Adding Structure - Printing in Plastic: Build Your Own 3D Printer - page 191

Figure 12-1. The anti-backlash nut screwed on to the lead screw
Next, insert the collar and then a single bearing, as shown in Figure 12-2. Don't tighten the collar
yet, and push the collar and bearing to the mid-point of the lead screw. If you find that the bearings
don't slide easily onto the lead screw, use 600 grit Emery paper and carefully sand about 4” on one end
of the lead screw. This removes the thickness of the paint on the lead screw and the bearing should slip
on with ease.