Glowforge not cutting through at settings it normally does?

Hey all,

I recently have run into a snag where my forge isn’t cutting all the way through boards it previously would have.

For context, I’m cutting .25" cherry plywood boards with the settings of
Material thickness: .25"
Speed: 145
Power: Full.

Normally, like up until yesterday, it had no problem cutting through these boards, but as of today it’s suddenly not. I’m not sure what I’m doing wrong or what has changed.

Any thoughts/tips/suggestions?


Not sure how long you’ve been at this so apologies if any of this is too basic but check out #5:


.25" is right at the limit of what the GF can handle, so any slight variations in material density could cause problems.

Change your settings, slow it down a little, see if that helps. That’s pretty much all you can do, as (again) 1/4" is really pushing the limits of this machine.


It looks like my everything needed cleaning. I’ve been cutting a lot of plywood recently so I’m not super surprised but I guess I underestimated the amount of dust buildup it was causing.

Thank you!


It’s very important to keep the optics clean. Infrared is just another wavelength of light - until it touches something, then it’s heat. Accumulation on the optics gives the light something to deposit its energy on and will eventually burn them. I check mine every time I start it.
The window under the left side gets dirty first, then the window on the side of the head. I probably clean those two 10-15 times before the mirror and lens might need it, of course, it depends on what material you are using, some are dirtier than others.


Agreed on frequency.

I also wipe the lid camera every time I clean the windows.


Yep, check your lenses and clean them often.

See also: Lens Fail: Burnt O-Ring; Not Cutting Through Material - #3 by Stu
in case you have something florked in the lens housing.


Yes! I had forgotten that.


I often overlook cleaning the optics as a possible cause. It takes just a few seconds so I rarely even think about it.


I clean off the laser tube itself (with a baby wipe/moist towelette) - not because it needs it, but it getting dusty is a reliable indicator that the rest of the machine needs an optic cleaning with a Zeiss wipe :slight_smile:


You didn’t mention whether you were using PG ply or other brand. Most plywood that is not PG will give you lots of problems because of excess glue and/or voids.


I’m not actually sure if my plywood is PG or not, but i’ve cut dozens of things out of the same boards.


“PG” is shorthand for proofgrade, so it’s only PG if you’re buying it from Glowforge.


Ahh, good to know. Basically none of the sheets I cut are proofgrade, but plywood bought usually off etsy for glowforge use that I think mask myself.


That’s the problem with 3rd party material, you never know if you are going to hit glue or voids because it is rarely engineered specifically for laser cutting.


Okay all, all the optics are clean, I bought and installed a brand new lens, the mirror is clean, and its now not cutting PG materials at normal settings. What gives?

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Given your join date of 2019, it’s possible your tube has run its course and is failing/failed. Or the power supply.
If a “Gift of Good Measure” won’t cut properly in the top left(shortest possible laser beam distance - and least effected by beam alignment) , on Proofgrade, either something has gone horrifically wrong with the alignment or you aren’t getting the power you’re supposed to.

They’ve rated the tubes to two years. Anything after that is bonus.

Have you talked to the support team at Glowforge via the support page yet?
They’re about the only ones who could deep dive more.


This is something I have deeply feared. I will check in with the support team :frowning:
I will try the gift of good measure later today.

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I edited to add, on proofgrade material. Support will ask you to do it anyway so take pictures to include to try and move past that step with them.


" .25" is right at the limit of what the GF can handle, so any slight variations in material density could cause problems."

thats such a bummer that this is the case as I spent the first 8 months of owning my GF cutting CLEANLY through 1/2" maple, then there was an update and now 1/4" is sometimes tough.

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