Ball bearing to build a filament spool holder. I planned to print 4 pieces per spool and mount them on 2 threaded rods. This would create a kind of bench with spools of filament.
Additionally, you will need 8 x 6mm BBs (e.g. BBs). If you want, you can use glue to fix the upper, inner part of the bearing.
Dimensions: inner diameter 8mm, outer diameter about 30mm, thickness about 9mm
To extend its service life, you can use a little bit of grease.
The author remixed this model.