Built my MK3s as a kit and a few prints in got a squeaking noise from the Y axis. From reading the forums others have seen the same on the X axis also.
These washers go either side of the idler pully. Both have a chamfered side that needs to be inserted towards the centre of the bearing. Then when put back together the bearing will be griped properly and prevent the pully from rubbing up the sides or the yoke. Just don’t do the bolt up too tight.
Don't take long to print, printed in PETG, 0.2mm Quality
The author hasn't provided the model origin yet.