Z Axis Guide

I didn't have a lot of luck with the cantilever Z axis on the D-Bot printer. Here is a design that positions the guide wheels between the side supports and has a wider spread on them. The installation only requires that the beam be square to the upright and a slight amount of pressure against the supports by all four wheels.

This setup is rock solid and the stepper motor now mounts in the middle of the support. There is also a spacer included for this setup so that the stepper and lead nut