Help identifying collets

I have about 30 imperial collets that I thought at first glance were 5c (not at that stage knowing anything about 5c collets!) and now having looked at them more closely I have two different types, neither 5c. I wondered if anyone can identify them from the photos/ (very) appx dimensions? Many have double c logo on them. Other markings are difficult to make out but in addition to sizes I think I could see 664.  Not sure if they are of use to anyone.

Edited By John D on 24/06/2023 22:37:26

Edited By John D on 24/06/2023 22:57:06

John, the CC indicates that those collets were made by Crawford. That doesn't help you much as they were collet manhufacturers (hence CC). The collets look reminiscent of lathe collets used earlier in my life, such as South Bend.

There was some discussion in 2015: Posting No. 112438

From that thread, Michael Gilligan converted some scans, here are some sizes: MG's album of collets

And a list of externally threaded (C-type) collets here: C-type collets

Bill

They may very well be of use once identified!

No they are not ER 'number-C' collets. They look more like ones made for a lathe, rather than milling-machine, collet-chuck.

If your measurements are more accurate than you claim, the distinctly different sizes suggest two sets mixed up! I'll examine my set, which looks of similar size.

There are indeed two sets mixed up. The upper photos appear to show the majority to be V5 collets (Van Norman #5) from the dimensions and the notch in the taper. The lower ones are still a mystery.

Can you measure the head diameter and threads of the lower ones. If they are 35mm head and M22 x 1.5 thread I can maybe use them if there's a usable selection.

The fine thread might be BSB. When I bought a set of Bell Chucks, the collets had BSB threads.

26 tpi Whit Form. Not to confused with BSC which is 60 degree thread form

Howard

Edited By Howard Lewis on 27/06/2023 11:40:59

Been a busy week. I’ll measure the threads and head on the lower shaped ones when I can get down the to the workshop.

I’m now sure the top ones are Van Norman V5. Does anyone this side of the Atlantic use them do you think?