Help with layer-problem.

[KayZey78 0]

This is a brand new Ultimaker 2 printer and I have serious layerings issue. Everytime I reach a couple of centimeters, the printer just completly goes off the mark. I have tighten the screws in the belt, as shown on Visual Ultimaker guide. I don't know what else it could be. Here is a images showing the Ultimaker Robot.

https://drive.google.com/file/d/14E2nT4bRPtzJA5c06tTY-nTpDa9KU9QOeg/view?usp=sharing

Any help? Fairly new to 3D Printing and so far i've had 2 Ultimaker 2 printers fail. One with temperatur error and this one won't even print properly. ;/

[gr5 2,167]

It's almost always the pulley on one of the motors - I can't see it very well in the photo but I think it moved in the Y direction, correct? Towards the front of the machine? So it's the motor on the back left corner. Remove the metal cover that hides the Y motor (only one screw holding it on) and push the head around until you can access that set screw. Then tighten the screw on the other end of that belt while you have the tool in hand.

The pulleys on the long belts rarely are the problem but occasionally are the problem.

[KayZey78 0]

I fixed it by reloading firmware and factory resetting. (Had done this before)

[nallath 1,120]

Reloading the firmware should not fix this problem. It could be that you simply don't see the problem anymore. Its far more likely that the problem is caused by a pulley as gr5 mentioned.