This is a way to sync the Z-axis drive using a single motor. Printed parts: - top left plate, the motor and idler are mounted here - top right plate, essentially a mirror image of the left plate, but without the motor and pulley. rod_plug.stl (print 2) - replaces the original guiding rod plugs on top plates rod_holder.stl (print 2) - holds the guiding rods from below, since the moto aren't there anymore tube_guard.stl (optional) - keeps my bowden tube from interfering with the timing belt If you prefer the motor on the right, you can print mirror images of the and . Hardware needed: use the original 4 M3 screws and nuts to mount the top plates 976mm 488 teeth GT2 (6mm) closed belt ( GT2 18 teeth pulley 5mm bore - mounted on the motor ( 2x flange bearings 8mm bore ( 2x GT2 36teeth timing pulleys with 8mm bore ( 1x idler pulley for GT2, 5mm bore - ( M8 rod, length 349mm - needed to stiffen the frame, because the frame is too flimsy to withstand the timing belt teion 4x M8 nuts and washe to fix the M8 rod 4x M5 25mm screws and nuts and washe - to fix the flange bearings 1x M5 40mm screw and 2x M5 nuts and a washer - to mount the pulley idler 2x M3 20mm screws and nuts for the top rod plugs 4x M3 15mm screws and nuts to mount the bottom rod holde 4x M3 12mm screws and washe for motor mounting The mounting holes for the flange bearings are a bit oveized so you can keep the leadscrews and the guiding rods parallel. The way I did it: Mount the flange bearing without tightening the mounting screws fix the leadscrews in the bearings bring the X-axis assembly (the one that rides on the leadscrews and rods) all the way up (maximal expected Z height) eure that the leadscrews are parallel to the guiding rods (I eyeballed it, by keeping the bottom of the leadscrews above the Z motor axes, which were yet unmounted at this stage). tighten the flange bearing mounting screws Don't forget to change the steps/mm parameter for the z axis (from the original 400 to 800) Hope I included everything here. If you find anything missing, please comment and I'll aweupdate.