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.

Like the Sherline 3-jaw chucks, the 4-jaw chucks can be used to clamp either externally or internally. Although we recommend the 3-jaw chuck for standard lathe projects, the 4-jaw chuck is considered the accessory that could add the most versatility to your machine. If you feel the 4-jaw chuck would be more useful, and you have no need for the 3-jaw chuck, any lathe "A" package can be ordered with the 4-jaw chuck substituted for the 3-jaw upon request. A clamping groove allows the chuck to hold parts for milling.