Originally Posted by
TimJ
I always thought the point of chasing the threads was to remove all the paint. Or is it just mostly to get the threads and bb straightened up to proper depth, etc.?
Chasing is done to get the threads clean, smooth and at the proper depth. Facing is done to be sure the opposite bottom bracket (or head tube) faces are flat and parallel. If all that's required is scraping off excess paint, that's fine but often some metal has to be removed too.