The Shopsmith Lathe Screw Center is Ideal for small turning projects. Especially designed for turning small diameter workpieces like knobs and lids from 1-inch to 5-inches long without using a Tailstock Center. Simply drill a pilot hole and thread this center on. Mount the Screw Center with workpiece on the lathe and secure with included set screw. Lathe Screw Center is 1-1/2” diameter and 1-1/2” long with a 5/8” diameter ID.