All of a sudden the lasercutter cut very uneven lines in the x-axis direction as you can see in the following picture:
The laser-head is very has a very simple build-up, so i quickly suspected bad bearings in the little white wheels that the laser-head rolls on. I contacted cnccheap where i originally ordered the machine, and they where very fast to respond (the same day!!). for $100 they sent me 2 sets of white wheels and spare lense and mirrors. It took about 1 week for the parts to reach me (in Norway) from china.
Here comes the how-to fix:
When you start to mount the 3 new wheels again you should start with the bottom one as it is the most difficult one and much easier when the whole assembly is loose.
Ater the wheels where changed i run another line-test to see if the fix midigated the problem.