Anet A2 dual Z single motor by olev

Last crawled date: 3 years ago

I wanted dual Z screws with single motor, and Supasorn's Tarantula solution was very simple and elegant. I remixed this to fit Anet A2. The difference is that on A2 the distance between vertical frame and X bar is bigger, so motor mount and top mount had to be edited. I moved the position only 1mm further out on both, that is enough. I also edited the switch mount to match the switches used on A2 and moved the switch position on motor mount accordingly. I have added a new holder for X endstop switch, as the original doesn't fit in the correct position any more due to the 2nd leadscrew.
Supasorn's original lead screw nut holders should be used, I have included the files now for convenience, they have not been changed from original.
All parts use M4 screws & T-nuts, except motor mount, which uses M3 screws/nuts. All could easily be edited to use other sizes, but I left them as they were, as I had all sizes available. If you want to use Anet original M5 screws/t-nuts, just print the parts with 100% infill and drill out the mounting holes with 5.0 or better yet, 5.5mm (to give you some alignment room) drill.
Edit: full screw list, as it was requested:
10pcs of 412 CS + 4mm washers (2+2 for each upper mount to frame, 2+2 for nut mounts to X-bar, 2 for X-switch mount)
8pcs of M312 BH + 3mm washers + locknuts for upper bearing mounts (2 per side) and nut to nut holder (2 per side)
6pcs of M38 BH for fixing motor to motor holder (4) and Z switch riser (2)
1pcs 320 screw for Z height setting (I could get away with 10mm, but YMMV here, as I'm running a custom bed mount and glass on top of the bed)
2pcs of M310 (M38 would also do) to fix motor mount to the frame
Original screws for X and Z switch mounts (28 or 210 CS, if lost/stolen/broken)
Original grubscrews for pulleys and upper bearings
It's perfectly usable also as single inverted Z with original leadscrew - just print the motor mount, Z switch mount and right nutholder.
To use this, your Z motor direction has to be reversed from stock! You can do this either by using Marlin firmware and setting #define INVERT_Z_DIR true in "configuration.h" or very simply by switching either black and green OR blue and red wires in the Z stepper cable, this reverses the motor.
I'm very happy with how it works, adding 2 pics of my latest taller prints (~100mm), absolutely no Z issues.
UPDATE: added right top mount that includes mount for A2 stock extruder
NB! Read also the "Post printing" part!