05-05-2015, 04:49 PM
I got the chuck apart today but didn't find what I was expecting. No broken or cracked parts that I can see, but I did find evidence of Jacobs moving their production over to China. 
After pressing the sleeve off of the chuck body I found a tiny coiled up steel chip inside about 3/64" across. After cleaning up all the parts and inspecting them, I believe the chip came from one of the teeth on the #3 chuck jaw. I found it wedged between the jaw and it's bore in the chuck body.
I also found a 'peak' on the crest of the threads, on one of the half-nuts that drive the jaws. Almost like a chisel tip on a center drill. It will catch a fingernail running over the peak.
Most notable though are the burrs, chips, and mediocre surface finish inside the bores for the chuck jaws. I just about had to pry the jaws out of the chuck body they hang up so badly. It's going to take some time to de-burr and smooth those surfaces down with a round Arkansas stone.
After pressing the sleeve off of the chuck body I found a tiny coiled up steel chip inside about 3/64" across. After cleaning up all the parts and inspecting them, I believe the chip came from one of the teeth on the #3 chuck jaw. I found it wedged between the jaw and it's bore in the chuck body.
I also found a 'peak' on the crest of the threads, on one of the half-nuts that drive the jaws. Almost like a chisel tip on a center drill. It will catch a fingernail running over the peak.
Most notable though are the burrs, chips, and mediocre surface finish inside the bores for the chuck jaws. I just about had to pry the jaws out of the chuck body they hang up so badly. It's going to take some time to de-burr and smooth those surfaces down with a round Arkansas stone.
Willie