Makerbase MKS SERVO42C PCBA NEMA17 Closed Loop Stepper Motor Driver CNC 3D Printer Parts Prevents Losing Steps for Gen_L SGen_L

I got these for my SecKit SK-Tank. They are a nice upgrade! The TMC 2209s I had before were a huge improvement over the 8825s on my previous printer, and these are even smoother and quieter than the 2209s, so much so that I think of these as 'butter drivers'. You will get more torque, with less heat in the steppers. And they are closed loop, so you're basically immune to layer shifts. From the documentation I seem to remember an upper limit to how fast they can go, but it's really high unless you have a crazy fast printer and are trying to do speed benchies or something. They handle my normal speeds (100-150 mm/s) just fine.

I blew up 2 of these before I got them working right. I wanted to see how well it would slip and then make up the missing steps and since there is no current control, when I drove it manually past it’s position it overheated the mosfets and actually started them on fire. The only way to save the motor in an overdrive situation is to turn on protect mode. In that mode, if fully disables the motor in an over current situation and then it defeats the whole purpose of a closed loop motor. Once I got this working on my printer I then had salmon skin problems on the curves of my print. i tried everything from 16 to 256 microsteps but when I went back to my TMC drivers the salmon skin went away. I feel like these motors have potential but for now the firmware in them is not up to par for me to rely on. All 3 of these that I ordered were the 1.0 version. I see MKS does have a 1.1 version that adds current control but there is now way to upgrade the firmware from what I can tell. And their GitHub does not actually have the 1.1 bin file anyways. Maybe the v1.1 is better but I was unable to get one with the new version on it.