I have a Jet 1236. Prior to Thansksgiving weekend last year I had no issues with it, turning pens, other kits, handles, and bowls. (Bowls is the real issue here). That weekend I put a very large, heavy piece on that was pretty badly out of balance and apparently damaged the lathe. Unfortunately, a few seconds later, in and un-related incident, I badly sprained my ankle. Anyway, When I was finally able to get back on the lathe I couldn't turn a bowl because of 'spin-out' (out-of-round). I tried and tried assuming that I was the problem. Finally I took it into the shop and they replaced the bearings and the drive shaft. That was a couple of weeks ago that I finally got it back. I turned some smaller projects without incident but this weekend I tried bowls again, and I'm having the same problem - I just can't the a bowl round, no matter how many passes I make, there is still chatter against the surface - worse the farther from center I get. If I run the tailstick up to a spur chuck mounted in the drive and then spin the head by hand I can see a tiny variance in the drive, .25 mm or less, but I saw this before I took it to the shop. Advice? Is it likely that I have re-damaged it? It wasn't fixed properly? Some other problem? Help! I'll take it back to the shop, but would like to go ready for pushback.