Laser engraving with duetwifi - connections

[Progress]

Hello,

I would buy a laser diode 6W for engraving, to mount on the head of my 3d printer selfmade with duet Wifi.

But I'm not very sure if I can connect it.
I'm using 24v on duetwifi and this is ok for the laser, but it need a 0-5V input for power regulation (I can use an external potentiometer ) and I don't understand how to connect other cables to turn on and off the laser.

I think to need to use the laser at minimum power to simulate and center the figure, and at high power to engrave.

the laser and instructions are in this link : https://optlasers.com/en/jmsblog/aktualnosci/51_plh3d-6w-xf-laser-head

could someone help me to do this?

[resam]

I'm currently building a similar setup - not fully tested yet, but I think the basics work.

I am using the HEATER_3 pin on the expansion port, which is a 5V output.
You can use "M452 P3" to enable the laser mode (maybe need to use I1 to invert your signal), and then use "M3 Sxxx" and "M5" to control your laser power setting. Make sure your software that generates your gcode supports this gcodes! Not every software produces compatible files.

[cgcafer]

Hi Progress,

I am using this Laser, https://www.aliexpress.com/item/Free-shipping-15w-laser-module-high-power-blue-color-laser-head-DIY-engraving-450nm-lasers-DIY/32801509554.html?spm=a2g0s.9042311.0.0.DZ4FEn
and i use https://www.aliexpress.com/item/TLP281-4-Channel-Opto-isolator-IC-Module-For-Arduino-Expansion-Board-High-And-Low-Level-Optocoupler/32672253659.html?spm=a2g0s.9042311.0.0.8xq2MI this opto coupler.

My printer power supply is 24V. If your fan voltage selection is 5V you don't need to modify opto coupler input resistor which is 220Ohm, but if you are using 24V for fan, you should change related input line's serial resistor with 2.2K. and I use FAN2 for controlling laser for that i add this lines to config.g file

; LASER SETTINGS
M106 P2 I-1
M42 P22 S255 ; FAN-2
M452 P22 R255 F200 ; switch to laser mode using the FAN-2 output pins to control the laser

after that you can use laser by using M3 S1 (laser power 1 unit) or M3 S255 (laser power is full) M5 laser off

[Progress]

thanks guys,

So, you use the fan output to control laser power and on - off

my fan are 24V, so i need a resistance…

@cgcafer that laser looks nice...it's a 15W.... but it's the real power? It's a lot for that price. Do you have some videos?

[cgcafer]

Hi,
unfortunately 15W isn't real power it has average 8W.
But it can mark black anodized aluminum plate with one pass (F500). And It can cut 3mm wood with 3-4 pass.
Now i haven't any video and any picture, because my printer has a changeable head and now it is plugged in over 4nozzle filament head.