Laser is engraving well, can’t figure out why it won’t cut through 3mm ply

Hi!
I finally got my laser up and running and I’m just figuring out how to use it. I’ve been running some test cuts, and it’s engraving well. But it won’t cut all the way through 3mm ply.
Now I’m running a 50w C02 laser, so I should have lots of power. I’m guessing I’ve got some settings wrong in Lightburn
The bottom box was run 2 passé at 20mm/s at 70% power and it barley catches a fingernail

Do you have a mA meter installed in your laser? It would be helpful to know how many mA your tube is using at 70% power. Also could you post a screen shot of your lightBurn settings and a picture of your control panel on the laser (I am unsure if you have a current limiting pot or not) A 50W laser should be able to cut 3mm plywood at about 10mm/s using 1 pass if everything is set up correctly and the mirrors and lens are clean and aligned correctly.

Hopefully these photos work!
That’s my settings, and the ma reading while cutting

OK, the digital panel readout is not 8.1mA, it is 8.1% of the total amount of power the laser power supply (LPSU) is capable of outputting. If I had to guess (and without an analog mA meter to show it, I am just guessing) that power level is only about 5mA and then lightburn is saying to use just 70% of that, so it would explain why it is not cutting, that is set to a very low power. I would up the front panel number to 50%, and try again. Be careful not to exceed that 50 by much, you risk over driving the tube (It should never use more than 20 - 22 mA of current. I strongly suggest installing a mA meter so you can set and forget the maximum current on the front panel, then just adjust the power using LightBurn after that. C3D sells the correct mA meter and has an installation article to walk you through the install.

That’s got it sorted! Thanks so much!
I’ll def consider getting a mA readout, I’m massively new to this. Still figuring out the ropes

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You really need the ma Meter to know if you are overdriving your tube. My experience is that the digital display is not a reliable indication of how much power is being applied. I hit 15 ma when I enter 28.1 on the display. So don’t operate too many times before adding the ma meter.