Yes, I change setting on both, grbl and stepper driver. Also tried climb vs conventional, climb has nicer finish, but result is same wavy pattern. I milled cube 60x60mm, after measure its 60x60, so it is very precise.
Shallow has same result. Machine is very solid, no bending, so it does not matter if I cut on left side center... I tried it.

Could it be something that I use GRBL Shield attached to Arduino Uno and somehow pulses from XYA can influences themself ? (I have no steppers on them, I use only side pins for step/dir, cloning Y on Arduino Uno is not cable friendly). I do not understand electronics, so maybe...


Here is codefor 45°:


G0 Z2.
G0 X100.621 Y199.616
G1 Z-15. F400.0
G1 X199.616 Y100.621 Z-15. F1800.0
G2 X199.616 Y97.369 Z-15. I-1.626 J-1.626
G1 X100.621 Y-1.626 Z-15.
G2 X99.011 Y-2.3 Z-15. I-1.626 J1.625
G2 X97.369 Y-1.626 Z-15. I-0.017 J2.299
G1 X-1.626 Y97.369 Z-15.
G2 X-1.626 Y100.621 Z-15. I1.626 J1.626
G1 X97.369 Y199.616 Z-15.
G2 X100.621 Y199.616 Z-15. I1.626 J-1.626
G0 Z2.