Standing on the shoulders of giants

I merged frostyspeed ’s amazing crumb tray removal jigs,

with jdanramey ’s awesome no crumb tray set up jig

(and modified the size to fit my 1/8 in baltic birch from plywood Hawai`i)

To make…

If either of you dislike the merger and would like me to take this down please tell me. They are both essential tools for the Glowforge, and should be part of the paid how-to video guide.

jig7.pdf (475.5 KB)

hmm svg was corrupted, that sometimes happens, not sure why.


I am curious if the use of tools like this reduced flash back and need for masking on the back side of material. I assume that these are used in a fashion where 4 of them are put in the corners and the middle of the material is unsupported. If this is that case, perhaps, most of the time with cutting, the laser would go all the way through and hit the bottom of the Glowforge. If this is the case, and the material is still high enough, could this significantly reduce flashback?

If I’m understanding their use correctly, you need material that doesn’t sag where it is not supported, especially after any scoring and cutting. If you’re trying to avoid flashback, a set of painter’s pyramids would seem to be a better solution for many materials.

I wouldn’t use this for cutting through things, moreover something that is too thick to fit in the focal point of the lens for engraving. Such as a thin cutting board that you engraved “congratulations on your marriage”, and the laser was too defocused, and it engraved everything a little bit too wide, but you ended up giving the

gift anyway because you didn’t know any better.


Max Headroom. Nice.


Hey, this just popped up below another thread in “suggested” - I have started to prop up material above the tray to avoid having to mask the back side of it. I just use a couple of rules I have from PG Med material, scraps, whatever I need to support it where needed. 1/8" above the bed is enough to eliminate flashback for the materials I use most. Try it out.

Obviously you need to ensure your focus height is correct.


I need to start doing that. Or just place tie dow pins all over the crumb tray, and make longer tiedown pins for the wood hold.


I have thought of this often and tried it on and off with mixes success. I think it is worth further discussion as I can see this saving tons of tape and other material used solely for controlling the ravages of flashback. I can already, for the most part, score and engrave with no need for masking. Even during cutting, the topside is, for all practical purposes fine. I think what I have been missing to perfect the bottom is making sure the focus is good. The set focus should take care of this though. I need to re-look at the issue.

You can also throw a piece of paper underneath, but - for me - why waste paper.

Focus on the surface for “Medium” (3mm/1/8") material is good, but for thicker material, I have found experimenting with different focus heights can give you very different results. I am testing different materials and will post a thread on this when I have finished.

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