Laserengrave plugin

[3d0g]

Just getting started playing with the Laserengrave plugin and I'm seeing some registration errors between the L to R and R to L passes. I'm relatively certain it's not my machine as I've done some gcode to mimic an engrave, running the head at max speed back and forth along the X axis a few hundred times and when I manually fire the laser, it always hits the same hole exactly. A rounding error in the pulse calculations for the reverse run, perhaps? Is there any way to see the code for this plugin? Has anyone else experienced this?

Cheers.

[cncdrive]

Looks like a backlash on your machine.
Try to run a g-code the same way from L to R and then move one line up or down and R to L and repeat.

No g-code is created when using the laser engraving plugin, because it would be a waste of program memory.
Imagine that for example a 2 000 x 2 000 pixel graphics is 4 000 000 pixels in total and this can be coded with 4 000 000 bytes using the 0-255 PWM value range per pixel,
but when the same is represented in g-code then each pixel would be one or more lines of text and even one character is 2 bytes.
That would be around 15-20 characters per pixel which is 30-40 times more memory and so it would be 120 000 000 to 160 000 000 bytes.
Ofcourse I just calculated an avarage approximately.
And a picture image could be even larger than the mentioned 2 000 x 2000 px.

[3d0g]

Backlash would have shown up on my test gcode; in fact, that's why I wrote it to confirm. I also never had this issue with LinuxCNC and its raster engrave plugin. Other ideas?

[cncdrive]

No, I have no other ideas.

[3d0g]

Source code no-go?

Does Laserengrave honor the UCCNC axis backlash compensation settings? While this doesn't appear to be a mechanical backlash issue, it may be a way to compensate for the plugin error...

[3d0g]

(answering my own question...)

Yes, Laserengrave honors backlash settings. I just need to remember to enable / disable X axis backlash when doing engrave jobs. I can live with this. Looks pretty good now.

[3d0g]

(last post)

And here's what happens when I forget to remove the backlash after an engrave job.