Another Full Spectrum 5th Gen conversion

Hi all! I recently got a used Full Spectrum 5th Gen laser, and the control board is… haunted. It does random, crazy things when I connect to it from my PC.

My board is the same one shown in:

So there are good posts on the forum to help me out here!

I have a plan 2-stage plan in my head.
Step 1 would be moving the PSU and the (new) control board external to the laser… possibly using a PC case so I can easily get to the wiring. Then use the laser for a while and get used to it.
Step 2 would be expanding the existing cutting area to either the full size of the FS case or a larger custom enclosure.

I’ve got a kind of crazy question though…

Since a lot of the details for swapping the board out seem to be around tracking where the lines go from the FS power supply… would it make it significantly easier if I got a different power supply, since I’m swapping major parts anyway? Or would it be pretty much the same?



Hi Michael,

Welcome to the forum! Sounds like you have a fun project ahead of you… Please share your progress along the way.

Swapping the PSU is completely your call, depending on many factors, but that part of the process is probably going to be pretty similar, regardless of power supply type. Which model PSU do you have currently? A picture would help (see our LPSU Guide).

Does the machine work at all currently or can you even test it with the connection issues? I recommend making sure everything functions and getting used to the machine before making any major upgrades to it. Many considerations are going to depend on your comfort level and time availability to tinker with the machine.

If you have any questions, we’re here to help.

Current PSU in the machine:

(and I can take more pics if needed.)

The machine sort-of works, but like I said, it’s haunted.

If I power it up not connected to the computer, the buttons on the faceplate work to select options, move the laser head around, etc. But the laser won’t fire for more than the tiniest spark. Just enough to see in the dark.

If I connect to it from a computer… well first off it won’t connect by picking the type of laser it actually is, but if I select a different Full Spectrum laser it connects, and it IMMEDIATELY starts firing the laser at some random power setting. Also the buttons which worked before to move the carriage around now do things like make the carriage shake left and right instead of move.

Unfortunately Full Spectrum does not have the firmware around for re-flashing a board this old, and it may just be shot even with reflashing, so I figured it’s best to replace the board with something much newer so I can add things like a camera.

Hi Michael,

This PSU is slightly different than the ones I’m used to seeing. It looks like it has a 4 pin, 5 pin, and 3 pin set of screw terminals. Can you get a picture angled from the top where we can see the silkscreen on the board pins, please?

Those sound like some concerning issues to start with right out of the gate. While getting a new board with properly functioning firmware may solve some or most of it, you may want to run your symptoms past the community over at Maker Forums and see if they can give you some insight on getting those issues resolved before introducing new variables to the equation.

1 Like

I had to remove the PSU, but I got good pics of the markings on the board. I added those pics to:

On the thread:

There’s a link to the FSL 5th Gen laser schematic.
Mine looks identical EXCEPT that I’m missing one “G” terminal in the center block. (Which, in their diagram, goes to the lid safety sensor.)

And I did try troubleshooting the board issues with Full Spectrum themselves, but we couldn’t make the system act right. I’d rather have a more modern board anyway with a camera and better features. So I’ve ordered a Cohesion3D board this morning. : )

Hi Michael,

Thanks for the pics! Yes, the LPSU in that schematic is the known 4 pin, 6 pin, 4 pin variation that we are familiar with and is covered in our LPSU guide.

Along with the “G” Ground terminal in the center block, yours is also missing the far right “L” terminal on the right block of the LPSU (see pic below, flipped to match your picture orientation).


It’s the first time I’ve seen a power supply that excluded it. The model in the linked article did not have a wire to the L terminal anyway and the schematic shows it is “unused”, so that may be why the manufacturer didn’t bother to put one on it. For that article, they tied IN to 5V, so you would follow that same logic.

Good luck with your install! Let us know if you have any questions.

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.