Laser seems to have lost power

can not cut 3mmm plywood, was able too at first. checked mirrors for alignment, and cleaned same. showing 15 Ma on meter in line mode. but no penetration even in thin cardboard. do I need a new tube? Raster seems to be ok.

Chip, what speed are you cutting at?

Have you focused your lens the proper distance from the material?

Can you try cutting paper, then cardboard, then wood? (You may need to adjust speed and power, obviously.)

What has changed on the machine since you could last cut wood?

Running at 50% power and 5 mm/sec focused at 50 mm. Was able to cut card board last night, but not 3mm birch plywood. Am continuing working on focus distance, hoping to find sweet spot. Have a manual lab stand to adjust z, will attempt to do in small steps. using dial verniers for distance. .Only thing changed was took lens out to clean.

Chip, look up “laser ramp test” for a method of testing where your laser properly focuses the the beam the most powerful. It’s basically running a cut on an angled piece of material and then examining the cut. It’s worked well for me in the past.

Did ramp test, add proved it was within focus rage, still not able to cut 3mm ply. tuned lens back to original direction which was flat side up. And ran with convex down and saw no difference in beam width or cutting power.

You’ll definitely want the flat side down/convex side up for your lens to focus properly. Make sure you’ve properly seated the lens as well when putting it back in place.

If you’ve got your mirrors and lens clean and aligned, and your mA meter is showing 15mA output, and you’ve got proper focus, it should cut properly. (Is it still doing raster engraving properly?)

I’d suggest you methodically go through everything again, and make sure you haven’t missed anything.

If raster works, maybe the power is low in your G code/LightBurn cutting setting.