Update 25/11/2019
Update: added a little more play in the bearing for better function without adjustment.:

This spool holder is attached to the chassis of the MK3 prusa as the original. It keeps the plastic roll by preventing nodes from forming around the axis of the support.
No need any ball bearing, the bearing is based on a 6mm soft ball recirculation system.
Only 2 parts to print for each support.
3MF prusa slicer project files joined

https://youtu.be/ZZHaaujGAA0

Prusa

I3 MK3S

No

No

0.15

20

20% infill, 2 perimeters, 4 top and 4 lower