Monoprice Select v2 Mini Z Carriage

I wanted to do the well known NEMA-17 Z-axis mod (https://hackaday.io/project/14823-monoprice-select-mini-maximum-3d-printer-mods/log/55525-upgrade-the-z-axis-with-a-nema17-stepper-and-tr8x8-leadscrew) but for some reason I found my printer's Z axis carriage didn't quite match the one in that guide. The leadscrew wasn't removable (and also had its own issues coming loose within the unit sometimes), and I couldn't upgrade the rod without modifying the carriage or printing a new one. There were a couple of existing Z carriage models I found, but for some reason whenever I would install them in my printer the carriage would seize up and be unable to move. I eventually discovered that for some reason my particular model of the MPSMv2 had the Z rods spaced slightly different than other models (I wasted a lot of bearings while discovering this). I ended up remodeling it completely from scratch and included an adjustable z stop mount that fit the current extended Z axis mod I was using (https://www.thingiverse.com/thing:2420910). I've included the source files so if you don't wanna use that mod too you can adjust this model to your liking.

To install this you'll need 3 LM6LUU bearings (they end up fitting tightly enough to be impossible to remove and you'll likely need a vice or something to get them in) as well as a leadscrew nut if the carriage you're replacing has an integrated one (lots of details about all that in the guide linked at the beginning of this description). The adjustable Z stop needs a long M3 screw, M3 nut, and a spring to add tension.

I printed mine with Cura's tree supports.