Unusual Small Collets

I've previously posted some of the things that we've seen at the Tool Thrift Shop where I volunteer. We have a couple of things that were donated that I need help with.

The first are these small collets. We have most of a quart jar of them. I apologize for the poor quality of the cellphone picture in advance.



The overall length is about 1 1/4" and they have "DALE" stamped on them. The thread major diameter measures .2575" (6.5mm?) and is 40 TPI. The bore is .196", and the key slot is .0675" wide. The diameter of the collett at the key slot is .2998".

Looking for help in identifying these colletts.

We also received a lot of parts that seem to fit a 1 1/4-10 threaded spindle (3-jaw chucks, drill chucks, internal expanding arbors, and other odd things).

There are several sets of these parts:



The od of the parts is about 1.75, and BOTH are threaded 1 1/4-10 on the interior. Something thin could be secured between them and reversed on the spindle if desired. The thread on the joining screw is quite fine, but I did not measure it. Guessing near 40tpi.

Does anyone have any idea for their use, or the lathe that might use that spindle thread?

Dale was a partner of the Hardinge Brothers around 1900. They made collets for all makes of watchmaker lathes in the early 20th century and marked them, "DALE."

The nose shape and abbreviated cone of your collet is strange-looking, maybe modified from the original shape, The body and thread might be right for a Rivett No. 1, which never made the best seller lathe list. Those collets are rare, as are people who want them. I have one of the lathes, but would only want collets in really nice condition.

Here is an early Hardinge collet list.

Larry