QUBD TwoPointFive-Up

I kickstarted the QUBD OneUp, and my friend, the TwoUp. And of course part of the issues it had was massive Z sag, due to the design of the printer mainly with a heavy X gantry and only one Z stepper/leadscrew.

This is an attempt to donate my OneUp parts to his TwoUp to make a "Two point Five" version. that is exactly the same, with an added Z stepper and leadscrew.

I wanted to make this mostly compatible with stock One/Two-Up printers without moving inside parts around too much. I wanted to be able to have these parts printed from the printers in true RepRap type fashion, to upgrade themselves. Sadly, the OneUp will not be able to print some parts, but the TwoUp should have no problems.

If you wish to make this modification, I would suggest making sure that BOTH the Z stepper motors are the same. It might be easier to get a single stepper, and replace either the X, Y, or E stepper (and adjust voltage for it accordingly!). Then use said removed stepper as the second Z. I do