On Nov 12, 11:03*am, "Pete C." wrote:
...
The Adjust-Tru chucks have provisions to allow them to be adjusted to
run true, but I expect that trueness only applies at the particular part
diameter that they are adjusted for.

A new, unworn Bison Set-Tru does that. I use the 3-jaw for speed and
convenience, the 4-jaw for accuracy, the Set-Tru feature very rarely
for my one-off type of work.

jsw