I was cutting 1/8" acrylic using the profile from the library in Lightburn. The settings for that profile are 0/100% min/max and 50mm/s. I checked several other common profiles and they all had 0% as the minimum, as I would expect.
I changed the min to 1% and it cut with no issues.
Not sure if anything changed - or if anything is even “wrong” - but I thought I would mention it because it is different than my (limited) experience.
My understanding is that the minimum power setting only kicks in while cutting, when the laser head has to slow down (for example when moving through a tight arc). If it is set to zero, it will switch off the laser, as it moves slowly through the tight arc, and it may not cut these tight arcs (Example, the corners of a square, where it has to slow down to change direction). I also understand that lasers have a threshold, below which the lasers turn off anyway. I believe that anything less than 10% on Dorian is considered zero, and the lasers don’t fire.
I have been puzzled by the error message too, and wonder if some setting has changed. Danny Miller recently indicated one should not change the minimum setting, just leave it at zero, but did not tell me specifically why. I am hoping to learn if something has changed, and if my understanding of the setting is incorrect. If my understanig is correct, then your cut should not have been good.
I set my m minimum setting at 2% and didn’t get the error message. I figured it was low enough that it wouldn’t do any damage. Didn’t get the message to leave it at 0.
It’s a software “feature” they added in the latest version of LB. It is baffling that they put in this nuisance warning. I’m asking them to please remove it.
The controller will automatically scale back power when it is accelerating/decelerating and thus not at the commanded speed, to ultimately produce the same joules per mm of delivered energy. It’s not just tight arcs, all starts/stops/corners do this.
The scaling goes between min and max power. The best (and simplest) figure would be 0 for min power that they’re tuned for and it performs quite accurately even on difficult cases with no fiddling around.
A higher number creates overburn, which usually doesn’t get noticed but it does reduce the tube life. Overburn is very noticeable if you’re trying to do light vector (not raster) engraving on acrylic, the burn depth increases on vector starts/stops and tight curves, and often spikes all the way though the material on the corners.
