Vector raster problem

I have a home made laser diode engraver using marlin 2 as firmware.
I have trouble engraving a filled vector SVG image.
Using gcode generated by laserweb, most small areas became unfilled (laser bean runs too weak to burn the wood in small areas). It appear that the laser adapts to feedrate or something and it is full power only when feedrate is full. In small areas, deaceleration starts before ending acceleration, and full framerate never comes. (it is what im guessing)
I tested the same image with a gcode generated with lightburn and it went well. I guess its because of otimization used in laserweb, that engraves by regions when other softwares engraves running full raster lines at a time (if you understand me).
My question is: theres some way to change the raster operation so it will burn entire line at a time, instead of regions? Or, does someone know how to configure marlin to perform better engraving small regions? I can turn off the trapezoid thing, but i afraid it can cause other problems.

There are quite a few unknowns here, but I’ll have a guess.

It sounds like you are describing a proportional laser mode. This is applied by the Firmware, which will scale back the laser power when the head is moving slower than the desired cut feedrate.

  • Do you have any of the laser features of Marlin2 enabled?
    • Did you upload the firmware yourself?
    • It’s all a bit confused in Marlin-land, different v2 versions support differing laser features.
    • I do not know Marlin too well so maybe there is tuning that can be done on it’s proportional power map. Or maybe it can be enabled/disabled in startup gcode.
  • Have you tried increasing the acceleration in your firmware? Firmware defaults for this are often quite cautious.

I am assuming you are talking about the Laser Fill Path operation type?
Laser Fill Path is often best combined with a Laser cut (or laser cut inside if doing very fine/precise work

  • Do the cut operation first, this will do all the paths and outlines of the areas to be filled. This firms up the edges for the path fill operation,
  • Then do the fill path, which will infill all the areas and ‘firm up’ the very small ones.

You can also try Laser Raster Merge operation on the svg, that will raster the whole work in one pass as you describe lightburn doing.

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