Brompton rollers/wheels replacement with bearing

Fully 3D-printable Brompton rollers with an bearing in the middle for easy rolling.

The rollers are printed in 3 pieces: the top part and the bottom part with a bearing and the rubber sandwiched and screwed together.

What you need per wheel:
1x Standard 22x7mm bearing
2x M4x12 scews
2x M4 nuts
1x 8mm to 6mm insert for the inside of the bearing so your wheel doesn't wobble arround with the screw. You can 3D print the insert that I have put in the files section but it's not ideal. An insert made out of metal would be much better.
1x the screw that came with your stock rollers

Print instructions

The bottom and top part are printed in ASA in my case, but PETG or similar should be fine too. The rubber part is printed in TPU.

Support is only needed for the M4 nut holes on the top part.