Quote Originally Posted by Paul Jones View Post
Marv, this is an excellent suggestion for more safely turning an eccentric on a lathe without having to resort to using a shim when a 4-jaw chuck is not available. Thanks, Paul
It's certainly safer than the single jaw shim disaster-waiting-to-happen approach but it depends on having the required diameter stock available (very unlikely) or needing to turn the stuff to size before milling the slot. A lot of time and effort compared to popping it into a 4jaw and centering (see my centering procedure elsewhere).

If you're interested in safety and accuracy buy yourself a 4jaw and learn to use it.