K40 laser not firing/used to work

Hi,
I’ve read the other posts on here and they don’t quite match mine.

My laser isn’t firing. It used to, now it’s not. It works when I press the test button, and the laser head moves when I send a print.

I’ve tried just using a new file and drawing a shape, no.

Background:
Started in July~ with a windows laptop. I’m a Mac user but I keep that POS around for machine uses. I seem to recall that it had the same problem on Windows computer, after updating, and then I researched and did some Gcode tinkering and got it working again, or maybe I reinstalled Lightburn. I’ll go try that.

Windows laptop died/dead/“preparing to repair” now I’m using Mac laptop.

This is from OMtech and I haven’t changed anything other than the update.

Where do we begin?

Check the S Value max to ensure it’s the same as the $30 variable in grbl. The default is 1000, I believe…


Ensure none of your protection systems, such as coolant flow and door ajar are suppressing the lps from firing.

Do you have and can you drive a voltmeter?

:smile_cat:

$30 matched in grbl at 1000. No voltmeter on hand. There’s fresh water in the bucket, door is closed, I don’t see any alerts

pump running?


Without some way to measure voltage on a few signals, I don’t know I can help you…

Sorry… :crying_cat_face:

:smile_cat:

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