This is a spool holder for Mendel Max 2. A nice feature is that the holder itself just hangs securely on the frame without needing to be permanently attached.
To complete the holder, a 12mm tube/dowel needs to be inserted. Make it long enough that the spool will be out of the way of the Z-axis of the MM2. For this, you will need a little spacer or something to keep the spool from sliding down the tube/dowel.
The axis that the spool rotates on has a slight angle that keeps the spool from coming off the end.
This thing is quite strong by design, and can easily hold 2 spools with a good print.
One of my first FDM designs :)
I will upload photos eventually.
Edit: Forgot to mention, you need to put at least 1 bolt+T-Nut on the top part where the bolt holes are. The T-Nut goes on the side where the protrusion that holds the spool axis is.