Can you show a screenshot of the banding in lightburn?
Where you say ‘horizontal’ -is that the path of the laser as it ‘scans’ the image or at 90 degrees to it?
i.e. if its 90 degrees then the laser is burning n-number lines correctly followed by n-number lines feint.
if its the path, then the laser is going light-dark-light-dark (as mine below)
The badly drawn arrow shows direction of burn travel
I don’t believe it is Lightburn doing it. It would have to generate LOTS of power high/ power low type gcode instructions to do that. I don’t think it is.
maybe the laser is losing power to the motors as the stepper motors pulse
maybe the psu or laser driver board is pulsing the output
maybe settings related to acceleration or jerk (note the even darker bands at both ends of travel and the banding is more pronounced at each end)
The bands on there are about 0.7mm apart.
I’ve not had much time to experiment or try to relate it to anything mechanical or electrical.
It doesn’t obviously relate to belt pitch.
Hoping someone who knows about diode driver circuits might chip in. I think they (are supposed to) hold the current constant. I wonder if they could oscillate somehow.
I’ve not exactly helped you here. Bumped up your post though.
Let us know any results you get.
Alan