Machined-in-place collets are nothing new but it gets tricky when the center hole is too small to true up with a boring bar. One solution is to make a "Crush collet". This approach can be used with any hole that can be drilled and, if desired, reamed.

If you are interested, please see

http://rick.sparber.org/CCWW.pdf


Your comments are welcome. All of us are smarter than any one of us.


Thanks,

Rick