View Full Version : opening 5C collet...

David Rose
05-28-2007, 04:27 AM
I just got in a cheap spindexer with a precision collet (which will not thread on) and a Chinese "emergency" brass collet. I want to play with this thing. So what is the best way to drill/ream/bore the brass collet?

I was just going to chuck it in the lathe and drill and ream it. Then I realized that the difference in diameter from front to rear of the straight portion is .010". That won't chuck! The collet has a short steel pin in each relief slot. I assume they are there to keep the jaws rigid for machining. Are the these pins tapered? If so, I might be able to pull them a bit to reduce that end. But if they are, and I pull them some, this will effect alignment when they are removed, won't it?

I also thought of just wrapping some shim stock around the small end. But I don't think that would give very precise alignment either. And then there is the misalignment when the pins are pulled. Maybe that is all that can be expected for the precision of the emergency collet?

Btw, I don't need "high precision" for this part, but would like to shoot for reasonable.