Hi @kempski
I’d first start with the usual:
- make sure your frame is well alligned (really square)
- motor arm is perpendicular to the frame
- belts are tight enough (but not too much)
- motor gears are not loos on the axel
- etc…
You can take a look at this post for the frame squareness: Falcon 2, Frame out of alignment
I’d also suggest you read this post about the tigntness of the belts: Falcon 10w laser misses the mark on second pass
Let us know if the above is giving you a start on fixing your issue.
Cheers!