Lost beam! Won't engrave, or barely scratch surface?

I am using an Aeon Mira 9 CO2 laser with HP elitebook laptop with windows 10 at work. I just got my machine up and running. First night made 6 4.75" X 1.5" acrylic placards. No problem. Next night, I tried to make 6 more, but the engraving was not as deep and didn’t cut all the way through the plastic. The third night, I stopped the job shortly after it started (about a minute into a 6 minute job). And now I don’t have any type of cutting/engraving going on.

Tonight, I realigned my mirrors, mirror 2 was well off the mark, and mirror 3 was slightly off. Corrected both issues. Pulse function works fine. I used the “Focus test” under “laser tools” and the laser probably went 50% as deep as it should. When I tried a new project, no laser beam. It’s like the beam is turned off, but I can pulse, and the faint engraving of the focus test.

I have seen people post their $$ info, but when I open my “Console”, I don’t know how to select it to type in it. But I will include screen shots of my settings:

Started with this:


Changed to this:

So for all of my confusion and thank you for your help!

I hope you saved the original configuration before you started modifying it’s contents …

How long have you had this machine?


When you have any kind of failure, especially an acute one, the controller is the last thing you should suspect and modifying it’s setting without good reason is detrimental to solving the real issue.

Couldn’t read through the list of configuration values to see what you changed. Tell us what you changed so we can look at before and after values… Whatever it was you changed, put it back.

I guess it’s possible that you purchased the ‘gremlin’ option with your machine. :crazy_face:


As soon as you have a failure, give it all a good visual check, including the mechanics. These machines are quite simple in operation, but sometimes cranky about how they are setup. If all the mechanics look ok, the only other item is the optics. Aligned and clean.

If the mechanics work and the beam is aligned properly, they work.

Your description would make me think you have some loose hardware, that was the cause of the alignment issue. Maybe elsewhere also?


No idea, how can I find out [what controller]?

You had to set this up.? You need to know what controller to setup Lightburn.

Look into your electronics cabinet on your machine. All the connections from your communications will be wired to it. It’s probably a dsp, which is why there is not $$ values. My electronics cabinet.

Here’s my controller. It’s a common Ruida 6442g. Yours probably looks similar. The cables on the right are the communications cables, the USB is disconnected…


Do you have a mA meter on the machine?

Are you sure about the alignment?

Good luck

:smile_cat:

Again, this machine is for work, which I just started less than a year ago. Apparently, they ordered this machine and another 2 or 3 years ago and no one has bothered setting them up. Since I used the old style pantographs in the navy a hundred years ago, I volunteered to set this one up. I got it working about 2 months ago, but it was delivered in 2019.

I changed cut parameters:
Idle speed from 300 to 131
Idle acceleration from 2,000 to 1,500
Max acceleration from 2,000 to 1,500
Speed factor % from 40 to 80

I changed engraving parameters:
x acceleration from 50,000 to 1,500
y acceleration from 2,000 to 1,500

I changed rotary parameters (not using rotary):
Pulses per rotation from 14,285.710 to 10,000
Diameter from 37.999 to 100

I changed miscellaneous:
Focus Distance from 5.9 to 0

That’s a good thought. I’ll go through the machine tomorrow looking for loose connections.

Same as yours: RDC6442S-B (EC). I didn’t see any loose connections in here.

Not yet, should I?

I was yesterday, but I’m willing to check it again tomorrow.

You should restore the controller to it’s original configuration. It’s an easy fix, if you saved the original settings via the ‘save’ in the machine settings you can just ‘load’ it and ‘write’ it back to the controller… Good habit to get into with these machines.


Doubt this is an issue, but many have found everything looks good, but the wire is loose in the connector. I ‘gently’ tug on the wire that I think may be an issue to ensure they are connected… Just a thought.


A mA meter is really useful as it gives you an idea of how ‘hard’ you are driving the tube. They are generally just a 30mA meter on the cathode (ground) side of the tube.

When it lases, it lases at 100% drawing whatever the lps can deliver. There is no 50% lase, it’s on or off. I checked my lps and found that at 50% power I get a reading of 14mA, that translates to 28mA at 100%. My tube is rated at 21mA. I turned the lps down so that max power is 10.5mA. It also fits my Lightburn percentage of power.

I’d suggest a meter and an adjustment of the lps.


I suggest you check alignment again and especially the output beam of the tube at m1 (mirror 1).

The tube needs to resonate properly to create the beam. A light burn mark (not a hole) at m1 will show you how it’s resonating. This can be an early sign of tube failure…

This thread is similar and shows his m1 burn…

Good luck

:smile_cat:

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