8-Hole Thrust Bearing Race for 8mm or 5/16" axles

This is a bearing race for a thrust bearing. It just needs two M8 washers and 8 x 4.5mm (0.177") ball bearings of the kind normally fired from BB guns. It was designed for the bearings of the RepRap Darwin Z axis, but is a generally useful little widget. Including washers, it occupies approximately the same space as a 608 bearing.

A set of 4 of these bearings has been in constant use for 1 1/2 years with no issues.

Instructions

I print these on a 1-layer raft, then just clear the holes with a 5mm and then 8mm drill held in the hand.

Fit a washer onto the M8 axle, and put the race on top. Load one BB into each hole and sandwich with another washer.

Thick grease or vaseline stops premature discharge of the BBs. They can be printed in most plastics including PLA, ABS and CAPA.