Prusa MK3 / MK3S Y-Axis Linear Rail Guide Upgrade

thingiverse

--- TESTING IN PROGRESS --- Works for me so far, some Ideas still to-do (more support points, some kind of leveling, ...) I want a stiffer and more robust Y-Axis Carriage on my Original Prusa MK3. The Commercial Upgrade I've found had a few disadvantages for me and it's not very cheap. So I've designed my own Version without the disadvantages, make it more robust and cheaper (only a quarter of price if China Rails are used). My Design works with Standard Firmware Calibration method. You don't lose 3mm of Height (3mm higher like the Commercial Version will cause that the firmware calibration process runs into an error). I used the Extrusion to mount the Rails rather than the original mounting holes. That's much more robust in my opinion. In my case, the used Guides and the used Guide Blocks are less noisy than the original Linear rail parts. The Main problem are the Guide profiles. Mostly you get only a length of 350mm but you need 330mm long Guide profiles. It's not as easy to shorten the Profiles because of their material hardness. I've worn two saw blades to get it short. The Guides Blocks are available in two sizes (see Pictures). It's important to place the Guide blocks in right direction to avoid Calibration Errors. If only the longer Blocks available, I think it's possible to rotate the shorter left rear Block and use a longer Block there. But you need the Y-Stepper mount with Endstop (newer Version). You can use 3 shorter Blocks, but then you could get a calibration error (fixable with a small part of Wood, a Screwdriver or any other 3-5mm wide thing). After the assembly it's necessary to run the Calibration Wizard. Until now my prints with the new Y-Axis went without any Problem. Just use enough grease to avoid friction. What You need: 2x MGN12H Linear Rail Guides 330mm (in most cases 350mm, you will cut it down to 330mm) 3x MGN12 Linear Sliding Guide Block (2x long 1x short) 4x T-Nut 8mm M3 Some M3 Screws (10x 10mm, 2x 14mm) 2x M3 Lock Nut's The Rail and Rail Blocks available different qualities, just google for MGN12. My Parts are from a Chinese Shop and for around 40€ it's a very good Quality. Update 16.09.2019 added additional Front an Rear strut if needed. My Setup works better without additional struts. Update 27.12.2019 addes some Screws (6x M3x10) to the Part list THX@Jeepguy42