DIY Bearing Blocks

Leadscrews and the associated bits all seemed too expensive. Firstly you need the lead screws, then bearings and something to take the strain so that your precious motor bearings don't get ruined. Then come the anti-backlash screws etc etc....

I decided to use some M8 threaded rod instead of leadscrews and found the straightest ones I could in the local DIY shop but now how to mount them????

I had some 8mm bearings lying around (as you do!). Two problems had to be solved.... firstly, the bearings had to be held firmly so they couldn't shift but could rotate freely. Secondly, the M8 rod had to be help such that it could rotate freely but could not move laterally.

I found that the bearings were the same thickness as some plywood I had and made a sandwich with three plywood squares and labelled them '1', '2' and '3'. A simple adjustable hole cutter in a pillar drill cut out the hole for the bearing in piece '2'.

Now for the rod fixture... I found a steel M8 "T-nut" that fitted perfectly through the bearing.

The four folded "spikes" on the T-nut broke off very easily when I tried to fold them backwards. The barrel part of the T-nut was a bit longer than the thickness of the bearing so I filed it down so that it matched nicely. This allowed me to tightly clamp the centre piece of the bearing without crushing it.

The final stage was to recess enough room for the T-nut and on the other side have space for a self locking nut. The recess for the T-nut is a smaller diameter than the hole for the bearing so the outer back of the bearing remains sandwiched in part '2' between parts '1' and '3'.

To my great delight... it works! Cheap, easy and simple to mount to an overall wooden structure.

A simple view of the assembly (please ignore the "ears" still fitted to the T-nut)