1cm radius disk with M3 hole in the middle

thingiverse

To create flanged bearings without flanges, print six discs with 1cm radius and 1mm thickness. Each disc has an M3 hole in the center and is printed at 100% infill. Insert two 4mm wide bearings into each disc, followed by another bearing to create flanges that prevent slippage. Ensure the smooth side faces the belt. Install the discs on either side of the bearings and secure with nuts on the outside for stability. Finally, install the belt and your flanged setup is complete.