I'm a huge fan of belt driven Z-Axis, so much I made one for my own printer (I usually use a modded tevo tarantula).
I love it so much I decided to make one for this wonderful machine!
Sadly, I do not own one, so I have not printed it, but all dimensions are in check and it should print and work without problems!
But why choose belts over leadscrews?
Belts are cheaper than leadscrews, will never have overconstraing problems because they cannot apply lateral forces, this means no possibility of Z wobble.
Also, changing the worm gear will easily allow you to increase the Z resolution.
Another advantage is that you only have a single nema17 motor and no metal-on-metal contacts thanks to the removal of the nuts and leadscrew, this means a quieter printer, as if the mk3 wasn't silent enough!
One last thing: belts have no backlash, and as such, with that mod your machine can even pass the #invertechallenge
You'll need some additional materials, here is the BOM:
- 1x Nema17
- 1x Worm gear (8mm bore for the gear, 5mm bore for the worm)
- 4x Skateboard bearings ( 622RS/622zz or variants: 8mm bore, 22mm diameter, 7mm thickness)
- 2x 40T Pulley for 6mm GT2 belt
- 2x 40T Idler for 6mm GT2 belt
- 1x Steel rod (400mm lenght, 8mm diameter)
- 1x 5 meters GT2 belt (6mm width, FIBERGLASS REINFORCED, IT'S IMPORTANT)
Plus screws and nuts, ranging from M5 to M3
You'll also need to adjust the e-steps of your Z axis using this formula:
- Srev = number of steps per revolution for the motor (usually 200)
- Wmul = the multiplier factor of the worm gear
- Fm = microstepping factor (usually 16)
- p = pitch (2 for a GT2 belt [it means 2mm])
- Nt = number of teeth (40 with our pulley)
In the images you can clearly see where the belts are supposed to be inserted in the X-Axis pieces and folded to lock them in place using a teeth-to-teeth action, they can be blocked using normal zip tie.
I'll publish here the Fusion360 project after the end of the contest