Quote Originally Posted by eskimo View Post
...I was thinking these C2821 | PA-160/D1-4 3 Jaw Adjustable Scroll Chuck Camlock Mount | machineryhouse.com.au might have been the go....but I guess i as worng
If your lathe has camlock mount, you do not really need an adjustable chuck with backplate. Go for a good direct mount chuck (with integral mount, eg no backplate at all) instead. The camlock spindle nose will mount your chuck perfectly repeatably, without need to correct each time you mount the chuck. Adjustable 3-jaw chucks make more sense for lathes with threaded spindle noses, where it may be becessary to manually center the chuck body after each mount. An adjustable 3-jaw chuck is not a substitute for a 4-jaw chuck. Using an adjustable 3-jaw chuck to routinely center the workpiece is in my opinion not a good idea. A quality 3-jaw chuck, if not abused, should let you re-chuck to better than 0.05mm runout without needing to touch any adjustment screw. If you need more accuracy, use either collets or an independant 4-jaw chuck or work between centers. And occasionally it can make sense to clamp a smaller 3-jaw chuck into a larger independant 4-jaw chuck. Chris