Vacuum tray replacement for cutting lightweight materials

This is possibly the most flattering comparison anyone’s ever made to me.

The idea of a vacuum table and or modifying the tray has been floated here in the far past. I can’t recall if I got the idea from my own daydreams or from reading about it… it’s not the biggest leap, logically. That being said I’ll take some credit, I think my design has a few good tricks.

I can already see ways I could improve it —mostly around ease of assembly, not actual function— but it was a bit of a process to cut and build so I’m not likely to iterate unless I think of a way to make it work better. So far it works perfectly so no complaints there.

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Wonderful invention! Do you have any thoughts of posting a supply list? Or even better, instructions? Or you could put it all together in a pdf and sell on Etsy, I’m sure there would be tons of interest.

Just one correction: Seklema mats are not at all sticky. They just have some kind of grippy magic that makes some (but not all) paper stick.

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Seems like a great idea for a Glowforge upgrade tray. Like the upgradable print head.

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I am wondering if it was worth it to buy a second crumb tray and modify the first as there is plenty of room for fans in the back facing up (even sticking up 1/2 inch) and the stainless screening on the old grid or replacing it.

I really miss living near Skycraft, This is exactly the sort of project you could walk in cold and find everything you needed including the crumb tray sized steel box, screen, fans, fasteners, power connectors, and LED lighting to tell you it was working, plus a hundred dollars of stuff you didn’t know you needed all for the same price as Amazon without the extra stuff.

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You’d need to modify it a lot, the gap in the front is a killer.

As for “worth it”, this cost me about 35 bucks all in, with the fan and screen costing about 30 of it. Crumb tray is $130 I think. So you’ll pay about 4x as much just for the tray, then buy a fan, then have to hack it up with zero error margin (opposed to cutting new parts if your home built design has issues) and still have to solve several engineering problems that aren’t too easy to solve for.

In hindsight making it from scratch was a no brainer.

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Loved the idea just not sure if that doesn’t affect the fume to be extracted from the main extractor of the machine!

Good idea tho ! I’ve made a simple solution which I’m using since then… just a pc of acrylic that I pass on a specific glue and let it dry, it is working for around 1 and a half year!

Which can be seen here!

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It does, a bit. I mean it blows air around a bit inside the machine.

That being said, paper just isn’t that much material, so it doesn’t make a great deal of smoke in the first place. Even with the regular crumb tray you almost can’t even notice any smoke with something like tissue paper, there’s just not a lot of paper being lasered.

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Two of my very favorite things combined, GF hacks and paper cutting!

Brilliant. I’m already obsessed. How did you hold out so long?

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I’m hopelessly enthralled, and Amazon is my enabler. The parts are already on their way.

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Oh how I wish I had the knowledge and skills to do this.
Brilliant!!!
Thanks for sharing. <3

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Ingenious. To piggyback one step further on @cynd11’s comment (Etsy pattern) - I know there would be buyers if you made and sold the whole unit :grinning:

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Its a fair amount of labor, I’d have to charge hundreds of dollars to make it worth my time… and I still wouldn’t like doing it, especially the shipping process :slight_smile:

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another thought would be if you had a fan that could be USB powered, all you need is a power bank for charging phones. easily rechargeable and usually pretty compact.

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CFM in 40mm 5v fans is pretty abyssmal from what I saw. 12v seemed to be the price of admission. whatever you get you’re fighting the air assist fan, which is fairly powerful.

Like I said earlier ideally we’d optimize for a mix of static pressure and cfm ratings, but finding static pressure data for these fans is not easy, so cfm’s all I got.

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This is brilliant.

Thank you for the detailed writeup. This is a mod I could seriously get behind.

I am excited just thinking about the possibilities with paper.

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Fantastic idea. I have the basic GF but I installed an external fan. If you didn’t want to tap into the power inside the GF you could run AC into the box using the built in fan exhaust port. Since I don’t use the built in fan when using the external fan you do t need to worry about the AC cord interfering with the built in fan. There is a setting in the software where you tell it you have an external fan which turns off the built in internal fan.

Also an external fan is SO MUCH quieter. I had to put an indicator light on the external fan controller so I’d remember to turn it off. It is that quiet.

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I really love this and feel like I need one! I also like the idea of using my removed exhaust fan and power connection.

First thoughts:
I might not feel the need to go full size.

Do you get any scorching on the bottom as the laser goes through the work and screen?

Also is flashback an issue with the screen you chose?

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I thought that too but quickly realized That it takes almost no additional effort to make a full size one versus a partial bed, and that you don’t need to add additional fan capacity, since downforce is related to the surface area of your piece. In the end a full-size bed was the way to go for me, my smaller test was a good proof of concept but I wanted bigger.

Yeah, this is a long-term concern. I do have a few light marks on the bottom from my tests, it all comes down to how much power you’re putting into your cuts. I may line the bottom with aluminum foil to prevent that. The way I designed it the mesh screen lifts off, it’s not attached. It allows me to have access to the internals.

It’s a stainless mesh, so it’s about on par with the crumb tray. It just has a different pattern. Standard techniques can be used to mitigate flashback, proper settings and or a layer of masking on the underside of your peace will solve that problem more or less.

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Outstanding!

I have used some of the commercial laser cutters with their vacuum table options and, had wondered about something like this around the time I got my Glowforge.

I like that the Seklema mats mostly stop any flashback but, as you note, it is probably manageable. Clean up for myriad tiny bits of paper would certainly be easier. With the Seklemas, I use the small shop vac in one hand and a scraper in the other.

I think you hit it out of the park here. Thank you for sharing.

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I’ve had better luck adjusting the adhesion down with a t-shirt than with a towel.

I use the spray stuff intended for temporarily holding t-shirts while printing, which may be relevant.

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