Rear pass-thru fire extinguisher

I could not make this, but I would surely love to buy it.

I was in that period before sleep that is the most creative. Thinking of a goal, having a solution, beating that solution up to find what is wrong with it, and changing the result, beating that solution up etc. At one point thinking of making the suggestion that Glowforge design in a place to hook up a CO2 bottle and a delivery system to use even on small flames that only a tiny amount of CO2 would be necessary to fill the entire chamber and douse any sort of fire ( @dan this is still a good suggestion to think about for the future designs!)

But of course, for those of us with a Glowforge Pro such a designed in concept is too late as we have no access point…Oh yeah, there is the pass-through slots with the removable shields! I notice that many folk who are using them are only using the front slot but we don’t want to eliminate the possibility of using the rear slot occasionally.

However, if there were a removable rear shield, that would still operate as a shield, but contain the capability to let in a cloud of CO2 via a 1/8 inch slot that would dead end and thus still act as a shield not much more CO2 than needed to fizz a bottle of soda would put out almost any fire and so could almost be a first solution even over a wet rag. With a car door opener as a means, you could be across the room and give it a touch and instantly have no more fire, Using the equipment already available to fizz soda bottles the expense of using it need not be great. Unless you were silly enough to try cutting magnesium in which case you would deserve to lose the Glowforge, I can see only a single slight problem of cold shock and only the company engineers could make that call.

How about it? Does anyone wish to pile on and say what a bad ides this is?


Neat idea.

One concern might be adiabatic expansion of a gas tends to yield a huge drop in temperature, and you’d be injecting right near the glass tube. Thermal shock could be a problem.

Someone posted about handheld halon fire extinguisher to keep nearby, it seemed like a good idea but was really expensive.

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I bought that Halon extinguisher. When it arrived I read all the instructions and left it in the box. Like not for residential use, not for spaces less than 700 cubic feet, if you inhale the gas resuscitation methods. I live alone and Glowforge is in a small mud room. So, it stays in the box and I keep wet rag nearby.

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Yeesh. That’s quite a warning.

The thermal shock could be bad. How about an oxygen proof hood of some sort? Choke out the fire.

Think of how much air flows through the machine while cutting. You’d need an oxygen proof room!


I thought about having the area under the intake fan as the CO2 fire suppression but it would nearly have to be built into the table.

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The wet rag or even spray adhesive on an absorbent wet paper towel made damp are considerations. Even Waterglass (sodium silicate) mixed with water. Aside from expensive I think the dangers of halon are nearly as much as the fire.

I thought that CO2 was a bad idea because it created an acidic cloud that hurts the GF and electronics. Might be easier to just stay observant.

CO2 by itself isn’t acidic. Mixed with water, you get carbonic acid, but I doubt it would be enough to damage anything. Maybe I’m wrong here, but I think CO2 wouldn’t have much of an adverse effect on anything, save for the temperature concerns.

I was thinking about that. My first thought was a direct copper line from CO2 button to a quarter inch by several inch copper rectangular opening sealed in back (perhaps painted) however if it first goes through several feet of copper line dumping much of the extreme temps on the way then what came out would still be very cold but not near as extreme. As for carbonic acid, it is a very weak acid when concentrated like in soda water, and like when you open a bottle of soda quickly goes back to CO2.

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Definitely do what you need to be safe.

A couple of thoughts about the Halon (I have one, btw). It’s not for minor flare-ups (nor is any other bottle extinguisher) – it’s a “save your house” device. Unless your mud room is air-tight and you’re not venting the GF to the outside(?), its unlikely that you would reach toxic levels unless you emptied the entire bottle then remained in the space (I’d run like heck at that point). Again, we each have our own comfort/safety levels – I’m not trying to talk you into anything you feel is unsafe!

We used these onboard navy ships specifically because you can breathe it for short periods and it doesn’t corrode electronics like Purple-K or, well, salt water. Of course, when you’re at sea with 5,000 of your closest friends, you can’t run away from a fire… :wink:


this. ^^

as dwardio says, you have to find your own comfort level, but my GF is in a room with a door and a window. as the extinguisher is an “OH SHIT” device, not an “doh” device, i have no doubt that i’d be ventilating the room immediately after putting out the fire.