Anycubic Kobra Max, Kobra 2 Max and Kobra 3 Z axis thrust bearing shim

I've fought with inconsistent Z axis movement and poor bed mesh with my Kobra 2 Max since day one. On multi item full bed prints or sometimes on taller prints, it seemed like the z stepper movement wasn't always translating to a full layer height of lift. I recently read that the Kobra 3 crowd was able to make some improvement by implementing thrust bearings on the Z axis so that the motor shafts were no longer were also supporting the weight of the X gantry.    I picked up a 10 pack of Uxcell F5-11M thrust bearings on Bezos Express for $10 and created a small adapter in Fusion 360.  In hindsight, I could have used F6-14M instead but these small guys still seem adequate.   

*Update*   These also fit the original Kobra Max.   I have a couple CR-10S Pro I will try them on also.  I suspect they may end up working on a number of printers.   If the opening in your stepper motor bracket is roughly 22mm across and the stepper shaft is 5mm, give em a shot!

*Update Again!*  I bought a Kobra 3 and these are a perfect fit on that printer as well.  I'd won't be surprised if they also fit the Kobra 3 Max and the Kobra 2 Pro.

I was able to get my first full plate print (TPU at 100mm/s with a .8 nozzle!) after installing them and retramming the gantry.   I have to also give some of the credit to @Mark4jr_1711935 because his excellent YouTube videos and spacers to allow the use of silicone bed spacers and steel standoffs which drastically improved the bed mesh and got it into the range that the printer can actually do an ok job compensating for.

I printed these in PETG on my original Kobra Max and it was my first time printing PETG on it so its ugly!  I went with 5 tops and bottoms with and 3 perimeters since I use a .6 nozzle.  20% infill is more than adequate.