There was a thread recently about cheap drill chucks. I commented that I had a cheap Jacobs with bad runout. That got me to thinking that I could fix the runout. Here's what I did:
- chucked up a piece of steel and turned it to 7/16+- (an arbor)
- fastened the drill chuck on this arbor by tightening its jaws on it
- faced the (mounting) end of the chuck and bored it .600+-, about 3/8 deep
- chucked up another piece of steel & (right to left): - turned 1/2-13 threads for about 1/2" (the drill chuck mounting threads) - turned to .600 for almost 3/8" (a register diameter) - faced a shoulder (register face)
- mounted the drill chuck on this new arbor
- chucked a short piece of drill rod in the drill chuck
The runout on the piece of drill rod was .025 - .030 ('don't remember exactly)!! WHAT?? How could that be? Why wouldn't it be dead on?
This is how some lathe chucks are mounted (with a register diameter and face).
What am I missing?
Thanks, Bob