Identifying Lathe Collets

could you post a picture of them?

like for example:

http://shopswarf.orconhosting.net.nz/colletap.html
http://www.tools4cheap.net/products.php?cat=8
http://www.grainger.com/Grainger/collets/machine-tool-accessories/machining/ecatalog/N-bvw?op=search&sst=subset

Maybe something like a Unimat lathe collet?

The Morse taper in the inserts come in only 8 different variety, of which I am only familiar with 2 on the chuck side. Please check Wikipedia, and start from there.

Google search for Hardinge Work Holding Tooling. You'll find a virtual cornucopia of various collets and tooling for lathes and mills.

These collets are probably not for lathes. They look like Bridgeport mill collets and their description also fits. They come in sets and are available from machine shop suppliers. Call one of your local machinists and ask where to get them. By the way, lathes have chucks.

From your description these collets may be from a jewlers/watchmackers lathe or a small instrument lathe such as a boley.I have seen more than 4 different collet dimensions used on watchmakers lathes, the Boley size being the most common. Does your lathe have any markings on it that could give us a clue?

Good luck,

Doug

These are R8 collets primarily used on milling machines.

You are absolutely correct. If they were lathe collets they would not be threaded on the pull end. I have used many of them in the machine shop over the years. They are made to hold mills tightly in the milling machine.

R-8 (Bridgeport collets and tool holders) are threaded 1/2-13 and an example of Bridgeport collets are shown in #1. However, these aren't the collets in question. The collets in question have a 5/16-32 thread.

Maybe they are not Bridgeport but they are not meant for lathes.

Here is a link that has a picture of a typical lathe collett.

http://www.roviproducts.com/Hardingecolletpricesheet.htm

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