Y axis shifts in middle of print on MK4S
This morning I was greeted by a pile of plastic spaghetti on my print bed. After printing the same file multiple times the Y axis suddenly started shifting part way through the first layer. I stopped the print and restarted, the Y axis shifted in the exact same place. It happened again a third time, so just for fun I let it run through the second layer and it skipped two more times in other places, and now I'm here. The X axis and Y axis recalibrate before each print, something it did not do after the upgrade, but recently started doing. When the bed is manually moved to the rear it is jerky, but when I use the software to move the Y axis it is smooth. I have the latest firmware, and have used it for several weeks. Do I need some sort of software reset, a new stepper driver, new stepper motor, or something else? BTW, the belt is fine.
RE: Y axis shifts in middle of print on MK4S
I've had the same problem.
To me the belt from the bed looked okay but after tensioning it a little bit tighter the problem was gone.