RE: Noisy bed on MK3S
So I too had the loud Mk3. Especially during start up with the Z axis moving. I greased the bearings thoroughly with no results. I did determine it was from the right single bearing assembly. I had the unit on its back and could tap the bed. I could hear the rattle. I took a pointed dowel and jammed it between the bearing and the bed frame and the rattle stopped. This meant that the "U" shaped housing wasn't holding the bearing securely although the screws were tight. I took off the U housing and placed a small square of 1/16" dense foam between the housing and the bearing. Replaced the housing to secure the bearing in place. 90% of the rattle noise was eliminated. I'll probably do the other 2 bearing housings. I believe the remaining 10% is coming from there.
So much better.....