Command to turn laser on/off

Hello All,

I finally found the time to put my beta kit together! It was a fun build!!

I’ve been testing with serial commands, as I have no experience with LaserWeb and want to simply make sure the hardware is working correctly. $H homes beautifully, but I haven’t been able to power on/off the laser via software.

Does anyone know what the command is to enable/disable the laser, and/or is there a test file (gcode) that I could use for testing?


M3 and M5 should turn the laser on and off, respectively. Be very careful when issuing these commands and be prepared to cut power to the machine if something goes wrong.


No change with M3 and M5. Controller responds with “ok” to both but laser stays in the low-power dot mode at all times.

The LED on my laser is flashing orange; is this normal?

Update: I think the unit was in focus mode; toggled via the on-laser button and tried the M3/M5 commands again with the same results (e.g. nothing happened).

Yeah, flashing LED is focus mode. Note, M3 requires a power level technically. Try M3 S100 (10% power since the range is 0 - 1000)
If that doesn’t work recheck your wiring to make sure that 12V/Gnd/PWM on the controller go to the same on the laser. Please note that you can’t really always trust the color coding on the cables. Look at the controller AND the laser and absolutely confirm that the wiring is correct :slight_smile:

That worked! I charred a nice hole into my workbench top :slight_smile:

Grbl 1.1h [’$’ for help]
[MSG:’$H’|’$X’ to unlock]
M3 S100

LOL… oops. Yeah, should’ve mentioned to be ready to turn it off quickly. Or told you to do 1% not 10%. Sorry about that. Glad it works now.
What software are you planning to use?

I’ve started using Laserweb, but am open to other suggestions.

LaserWeb will get you started… but when you start feeling the pain of it’s slow speed and lack of design features, check out LightBurn :slight_smile:

Will do! Thanks for your help :slight_smile:

We really like LightBurn, and not just because we’re biased to.

1 Like

Haha… yeah, to be 100% honest, I work on LightBurn. But it’s because I really like it. Not that I like it because I work on it :slight_smile:


Getting things dialed in nicely…

Excellent :slight_smile: Nice and crisp!

1 Like

That wouldn’t happen to be a piece of the box that the parts were shipped in, would it? :smile:


Best thing to test with is the box it came in.

1 Like