Parametric Linear Bushing with Filament Inserts

A 3d-printable plastic bushing SCAD code based on the rather clever design of delgueda that uses POM, nylon, or other filaments as bearing material inserts.

Upon testing their version, I noticed that with only 4 inserts the bushing could still rock and rub against the rail. I modified the SCAD code to support variable numbers of inserts (5 & 6 seem good), as well as made the spacing adjustable and added end chamfers.

One thing to try is to roughen the insert filament with a file to allow rubbing dry lubricant (graphite/moly) into it for a self-lubricating effect. These bushings are supposed to be quite long lasting and can be made very tight.