With a 3.1\" diameter body, this chuck is identical to the Sherline # 1040 self-centering chuck except that it has a 1″-8 TPI thread that accommodates most wood-working lathes. Because this chuck was initially designed for machine-lathe work, its accuracy far exceeds what is necessary for general wood turning. It has a clamping range of 3/32″ (2 mm) up to 1-3/16″ (30 mm) diameter with the jaws in the normal position. With the jaws in the reversed position, work up to 2-1/4″ (56 mm) can be gripped. The hole through the chuck is .687″ (17 mm). Rotating the knurled ring closes all three jaws simultaneously to quickly grip round or hexagonal stock. Tommy bars (provided) are used in the holes in the side to tighten and loosen the chuck for more leverage.

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