My philosophy is different there so we'll just have to agree to differ and leave it at that.

Quote Originally Posted by Tenson View Post
I think I know what the issue is anyway. On the ballnut mount I didn't have those massive retaining nuts on the shaft tightened up very much. That means when it pulls on the shaft the pulley inside the mount rubs. Does that make sense? However if I tighten the nuts on the end of the shaft to keep it in place, the shaft then rubs on the body of the mount since the two bearings are not perfectly parallel. I think I need to put a tiny spacer in there.
I was going to suggest checking that the angular contact bearings are both the right way round, since if one was the wrong way that could cause rubbing and hence a noise in one direction. However what you suggest here sounds much more likely. I recall only leaving a very small shoulder (0.1mm ish) on the shaft so that the portion of the shaft close to the bearing acts as a second seal/shield. If this shoulder is too small then the shaft could rub on the mount if the bearing outer ring is not flush or protruding from the surface of the mount? The mount should only be run with the locknuts correctly tightened, so tight enough to eliminate backlash but not so tight as to damage the bearings. As the shaft is rubbing with it tightened properly I need to either skim about 0.2mm off the place on the shaft to stop it rubbing, or make a spacer as you suggest.

Since I'm currently in Nottingham in the week I could only modify the shaft next weekend, but if you want me to make an accurate washer (25mm ID, 35mm OD and 0.5mm thick should do it) then I can do that now and post it to you on Monday?