Bezel chuck

Small bezel chucks (usually with internal and external jaws) are familiar to watch and clock makers, but are a useful tool in any shop. Few are commercially available and prices are very high. I converted a 100mm (4") four jaw self centring chuck to a larger bezel chuck. This involved cutting the chuck jaws, machining a step in them, and bolting a blanks to be cut with the steps to be machined in place on the lathe . After machining the steps the segments were separated. Since the steps are machined in place and the whole range of adjustment is +/_ 1.4mm , the chuck is very accurate. Total run-out is less than 0.01mm over the 12 to 101 mm holding range.