Laser light to weak when spindle speed matches, why?

[LightBurn (Oz)]

If this is what’s happening, it means that GRBL is “throttling” the laser output, most likely because you are asking the controller to move faster than it is set to allow in the firmware settings.

Read the stuff under the “Speed / Power” graph on this post:

Configuring a 3018 CNC (or other CNC-based laser) for use with LightBurn

The summary: Turn on Laser Mode to get rid of the travel lines You’re trying to move too fast, which is why you don’t get enough power You need to zero the machine 3018’s are pre-configured for use as CNC machines, not lasers, so their settings and speeds will likely need to be changed to give you acceptable results with LightBurn. To see the existing settings, you can type $$ into the console in LightBurn and press enter, or go to Edit > Machine Settings. Both are showing the same values, b…