Glowforge Burning / Yellowing Wood and Photo while trying to make Puzzle

Thanks @kanati - Makes sense, do you have a recommendation on speed maybe like 300 with 2 passes? Any idea why the exact same setting works in another glowforge? I’m wondering if theres something wrong with mine.

Your svg might be faulty. It’s hard to know but if the paths are overlapping it could cause significant overburn.

You can also seal it first and then wipe it off after.

You might be able to mask. @jbmanning5 had a great trick for masking puzzles, maybe he’ll appear with the link.


The lens I’m referring to is the one you need that blue removal tool for. If it’s in upside down you will get wide lines and lots of charring.

@beerfaced is it possible the lens is upside down when it was shipped to me? I think it came pre installed and all i did was attach it to the arm in the machine.

That would be me amazing!!! I think the SVG is fine because i made a friend try it on another glowforge and it was perfect. Shouldnt be any overlapping lines. But I would love to learn more about masking if you’re open to sharing your tips @jbmanning5 :slight_smile:

Hmm let’s see if I can search it down.


Might not work for your irregular pieces but there you go.


Is it possible I have a defective lens, theres a decent bit of scratches on mine and I have only had it for a few days.

It’s very easy to check. Pull it out and have a look.
Oops, I see you already did that.

Have you tried cleaning it with a zeiss wipe?

@beerfaced - I have it seems to be part of the lens itself? It only appears at a certain angle. Could this be the issue with the burning dots in my puzzle i wonder. Hmmm…

It’s highly unlikely to be related to the lens. The last photo in your post is probably the most indicative of the problem – notice how there is burning/scorching in both tight turns and almost straight lines?

If only the tight curves were burned, that would suggest a speed issue, but the fact that nodes along the straight(er) lines are also cooked could be an indication that the svg has a lot of nodes defined along each segment. I don’t know the command in Inkscape offhand, but there should be a way to “simplify paths,” reducing the number of nodes to the minimum needed for your design.

I may very well be 100% wrong, but that’s where I’d start.

Good luck!


Is your friend’s GF the same model as yours? (Pro, Plus or Basic) The Pros and the early Pluses have a higher powered tube so the power settings behave differently than the Basics.

Thanks @dwardio , its strange because I’ve tried the exact same SVG with another glowforge and works perfectly. Will give this a shot though, definitely good idea!

@ekla - Exact same model Pro, with exact same specs and material (down to the same printer) :frowning: . I’m not sure what it could be

That is weird then. Crumbtray perfectly flat, sitting in the divots evenly? Your lens does look funky but not in a way that should produce this pattern.

Longshot: I don’t think you mentioned if you were cutting the puzzle face up or face down? If face down the smudges could possibly be flashback. (put a sheet of copy paper between your crumbtray and the puzzle when cutting to minimize)

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@ekla - Great callout, this may be it. I do cut the puzzles face down with tape on the crumb tray. Do you think it would help to add an additional piece of paper to reduce flashback? Is this a potential fire risk?

Adding a piece of loose paper would be a fire risk, but fairly minimal as cutting things with a laser go. That could definitely be flashback on the puzzle though. Can you add masking to the piece before cutting it, or would that damage the picture?

Did your friend cut the puzzle face-down as well?

Several people have commented that they regularly use newspaper underneath the item they are cutting, including jigsaw puzzles.

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I’d try a small test with just a sheet of paper and no tape on the crumb tray.
I’ve been cutting the acrylic earsavers this way and get zero flashback. (Acrylic unmasked too)


Def looks like flashback to me.

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Firstly - THANK YOU so much everyone. This community is truly amazing!!!

So I think the issue was 100% flashback, even with paper i was getting similar issues :(. I used a level and wildly enough I believe the floor in my room where the glowforge was held was not level. I moved it to another room which is more level and not getting flashback anymore.

That being said, the last issue I am encountering is slight discoloration of the photo paper and or wood? That yellowing. Even with the change to ensure the flashback holes dont occur, im still receiving discoloration(see slight discoloration at speeds of 175 - top and 180 bottom at full power, 0.125 focal height for 1/8 inch wood).

I am also putting tape on crumb tray and photo side of wood face down.

Any ideas how to solve this last issue? See screenshot below

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