4-Jaw Independent Chuck

[92degrees]

I switched my MM 7x16" over to the LMS 4-Jaw independent chuck as I'm doing work that requires multiple holds and I need to have the work concentric each step. I have an understanding of how to adjust the chuck -- my question is that the chuck causes severe vibration on the lathe --- whole workbench shakes even when the work is in a proper hold. I have tried remounting the chuck 3x in each position on the lathe. What else can I try? Thanks.

 

[JimDawson]

Assuming the mass of the work is concentric with the center line, then about the only thing left is an out of balance chuck body casting. I would mount up a nice round stock through the chuck and dial it in. Then take the chuck off of the lathe and support it by the round stock on some level parallels, let it roll to the heavy side, the with a die grinder start taking off metal in non-critical areas in the back. Grind, check, rinse/repeat.

 

[92degrees]

I'm getting vibration with a plain piece of rod stock held concentrically in the chuck...if the casting of the body of the chuck is out of balance...that would seem like a return to me.

 

[JimDawson]

I would agree about the warranty if that's a possibility, and if you want to wait for the replacement. Failing that, the only way to fix it is to balance it. A auto machine shop that does engine balancing would be another option.