He's added a fourth axis

[Tom]

I CLAIM MY PINT!

Jeff, the pint's yours! You may have to remind me, but don't be shy!

Ref the angular contact bearings, I'm not really sure. I think the way the big boys do it is to pair a set of single row angular contact bearings opposite each other, and preload them, either next to each other at the chuck end (as a matched pair, with a simple roller at the other end of the shaft), or preloaded along the whole length of the shaft (a non-matched pair, one at each end). I reserve the right to be proven wrong.

As george says, the mini-lathes ship with deep-groove bearings, and the upgrade is to replace them with taper roller bearings. This mod works quite nicely (I've done it), but I don't think you'll see taper rollers in this application on much bigger equipment. I think the mini-lathes get away with it because the loads are low. Which is lucky because the larger angular contact bearings, especially in matched pairs are not cheap.