Have had someone such a problem?
3 days ago I printed normally. All looked OK except THIS problem, bet prints were good enough for me.
Without changing almost anything, I noticed that the print have a problem - it shifts on the bottom part by "Y" axis.
Yesterday I made 3 tests. The object for print was 20 x 20 x 20 mm "cube" with 2 mm thick shell and missing TOP / BOTTOM side.
The first try was sliced with Cura Engine.
The result was: THIS
After than I decided to scale X Y to 10 mm and leave the Z as is - the object! Again sliced with Cura Engine.
The result was the smallest object in front - HERE.
At the last I decided to change the slicer - I tried with Slic3r. And the result is THIS one in front..
The pictures are not good enough, but trough a magnified glass I can see that the first 2-3 layers are OK. Than the shifting begins and continues 15-16 layers. After than the print is absolutely vertical - OK. And the "effect" occurs on the all 3 prints no matter of size of the object and the slicer !!!
The first think was that the pulley of Y motor is not tightened enough, BUT the motor arrived with the pulley heavyset on the axis. There is no way to tighten it more.
I tried to tighten the belt too with heaviest springs - without result.
I think that the problem is not mechanical or electrical, because nothing was changed from before and because if it IS, the shifting have to occurs on different layers.