Lack Enclosure MMU Buffer

A better buffer system designed after this one that I used until I built the Lack table enclosure for my printer. This buffer is basically the same, but only requires a single 408 bearing and easier assembly (since no extra wheels for the spool mount).

Assembly:

1. Insert a 608 bearing into the filament wheel. It may take some slight force to get it all the way in.
2. Place the wheel inside the buffer.
3. Place the hex bolt through the hole of the buffer, filament wheel, and out the other side of the buffer. Make sure the head of the bolt is on the side of the buffer where it can lock in place.
4. Tighten the nut onto the end of the bolt. It doesn't need to be very tight, the wheel should be able to spin freely (small amounts of friction are fine).

To mount the buffer you simply need two M4 screws (M3 screws might work as well). Pre-drilling holes into your mounting surface will make it easier to screw it in. The buffer should be angled such that the taller side is pointing towards your spools. The PTFE tubing that leads to the MMU can be inserted into a hole on the other side.

Usage:

Insert the filament into the hole nearest to the spool and loop the filament around the wheel twice. The left side of the base is curved to guide the filament up and around the wheel, the right side has an overhang designed to catch the filament so that it will go through the PTFE tube into the buffer.

Printing:

Material: Any. I did PETG, but that's just because I mostly use PETG these days. PLA should be fine as well.
Layer Height: 0.2
Supports: None (assuming your printer can handle 40º overhangs)

I included the individual pieces as STL files, but there is also a 3MF that includes all the files in the correct orientations.

Demos

Filament Loading: 

Filament Unloading: