MMU3 R4 Casette With 608 Bearing

I've remixed the MMU3 Buffer R4 cassette segments and wheel to fit a standard 608 bearing and not need the central shaft. This model also implements the loading aid originally designed by @ticat_105850 and remixed into the R4 cassettes by @bluex.

The wheel was split into two parts for easier printing. I suggest applying a bit of super glue between the two halves after the bearing is pressed into them and spinning them in opposite directions to spread it evenly, as they have a tendency to warp a tiny bit and not sit flush with one another. 
I've also added space for another m3 screw and nut that goes through the center of the bearing for extra rigidity. Don't over tighten it or you risk breaking the plastic that goes through the bearing.

Print using 0.2mm layer height, I opted to use variable layer height as well. Use about 20% infill and 3 perimeters. No supports are necessary.
I've printed the parts in PLA as my buffer is outside of the enclosure and shouldn't get too hot.