Piper 2 Dual Z Stepper Conversion Mod

This is a modification for the Z axis of the Piper 2. It retains the four lead screws (they are necessary for the gantry's overall stability) but forgoes two of the steppers, plus their associated hardware (Drivers, Couplers, etc). The two steppers can be easily driven in parallel by a single driver, eliminating the need for a CNC shield, reducing the overall complexity of the build. It also makes the gantry more stable, as each side is tethered and is more difficult to slide/skip when the motors are powered off.

It makes use of two GT2 6mm closed loop belts (I suggest 852mm belts, they should fit everything, unless if you are building a really small version). The belt forms a triangle, with the stepper mounted at the front or rear. The side triangles brace two lead screws each.

Note that this design will steal a few mm of Z travel and force you to use longer spacers for your print surface.

If you are asking yourselves "why not use a third belt, tether everything together and