Alfawise U20 - Z_Axis MGN12H Linear Rail

thingiverse

I'm rewriting the text to make it easy to assemble linear guides MGN12H on the Alfawise U20 3D printer for the Z-axis with minimal effort and maximum results. This project has finally eliminated the layer shift that I was experiencing at a certain height, which may have been imperceptible but was really annoying. To mount the linear guide, you need to invert the X motor on its axis. To do this, I created the first support called "Motor X Support with EndStop" that allows you to mount the motor towards the user and place the endstop above it perfectly touching the original block. IMPORTANT: When inverting the motor, you must invert the cables as well because it cannot be done via software. Look up on YouTube "How to reverse Nema stepper". In any case, just swap the central cables with each other and the external ones with each other. Now that the Z-axis is free from the motor side, you can use the remix I made for the linear guide taken from another project but not corrected for the distance of the holes which did not match this printer as they didn't in my case either. The file is "Motor Side Support". On the opposite side, there's a note because the right side doesn't allow you to place the linear guides (the plate and support holes don't match) and the screws that hold the wheels are shorter than on the right side so you need to replace them or use the special-made support with sockets for the bolts to recover the missing length. The file is "Motor Opposite Side Support". To assemble the right side, I had to: - completely remove the wheel with the eccentric placed internally on the right side and its screw; - buy a pair of M4 screws where one must be flat-headed or at least flattened (the one that fits flush with the frame) up to 10mm long (better 8mm because otherwise it touches the frame); - replace those screws with the ones connecting the metal red plate with the X-axis frame and the Z-axis wheels; - buy T-NUT M4 to place behind the X-axis to connect the plate to these bolts and make the piece slide towards the outside until the plate holes match those of the linear guide support. If you don't want to buy T-Nut, you can use printed parts with bolts. There are various projects on Thingiverse that you can find. Once everything is aligned, just mount the linear guides on the opposite side of the motor and connect them to the X-axis and test the printer right away. Good prints!