As the title states, I can not get my laser to reduce power to zero.
I was trying a grayscale gradient and the laser was unable to reproduce it. It burned the material even where it was white.
So I tried a test burn at zero percent power and the laser still burned the material.
I am missing something?
I believe you need to check if the parameter $32=1.
I also believe you need to check in “Device Settings” > “Basic Settings” if the “S-Value max” field is set to 1000.
In the “Console” window, type $$, press “enter”, copy and paste all the text obtained here.
Fiber is a different dragon, and I do not have one.
Go in to Machine settings and look for something related to both minimum power and minimum speed. A Fiber user will jump in and assist as soon as they spot this posting.
I kinda was thinking that as well. There is no input option in the console window.
Doesn’t look like there is a minimum setting for power.
That is the Device Settings window. Does your LB have a Machine Settings one too?
No Mike. There is no Machine Settings window. Just the standard Settings window.
Makes me wonder if you can change any of the machine operating parameters…
I found this on another thread.
Fiber lasers do not have machine settings - Those are “settings that live in the machine itself”, and fiber lasers have no such thing. All settings are in the Device Settings within LightBurn, which stores them as part of your LightBurn preferences and applies them to the machine every time it connects or runs a job.
Hopefully someone with some fiber laser experience can tell me what’s going on.
Maybe @jkwilborn can help. I think he has one of those.
Is this a new machine or one that you’ve had and used?
There isn’t much that is user accessible, besides the device settings. These may reside in the controller, but I think when you change devices or start the software up, it reloads them.
The only thing I know of to look at is the source type, is what’s in red correct? This is the device settings → ports and laser settings tab. If this has worked previously, then this isn’t likely to be the issue.
If it hasn’t I’d make sure and contact the vendor asap.
Good luck.
Thanks for the info Jack.
I sent an email to Commarker support. I’ll let you know how it goes.
Forgot to ask if you loaded the supplied configuration file into Lightburn? This is where this information originates.
If you’re referring to the “.cor” file, yes I did. You can see that in the image grab of the device settings I posted earlier.
The laser has worked fine on projects I’ve done over the year I’ve owned it but this is the first time I attempted etching an image. Until then I never knew this issue existed.
Thanks for your help Jack. I’ll post again after (or if) I hear back from Commarker.
I’m referring to the configuration file, not the lens correction file. You enter it here at least for my machine. It should be pre-packaged with your machine. On mine, it’s called markcfg7
Have you tried one of your previous jobs that worked?
Good luck.
When I read that, I thought, Fiber what?!!!
Then I read the “Subject” and thought, where the hell is my head? I can’t be that out of my mind.
So I checked the user data and found: “Firmware / driver”: GRBL 1.1h
That saved me a trip to the doctor!
What happened is that, not knowing the machine, I went looking for information in the user data, which apparently wasn’t up to date.
@SlowPaddle
Don’t pay any attention to what I said; it doesn’t apply to the machine discussed in this thread.
And I apologize for the misinformation.
Yes, I did do that when I first set up the laser.
Here’s what I got back from Commarker.
Based on your description, the laser actually has a “minimum output power” protection (usually 1%–10%). If the software is set below this value, the laser may automatically maintain output at the minimum level, which is normal.
Additionally, LightBurn engraving of grayscale images is typically used for 3D reliefs. Based on our experience, you usually need to engrave around 300 layers, which takes approximately 3–5 hours to achieve a visible effect.
Best regards,
Commarker Support Team
Seems there is no zero percent power. Not what I expected but I’ll live with it.
Thanks for all the help!
The tube is full of gas that must ionize to lase. The voltage must reach a certain voltage to glow, just like a neon bulb. Once lit up, it must have a minimum current to maintain ionization. Drop below that current and the light goes out.
If you want zero (actually about 0.2%) to 100% power range, you will need a diode laser.
Fiber lasers don’t use a tube with gas in it.
From Google: The light in a fiber laser is created by semiconductor laser diodes.
Sounds like you’re thinking of a CO2 laser.
Can I blame memory loss on my age? You are right! 
I’m 67 so I fully understand. 
