MK4S Upgrade X & Y layer shifts by 20mm
Hi folks,
An issue has come up where the upgraded MK4S just decides to shift its origin mid print. This is the third time shit has occurred since the upgrade from MK4->MK4S and I'm at a loss. Each of the prints have successfully completed previous prints but for some reason the printer just decides to do this:
Its completely random. I have printed the above file successfully 2 times and then this happens on the third. Two other times were with two different prints that were also both successfully printed. MK4 printed hundreds of hours without issue, MK4S upgrade has dozens of hours and multiple failures.
Any ideas?
RE: MK4S Upgrade X & Y layer shifts by 20mm
FWIW, I am in the same boat - I just discovered this today.
Two things to try:
1) Ensure the printer is on a totally stable surface (this is NOT the case with mine, and I will need to adjust this in the morning)
2) Ensure the set screws are tightened on the x and y axis pullies. I suspect that mine have loosened due to 1) above (again, will try in the AM).
I am guessing that you pass x- and y- axis calibration, that the belt tension is correct, and there are no obstructions near the pullies. ( https://help.prusa3d.com/article/layer-shifting_2020)
Good luck!
Prusa is MK4S w/ MMU3 (formerly MK4 / MMU3, MK3S+/MMU2), 2 Prusa MINI+, Octoprint. PETG, PVB, (some) PLA.
RE: MK4S Upgrade X & Y layer shifts by 20mm
Are you using the speed profile? Try raising the nozzle temperature. I've found with the higher 4S speeds underextrusion is a problem. Raising the nozzle temperature can help.
Underextrusion can lead to crashes, causing the layer shift. Especially in areas of big infill where the sides are higher.
RE: MK4S Upgrade X & Y layer shifts by 20mm
I had this layer shifting problem on my factory-assembled MK4 when I started to use the IS profiles. After some time I checked and tightened all the screws on the printer and the problem went away. Check especially all the screws involved in the x and y axes, as @happykatz said. Screws on the printer tend to come loose(r) over time.