Strange Threaded Lathe Spindle Size?

Hello All,
I have been downsizing my shop lately, sold my old decrepit Sheldon
12" lathe because it's too long, and have been on the lookout for a
much smaller lathe.
I visited a local shop that folded to look at a SB 9" he had for sale.
The SB was really worn, but sitting next to it was a 1980 Winchester
10 x 22 made by Shen Wai in Taiwan. It is in really nice shape. It
had some upgrades; a newer 1 hp Dayton motor. It had a Cushman 6"
2-jaw chuck with special jaws on it; almost totally useless for my
needs. So I said to myself; no biggie, if it's a Cushman chuck, it
must have a somewhat standard spindle mount on it right?
Wrong, after I bought it & got it home. Removed the chuck and
measured the spindle threads. It appears to have a 2" 8tpi spindle.
The unthreaded portion measures 2.00 diameter, the threaded portion
outside diameter is 1.950 or so. It has a 1" hole through the
spindle, tapering up to 1.200 or so. (a #4MT?)
I have never seen or heard of a 2"x 8 tpi spindle. It seems I have
two options; turn the spindle down to 1 3/4" x 8 to fit the newer
Chinese backing plates & chucks, or special turn a rough backing plate
to fit my threads. (which will be hard because I will have to do it on
this lathe!) Anyone with suggestions? Oh, and I cannot find backing
plate blanks anywhere, looked online at WTT, Enco, MSC, etc. Any
suggestions?
THanks, Jeff
Reply to
Jeff W
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I have a Taiwan Enco 10x36 with a 2x8tpi spindle. I could not find a source of metal lathe backplates. There are some wood lathe backplates for that size spindle but they looked a little too flimsy for me.
I ended up making a plain faceplate and an adapter for a 5c collet chuck from a round of cast iron from Mcmaster-Carr. Of course, I had a 4-jaw chuck to start with so the job was doable on the target lathe.
If you're within driving distance of me (Davis, Ca), you can borrow my 4-jaw chuck to make your backing plate.
Reply to
Jim Stewart
I've got a stray 10" face plate with a 2.25 x 8 thread. Wonder what that came from? Useful for your project?
RWL
Reply to
GeoLane at PTD dot NET
I took a closer look at the Cushman chuck that came with the lathe. I didn't even measure it until now. It's a 4 1/2" diameter 2-jaw. Since I didn't look at it carefully, I didn't even notice that it is actually fitted on a small backplate. (The backplate is 4 1/4" diameter, fitted inside the outer edge of the chuck, so it looked integral to the chuck at first glance.) I easily separated the two, and hooray, I now have a backing plate. (albeit only 4 1/4" diameter...)
Here's my new plan. I will buy a 4" 3-jaw self-centering chuck, plain-back, with reversable jaws, and mount the backing plate I have to this chuck. Most the stuff I turn these days fits a self-centering 3-jaw... Then I will get a 6" rough unthreaded back plate and turn it to size on the 4" chuck. Then I'll pick up a 6" 4-jaw independent chuck to fit the new backing plate. (I never have need anymore to turn stuff with larger than a 6" chuck these days....)
I still need to find a source for cheap rough backing plate blanks...so if anyone has a source, please advise....
BTW, thanks for the offer to borrow your 4-jaw, but I'm clear across the country, in Indianapolis.
Jeff
Reply to
Jeff W
While 2 1/4 x 8tpi is not common, while I was searching for 2 x 8, I came across numerous cases of 2 1/4 x 8......however I don't recall what they were. (seem to think it one was 11 inch Sheldon?)
Thanks for the offer, but 2 1/4 won't do me any good. If it were 1 3/4, I could bore it out & thread it to fit, but it would be a bear to do it concentrically....(I'm sure I would mess it up!)
Jeff
Reply to
Jeff W
2.25X8 fits a wide range of smaller lathes - for example it fits my Logan/Powermatic, a 12 inch X 48 inch lathe. in fact, if you want to dispose of it, we could engage in suitable negotiations
Reply to
Bill Noble
Well ... my 12x24" Clausing started life at 2-1/4"x8.
I'm sorry to say that I found a faceplate at 2"x8 and bored it out and re-threaded to fit my lathe. Unfortunately, now that the spindle has been repaced with a L-00 spindle, I can't reverse the process to give you back a 2"x8 faceplate.
Good Luck, DoN.
Reply to
DoN. Nichols
[ ... ]
I hope that you mean reversible top jaws on two-piece jaws.
Note that many 4-jaw chucks don't need a full diameter backing plate. The screws which attach the backing plate to the body usually pass through from the front on a circle not too much larger than the center hole.
So -- get the 4-jaw chuck first, and then see how big a backing plate you need for it.
It is typically the 3-jaw chucks which need a backplate the same diameter as the chuck body or near to it.
Good Luck, DoN.
Reply to
DoN. Nichols
Sounds like Hardinge thread. Ill have to check
Gunner
Reply to
Gunner
I got your email, but your address is munged. I'm interested in parting with it and have some photos. Email me directly and I can send them to you.
RWL
Reply to
GeoLane at PTD dot NET
Getting to be a swap meet here. I have a 12x24 Clausing with a 1.5 x 8 spindle. Do you still have the 2.25 x 8 spindle? If so, it would disappoint Bill since then I wouldn't have a face plate to sell. On the other hand, I'd suddenly have a 1.5 x 8 face plate that somebody else could use.
RWL
Reply to
GeoLane at PTD dot NET
Hardinge is even stranger, 2 and a few sixteenths x 10TPI, IIRC.
Reply to
Ned Simmons
Wholesale Tool on the South side of Indy carries blank rough cast backing plates of various sizes in stock.
Steve
Reply to
StevenJ.Elliott
One of my elderlies is 2" X 8 - IIRC the other is 3-1/2 X 6 - but those are both 1880's vintage...
Reply to
Ecnerwal
[ ... ]
I do.
Are you sure that it would fit? this one is designed to clear 1-3/8" spindle bore (so you can use a drawbar for 5C collets), and I think that your machine has a much smaller spindle diameter and thus smaller bearings.
If you think that it might fit, I could measure over the bearings areas -- and the diameter for the cone bearing for the belt pulley (three belts in parallel going between it and the jack shaft.)
I even have some chucks which still fit that spindle nose, and the modified faceplate.
Enjoy, DoN.
Reply to
DoN. Nichols
Doh! You're right. It's not like swapping the spindle on some drill presses or a Bridgeport to change the taper. I wasn't thinking. The bearings would have to be a different size.
I have a series 4800 (Model 4818) and you probably have a 5300. I don't think they're interchangeable. Was the difference between the 5300 and 6300 the difference between a 2.25x8 spindle and an L-00 spindle and that's how you were able to just put a different spindle in?
Looks like the face plate is still available for Bill.
RWL
Reply to
GeoLane at PTD dot NET
[ ... ]
And the bearing mounts in the headstock casting as well.
5400 (5418 to be specific).
The difference between my 5418 and a 5900 series, IIRC -- but I never knew what machine the other headstock came from. It had the right spacings for the bed ways, which is good, because I had to use the headstock as well -- and some (but not all) other parts which came with it. The L-00 spindle would fit in the headstock, but the lock-down ring for the L-00 taper was rubbing on the front of the headstock. I keep planning to set up the boring/facing head on the mill and making a recessed area so I can go back to the proper headstock casting, so the taper pin will match for locking it in place.
I'm afraid so. I've answered your e-mail with dimensions (diameters) along the length of it so you can be sure. But I think that even the tailstock is beefier on my machine. I have a tailstock which I used for a while which fit the ways and had the right center height, but only had a MT-2 taper in the ram, while the proper one has the MT-3, and I got that later from another e-Bay auction.
The diameter measurements were made with a Mitutoyo digital caliper. For greater precision, I can re-do it with tenth's reading micrometers, but not right now -- and probably not for a few days, as it is getting colder, so heat transfer from my hands to the micrometers frames would introduce errors when reading to tenths.
Good Luck, DoN.
Reply to
DoN. Nichols
I've sent you an email at what I imagine your proper address is, ending in net - in case it doesn't make it to you, my email is prominently displayed on my web site,
formatting link
- I don't use a real email address here for the same reason most others don't - it creates a tsunami of spam as the spiders harvest it.
thanks for following up
Reply to
Bill Noble

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