Turn the body of the bench screw on the lathe. Finish by cutting a groove for the garter in the collar. The garter locks the bench screw and vise together so that the vise and bench screw move together as one unit.

 

A quick note: Visitors will see that the garter groove is being cut in a larger diameter section of the screw's shaft, abutting the screw handle. I have built and installed four tail-vises on different benches. I found that cutting the garter groove directly into the 1-1/2 inch dia. screw shaft weakened the bench screw at this point. I have accidentally twisted the head of a bench screw right off when tightening the vise. A real bummer. As the shaft of the screw has to pass through the rear jaw of the tail-vise before being threaded into the nut cut in the end cap, it seemed reasonable to increase the diameter of the hole cut into the rear jaw and increase the diameter of the screw where the garter groove is cut. For my own convenience I call this a 'collar'.