Product Code

Product description

Fully machined back plate can be mounted onto 4"3 jaw or 4 jaw self centering and independent lathe chuck (p/n 202-5410, 202-5472,202-5600, 202-5419). As long as back plate Shoulder Diameter 2.87"> chuck's D1, all 4" chuck will fit in. All back plates have 0.04" allowance, please measure the size of Chuck's D1 before process your back plates. The size of back plates's D1 should be a little bit smaller than the size of Chuck's D1. Because the gap between back plate and chuck is smaller, chuck's TIR is better. No gap is the best. D1 need to be processed before back plate can be mounted.

You would not need to drill any mounting holes but you will need to turn the shoulder down .040" to match the back of the lathe chuck to make the chuck & back plate more concentric with the lathe spindle. When turning the shoulder of the backing plate, ONLY TURN THE SHOULDER OF THE BACKING PLATE WHEN ATTACHED TO THE LATHE SPINDLE. If you use a chuck to clamp the backing plate and then turn it, the backing plate will not be true to the lathe spindle and will have more runout than specified when the chuck and back plate are put together. 

• The back plate may come with two or three additional screws (depending on type) for removal the back plate from the chuck. They are not used to mount the chuck to the back plate, mounting screws should be included with the chuck