Sherline 3.1 in 4-Jaw Self-Centering Chuck 1076
This chuck combines the ease-of-use advantages of the 3-jaw chuck with some of the advantages of a 4-jaw chuck. It will automatically center square or round stock. (The stock must be accurately shaped for all four jaws to grip.) It will also grip thin-wall tubing in four places rather than three, which spreads out the load and allows more grip without crushing the tubing.
Turning the knurled portion of the outer diameter of the chuck scrolls all four jaws in unison. Included with the chuck are two Tommy bars for tightening and loosening the chuck. The spindle thread is 3/4-16 to fit all Sherline and similar spindles.
Centering accuracy on self-centering chucks is to within a few thousandths of an inch. If perfect centering accuracy is required, see the section on 4-jaw independent jaw chucks.
This chuck will hold parts from 3/32″ in diameter up to 1-1/2″ with jaws in the normal position and up to 2-3/4″ with the jaws reversed. A smaller 2.5″ diameter chuck is also available as P/N 1075
Chuck Diameter: 3.1″
Jaw Capacity With jaws in normal position: 3/32″ (2mm) – 1-1/2″ (38mm)
With jaws in reverse position: 3/32″ (2mm) – 2-3/4″ (70mm)
Through Hole Diameter .687″ (17mm)
Thread Size 3/4-16 (other thread sizes available in 2.5″ diameter)
Chuck Body Material 12L14 Steel
Chuck Jaws Material 12L14 Case Hardened Steel