This mechanical chuck is a bit clunky. The materials, quantity and quality of machine work in this chuck yet produced at such a low cost and delivered to your front door, amazing. These economy tools often need some special TLC first for assembly. More for you buck. Take it apart and smooth deburr the sharp edges you will find most everywhere. A little lube on any bearing pin, Its a great 8 inch Chuck for the price. I installed an D4 adaptor plate on mine to mount on my 14 inch Lathe, This chuck may be too big for smaller lathes. Runs true enough, holds a 2 1/2 inch diameter material into the chuck hole. Machine handles it. Its a great chuck for the price, not my choice for production in a machine shop, but good enough for a home hobbyist. Soft jaws and everything runs perfect..