Quote Originally Posted by m_c View Post
If you need better tolerances, then you either need to use custom bored soft jaws, a collet chuck, or a 4 jaw chuck.
You are right, the pulley play does not matter that much, unless the play is transferred to the chuck.

This is a 4-jaw chuck, it is a self centring type, I don't know if that's good or bad, I think in some situations it is good, in some it is bad.