I have a 4-jaw scrolling lathe chuck. Each jaw is independantly adjustable
just like a normal 4J but there is also a scroll so once you get it dialed
in you can back it out and go back in. Mine is made by Rohm or someone and
cost nearly $1400 new which is a lot for a 6" chuck. No way is this one
made for wood. I think you can still see these in the MSC catalog. Wear
diapers -- the prices are *astronomical*. I got mine on ebay before it got
"discovered" and the prices skyrocketed.

GWE