this to some extent. I am not finished with the project. More
painting and cleaning. The headstock etc. do fit. The only problem
might be if you get a Korean made bed. The bolt pattern for the feet
are different. And for those who ask why, this bed was available and
described by Plaza as new as can be. It is. I do have some
horizontal drive beds though. So I might use one of them as I think
they are in acceptable condition. Tom (15652) |
| Underdrive
countershaft questions |
| I am rebuilding a 9
inch underdrive lathe. When I took the countershaft assembly apart
the oil reservoir hade wool packed in where I expected to find felts
similar to the headstock. Has anyone else seen something like this?
Should there be felt oilers in there? The parts sheet that I have
shows oilite bushings but all that I have seen have just bored cast
iron housings. Does anyone have an older parts sheet that shows the
oilers or even the wool? I have found the same type of wool on top
of the felt oilers in one headstock that I took apart and am a
little mystified by that also. (16425) |
| Steve, When you
say "wool" do you really mean wool? Most "felt" from days of yore
was just finely woven wool fibers. If so, I would not consider
finding "wool" in those areas so unusual. Perhaps a previous owner
just wanted to be sure that the reservoir was feeding oil to the
bearings? Bob (16438) |
| Definitely not felt
just a wad of long wool fibers. The headstock had it on top of the
capillary oilers. I am going to give LeBlond a call and see what
they know about the parts that should be in there.
(16441) |
| SAE F1 or F3 wool
felt is used for oil wicking. In some areas felt is pulled apart
some and a piece of hard felt is placed on top. This simulates a
spring mounted felt like is in some headstocks. It also helps oiling
when the oil is very low. You may have just the lower part of the
wick, the hard felt is needed against the shaft. JP (16443) |
