5.5W 450nm Laser Setup

Hey guys I’ve been reading the forum on setting up a laser and there is a bit of conflicting information between older and newer posts, so I thought I would ask the question again with my own setup.

I got a really good deal on a 5.5w laser, so I pulled the trigger (pun intended) and bought it. Now I would like to get it up and running.

The laser came with 2 sets of wires; one set has a 3 pin jst to a 3 pin jst, and the other is a 3 pin jst with 4 wires (I’m assuming the white and black are both GND) to a pair of 2 pin jst connections - from the looks of it, they are separating the 12V power and GND and the PWM and GND pins. Would this be a simple plug and play into my RAMBo 1.4 board? From what I read I would assign PWM to pin 45 on the board. Is that correct?

What would I use as the 12v source - as a precaution, I bought a 12v 5A power supply with screw terminals (should I use this or the RAMBo board?)

For more information see the photos.

I’m also using the LCD display, does this affect how I modify the Firmware? BTW I just upgraded to the latest version (RAMBo/LCD/Duel Endstops) - I dont have the endstops installed yet - but plan on it soon.

Aslo before I turn this thing on and go blind can anyone advise me on the the right goggles to use with the 450nm laser - It came with RED - but from what I read I think I need either the green or Blue ones. PLEASE ADVISE ON THIS :frowning:

I would also Love some suggestions on software to use. I have Vetric VCarve Desktop and Fusion 360 so far - is there anything else that works well with a laser and perhaps a drag knife in the future?

Thanks for all you help in advance! Thanks also for helping me with my issues in the past as well.

Color of the glasses does not indicate what laser light they will protect you from, bad assumption! My original 450nm laser came with a red/orange glasses, worked fine. I eventually upgraded to these ones


Its reassuring i wont go blind then :wink:

Does anyone have any advice for where to place the supplied wires on the RAMBo board and any other questions asked above?


(meanwhile I’m building my fume extraction hood/box/blower/thing)



Can you give us a link to the actual laser you bought? There are so many different types and they all seem to be controlled differently. You may be correct in assuming PWM, but it could easily be using 0-10V or 0-5V control as well. Plus PWN could be 5V TTL or 12V… Does it have a wiring diagram?


This is the laser. it is marked pwm and it is 0-5v with 12v power. Thanks for your help and getting back to me!\



OK, that helps a lot. The PWM is TTL (0-5V) pulses at under 15k pulses per second. You won’t be using a fan wire on the Rambo to control laser power, you’ll use a TTL pin instead. IIRC pin 44 is a TTL PWM output that would be perfect for your use. To run a laser you need 12V power, which is where your second supply will be used, a TTL enable signal and the TTL PWM intensity signal. The laser doesn’t shine without both the power and the enable, the intensity runs between 0 and 255 and is set on the fly in our gcode. You will have to edit the firmware to point to the right pins for enable and intensity.
If your laser used an analog intensity signal (0-10V) instead of PWM you’d use D6 instead and control it as if were a fan without changes to the firmware. They sometimes don’t use an enable and just set the intensity to 0 in order to turn things off.


thanks Bill. Is it pin 44 or 45? I think this is where I’m confused.

Also where is the Gcode generated? Is there software that I should be looking at - maybe another post-processor? As I said above I’m using Vetric Vcarve and Fusion…should I use something else for laser - is there another processor for laser engraving for the MPCNC?


Thanks for all your help!


Trying to modify the firmware, yet it fails to compile when enable laser and spindle control

Hi Keith!

Have you managed to set up your laser? I got a similar one to upgrade my MKS DLC v2 laser, but mine has 2 pairs from laser to laser controller, and a 3 wire jst to connect on a board. I can post photos probably after tomorrow.

In the mean time, I found a very nice software called Lightburn, although its paid, first 30days are free without limitations

The laser and the driver:

And here the board:

I’d like to upgrade to this laser, but don’t know exactly how to connect to this board, as the stock laser connects with two pairs of wires, and the new with 3 wires…