Yeah that does make sense. With this spindle completed hopefully I’ll be able to make myself a “final” spindle incorporating some more sophisticated designs.

I had thought that angular contact bearings could be used without preload, although to be fair I’ve done pretty minimal research on them, mostly just enough to learn that they probably would be too expensive to be my first spindle attempt haha.

Actually on that note, how are back to back bearings generally preloaded for a lathe? Ive seen some general examples but not a great idea of how this is done for machine tools.

I actually just watched some of Dan Gelbarts videos recently, that’s really amazing. I thought air bearings required tolerances in the range of ~.0001-.0002 so well out of my abilities, but what an incredible machine