I love the way how I can adjust the original holders, but there was a problem with the first, and multiple holders will create unwanted 4mm non-usable space each, in some scenarios having 2cm space more is wanted.

Thank to that master holder you will save more space in the box, and thanks to different rails dimensions you can create your own customized one.

I printed bearings components using PLA 0.2mm, all other 0.3mm. 
For double-sided bearing holder add supports on the table.
For the bearing roller make sure you set randomized seems. It will create more rounded surface.

UPDATE 09.08.2023 → New bearing roller
UPDATE 10.08.2023  → Bearing components are now thick enough