Small metric collets for sale, 83 pieces. $400

Hey folks.

I've had this box of collets for years, hoping to do something with them, but never got around to it. The one larger collet in the group and the spindle nose and the drawbar fit my 1936 South Bend model C, all of which I am keeping. Ideally, what I am looking for is someone with a comparable set for the SB who would be willing to swap for this set. There are 83 collets total. After carefully measuring them I have come to the conclusion that their threads are metric (but they are marked in fractions and drill sizes) (edited: just realized that some may be marked metric) 15mm x 1.25. They actually measure .585". The SB one is 9/16 - 26. If it comes down to selling them out right shipping will be free in the US, little more outside. Thanks for looking!

Mark

I can't see the collet threads clearly on your photos. Take a look at the thread on your collets that have the M15 x 1.25 thread and compare them to the photo on my ad:

Schaublin Swiss Items W20, W25 Aciera, Habegger

If your collets have the same buttress thread, then they are W15 collets, a rare in-between size that is larger than the W12 used on the Schaublin 70 lathes and Aciera F1, and smaller than the W20 and W25 used on the Schaublin 102 lathes and larger Aciera mills.

If you measure carefully you may find that the thread is actually 14.75mm major diameter, and the collet body is almost exactly 15mm.

Thank you for the heads up!

As you can probably tell, I am unfamiliar with metric collets. I will take a closer look tonight. I had a close up picture of the threads, but could only upload 5 pics to the post and I was in a hurry, so the wrong one got uploaded. Your ad looks great. I hope you can make some deals. Thanks again!

Mark

Chevy427z said:

Thank you for the heads up!

As you can probably tell, I am unfamiliar with metric collets...

Mark

Click to expand...

W15 collets are rather rare in the U.S. If it turns out that's what you have, be patient in selling them. The 45/5º buttress thread is a giveaway that it's a Schaublin collet or one made to fit a Schaublin or other Swiss lathe.

cinematechnic said:

W15 collets are rather rare in the U.S. If it turns out that's what you have, be patient in selling them. The 45/5º buttress thread is a giveaway that it's a Schaublin collet or one made to fit a Schaublin or other Swiss lathe.

Click to expand...

Actually, buttress threads on collets were used on some American Watch Tool Co., Waltham, Mass. lathes in the late 19th century. And the American watch industry back then did use metric dimensions, sometimes mixed with inch dimensions. I have read that the Swiss (Schaublin) adopted some AWT collet designs for their lathes, with thread changes. For instance, the AWT/Derbyshire Magnus-Elect model collet has a 10 mm body with M10 x 1.00 mm buttress thread. The Schaublin W10 collet is identical except the thread pitch is .75 mm.

Anyway, a 15 mm (.590 inch) body diameter and a .587 by 20 TPI (1.27 mm) 45/90 degree buttress thread and an overall length of 2.187 inch means it is the Model 1898 Whitcomb No. 3 collet. AWT stamped the name "Whitcomb" on the body of their collets.

In 1918, AWT was liquidated. F. Derbyshire bought the rights to the small watchmaker lathes, the Webster-Whitcomb, Magnus and Elect. W Wade bought the rights to the larger bench lathes. The Whitcomb No. 3 lathe became the Wade No. 3 lathe. Probably the later collets have the name Wade stamped on them. Tony's Wade page. Wade Precision lathes

Here is a link to an old Wade catalog which shows the No. 3 lathe and attachments. http://vintagemachinery.org/pubs/2132/18003.pdf
Tony has a couple pictures of the No. 3 lathe in his Derbyshire section. Derbyshire & Webster Whitcombe Watcmakers' Lathes

Here is a page of collet dimensions from an early Hardinge catalog that shows the various AWT (Whitcomb) collets.


I suppose it is helpful to know those collets fit AWT/Whitcomb 1898/Wade No. 3 lathes, but the bad news is that those lathes are very rare. The good news is that a lathe owner would be glad to buy them.

Larry

L Vanice said:

Actually, buttress threads on collets were used on some American Watch Tool Co., Waltham, Mass. lathes in the late 19th century...
Larry

Click to expand...

Wow, I had never heard of American collets with buttress threads. As to the mixed in/mm dimensions, perhaps that might explain why the Schaublin W25 collet has a 15 TPI thread, all other dimensions being metric.

It is possible that W15 is a "Schaublinization" of an American collet, like they call the 5C the W31.75.

If that word catches on I want credit"

Thank you for that additional info Larry! Very informative!

I just remeasured them and the threads are definitely buttress. The major diam measures 14.85 to 14.87 and the bodies measure 14.98. The pitch is definitely 1.25. I didn't see Larry's post about markings on them until I got back down to the house, so I will double check that tomorrow. I am cutting and pasting both of your descriptions to a word document so I can better explain to anyone asking in the future.

I appreciate your time gents!

Mark

Edited: MY first time ever seeing buttress threads on a collet. I lost the damn thumb nut on my pitch gage as it spun off across the floor! Guess I know what I'm doing tomorrow. LOL

Chevy427z said:

Thank you for that additional info Larry! Very informative!

I just remeasured them and the threads are definitely buttress. The major diam measures 14.85 to 14.87 and the bodies measure 14.98. The pitch is definitely 1.25. I didn't see Larry's post about markings on them until I got back down to the house, so I will double check that tomorrow. I am cutting and pasting both of your descriptions to a word document so I can better explain to anyone asking in the future.

I appreciate your time gents!

Mark

Edited: MY first time ever seeing buttress threads on a collet.

Click to expand...

Can you tell the difference between a thread pitch of 20 TPI (1.27 mm) and 1.25 mm (20.32 TPI)? For that matter, could Hardinge tell the difference back in 1909? The AWT 10 mm collets have a 1.00 mm (25.4 TPI) pitch, so I would readily believe the older No. 3 collets also had a metric pitch. The Hardinge chart lists the Webster-Whitcomb collet thread as .270 inch x "63 Metric" (.63 mm or 40 TPI). I wonder about the capability of American lathes in use in that age to cut both metric and inch threads. I expect a 127 tooth gear was used. I do have 127 tooth gears for my Hardinge Cataract and Derbyshire lathes.

Anyway, I don't know if Hardinge made their collet chart by measuring competitors' collets or got actual engineering drawings from their competitors. What do you think?

Larry

According to my Schaublin specs, the major diameter of a W15 thread should be 14.75mm, so those collets have a slightly larger thread.

I suppose your best bet is to find someone with an optical comparator and check them on there. If the thread is exactly 1.25mm pitch and you can see the 45/5º angle of the buttress thread then they may be W15. I haven't seen any other buttress thread specs that are 45/5º