Geeetech

Addition: The right spintel nut of the z-axis I have also corrected with 0.30 mm.

Many thanks for the answer. The problem is the stepper drivers of the z-axis A4988. The right one was faulty. How many volts do they need? These are now set to 0.750V. I want to know it very well, please. Do all other stepping drivers have to have the same attitude?
Thank you so much

Hello from Germany, I have a Geeetech-A30. Bought in may 2019 and can not print yet.

Modell: A30
Serial number: 180922A3000040E
Firmware version: V1.38.59
Hardware: V3.1

The two z - axes do not move synchronously. The right z - axis changes in height about 2mm.
I checked and corrected the ...