Evening project: control multiple diode laser modules within one LightBurn job

In a forum, we had a discussion whether you can control the amount of individual diodes within one laser module to optimize the behavior. At a 40W module, you could use only two diodes (10W) for engraving because the spot is much smaller. For cutting, all diodes are used. This is already available from some manufacturers, but using hardware switches.

But there is no way to do that on-the-fly. And that inspired me to do a little test. I used a middleman board to read out the laser signal and then split it into two control signals. So you can select the module or the module strength in LightBurn with the power setting. Of course, it would be better by firmware command, but then you would have to teach LightBurn a new gcode command.

The small board switches on the first module at 0-50% and the second at 51-100%. The power is then interpolated back to 100%. So you lose half of the resolution, but that should hardly bother :slight_smile:

It doesn’t make total sense, but as a proof-of-concept it was fun :slight_smile:

In the video, you see two circles, both engraved with either module. It’s only controlled by the power setting which module is selected.

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My Ruida will control two lasers (tubes) simultaneously… I’ve never had the opportunity, but many do.

Isn’t this the same ?

I know it’s not gcode, but I’d think some of these newer controller might have the hardware to perform the operation.


I don’t know, I don’t own any Ruida controller :slight_smile: But this is not exactly simultaneously, in this case, you can choose which module you want to use by adjusting the power level. So it’s kind of online module switching.

I meant, the controller, via software controls each tube separately… Run them together or separate, doesn’t matter… I haven’t run one of these, I just know they are supported and the options are there. Notice under laser 2 is the 2nd set of max/min for the 2nd tube.

Haven’t looked for a grbl board that handles multiple tube machines… maybe it’s rather uncommon, but seems to be alive and well with industry.

Many of these new machines include double lasers, such as the laserpecker 4 with the additional 1064nM ir to it’s 455nM blue visible light… Wonder how they handle this…? I think they are grbl based… :thinking:

Some of these Ruida handle dual tubes/head … don’t know how they work it out…


Oh, that’s great. I don’t have any other machine than diodes, so I’ve never seen this before :slight_smile: I think with grbl this is not existing because there is no command to change the modules (at least I think so, there might be some tool change commands that could be used, I have to check again :slight_smile: ).

That’s what I was speculating about the LaserPecker 4 and other similar machines have two diodes. From what I understand you can select it… don’t know if it’s a software option or you need a :point_up:


I know that the Ikier has a manual switch:

As well as the new CooLook:

But I don’t know how others are handling it :slight_smile:

If you can do it with a switch, you can do it electrically via software with the right hardware.

Seems like the coming thing…

In the end, you want to control both via software…


Diode using half Power:
In Snapmaker 2.0 A350 40W laser, the Luban software can let you switch between full 40W power or the 20W half power. I understand in Lightburn 1.5.0 there full support for the machine, so I do hope this is included because it will improve engraving using a smaller beam at less power.

This is from the beta 1.5 release and the only mention of snapmaker is this

[AH] Enable inline power mode for SnapMaker (available with recent firmware update to some machines)

Assume you can’t access the beta area, but that’s the link so you can try it.

If it’s what you are after, might ask about becoming a beta tester so you can help us test it.

Maybe @johnjohn can be more helpful.