This is an o-ring for the spoolholder of the Core One+

It goes on the removeable side of the spoolholder so that the bayonet mechanism stays in place once rotated onto the puck.

Get the new spoolholder from the Core One+ uprade parts: 

[https://www.printables.com/model/1486513-prusa-core-one-to-core-one-upgrade-community-versi](https://www.printables.com/model/1486513-prusa-core-one-to-core-one-upgrade-community-versi)

Why I made this:

I made my own version, because with the other models I found it was too hard to twist the holder on.

This version has a little less height than the normal o-ring that Prusa recommends for the spool holder. This is to accommodate the less squishy nature of tpu.

Print settings:

• Print in TPU (I used 94A)
• 0.2mm layer height
• 4 perimeters on 0.4mm nozzle, 3 perimeters on 0.6mm (to get the o-ring to be solid)

If it is still too hard to twist on the spoolholder, you can decrease the perimeters and top/bottom infill. Alternatively, you can shrink the model in the z direction in the slicer.