hello
I’m a beginner on lightburn and I’ve read a lot of content on setting speed and power. But the question of parameter priority remains unclear to me.
in grbl the speed $30 is apparently given in mm/s and in lightburn it is given in mm/min for diode lasers. Does lightburn do the equivalence in auto ? in test material ? in layer ?
Speed and power can be entered in different places: from the material library, from the layer, from the shape. Are there priorities that are respected?
From my tests, if I put 20% power in the material library, and 50% power in the layer and 80% power in the shape, it seems to make a 20% line. But if I put 100% power on the layer and 5% power on the shape, it seems to make a 100% line.
in filling, I do not obtain any shade of gray whatever the parameters; it’s black, burnt or nothing…
maybe this is something I misunderstood but with a power of 3% and a speed of 60mm/min, the cardboard burns over its entire thickness of 3mm
thank for your answers.
note: add the possibility of hiding (not engraving or cutting a shape) in the shape tab: I made a grid to test the materials, but I have it print the lines one by one because according to the results it is not useful not much to increase in power or speed. (the paper does not need me to test cutting at 100% power on 60mm/min)
$30 defines spindle speed and is represented in revolutions per minute. However, from a laser perspective the value here most simply means “value that represents 100% power”.
No matter the units used, LightBurn will convert and show you the appropriate value. Actual absolute requested speed does not change irrespective of the units, assuming that your controller firmware is working correctly.
The material library is a passive library and does not directly influence speed on its own. The only times it comes into effect is if the Cut layer is either assigned or linked to the library. Assignment simply copies the values from the library but does not continue to be tied the library entries after that. When linked, the material library values are directly referenced and changes to the library will carry forward to the Cut layer setting.
Power scale at the shape level scales the power from the Cut layer setting.
The Cut layer settings are the starting base for all power/speed settings. In the case of shape properties it can scale power based on the original settings but does not establish an original setting. Power scale is percentage of power between min and max power.
This should be 40% power. Material library is disregarded. 50% * 80% = 40%.
This doesn’t make sense to me. It should be 5% power. There may be something wrong with the setup if that occurs.
I suggest you leverage the material test feature. This will get you a much better familiarity of the effects of your laser on material. Subtle changes can make large differences depending on the material. And the difference between too light and completely black could be very narrow.