y-axis linear bearing randomly seizes and bearing question
One of my MK3S had a problem where it would seize up on the y-axis. Right before I was going to replace the bearing with new ones I noticed while fiddling with the bearing on the rod that the inner rubber rings (indicated below) on some of my bearings were slightly torn up and were not whole rings any more.
1. The bearings were working most of the time so would I be correct in assuming that this torn rubber could cause the bearings not to move easily if pulled down and wedged in-between the rod and the bearing?
Using an exacto knife I cut the rings off the worst one and it seemed to work fine with me just gently moving it up and down the rod afterward though this is not a perfect test.
2. However if the rings were the problem would there be any problems to cutting the rest of them off and continue using the current bearings?
3. Lastly if I'm correct on the first question but the rings are necessary, how do I go about making sure that the bearing rubber rings don't get torn apart on my new bearings?
The rubber is intended to seal the bearing from picking up dust and debris and to retain its lubrication. If you remove them, it'll cause the bearing to pick up that dust and it'll seize up the actual ball bearings inside the sleeve sooner than if the seal was properly functioning. If the seal is damaged, you really should replace it eventually, but it should be fine for a short time if you need to use the printer in the short term.
The seal shouldn't be tearing up with regular use. If it tore it was probably either a manufacturing defect, or it caught a sharp edge when being installed on the smooth rods.