So I printed out the pieces on a delta 3d printer and a ultimaker original. I have never tested a deltaprinter before so that was fun. It turned out that mostly the design worked as intended. One mistake I made was that the spheres where to small.

I then made the spheres 3mm instead of 1mm. And printed it again on the deltaprinter.

This looks much better. I printed out the rest of the pieces and assembled it with m5 screws and locknuts:

Finally at testfit on the rail it should be mounted on:

Yay! It mounted firm and secure! This looks very promising! I made some minor tweaks and I am going to print out new brackets tomorrow.