Ball Bearing Kit for MMU3 Spoolholder

Replace the plastic wheels in the new spool holder design that come with the MMU3 (Newest design as of April 2024) with ball bearings using these simple two parts. Print in PETG 100% infill for strength. 

Also add a PC4M10 Jack to the spool holder using this - https://www.printables.com/model/859541-mmu3-spool-ptfe-holder-with-pc4m10

Video here - 

For each wheel print out two ‘rods’ and one ‘casing’.  Use 7x22mm ball bearings (the same ones that came with the MMU2S and older types of spoolholders). Snap the bearings into the casing, which has three tiny chamfered nubs that hold it in securely. You can easily push them out too.

Once assembled, the two rods, casing, and bearing form together to create a 3D shape the same shape and size as the plastic wheel. (Actually I widened it a little more so the side rods are a little wider so the center wheel is positioned better in the center as I noticed there was a lot of side to side play with the plastic wheels.)

Open up the spool holders and swap out this assembly for each plastic wheel - four wheels per spool.

Includes fusion file and 3fm for printing four of these for an entire spool, which takes 32 minutes. Print in PETG at 100% infill .2 layer height.