which size is better alround

[deannos]

The bearing nut thingy (picture below so everyone else knows what we're talking about!) should work better on a trapezoidal screw than the M16x2 threaded rod you're currently using. Just need to make sure it's the right size to engage properly. What's the internal diameter and width of the bearing, or just the number on the bearing? Did you add the springs to it as I suggested?[/QUOTE Thanks for the reply Jonathan, I've not used springs and it seems ok, i will check the bearing tomorrow for a number. The pc running everything gave up today so i went and had a few pints instead. Only just realised what you were saying about the price, i.e trap screw against a ball screw