Description:

These chucks have four advantages over 3-jaw chucks.

1. They can be used to hold irregularly shaped parts.
2. They can be used to center parts with a great deal of accuracy.
3. 4-jaw chucks can be used to deliberately hold a part off-center.
4. They can clamp stock tighter.

This is a valuable asset when machining cams, crankshafts and similar parts. The main disadvantage of the 4-jaw independent chuck is that the jaws must be set individually, adding considerable setup time. The jaws are reversible to accommodate larger stock.