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I'm collecting ideas on this topic.

I'm using a DIY alcohol stove made of a soda can. I have seen a guy refilling the same stove using this, but he doesn't explain where he found it, or how he built it:

enter image description here

  • what metal does it use for the tip (it should resist oxidation)?
  • how did he seal the metal tube with the plastic one (the sealing should be heat resistant)?

Optional: I use 500ml coca cola bottle to store the alcohol (small and super resistant). A cheap/light solution that would work with that would be perfect.

Don't hesitate to share your trick and ideas here!

EDIT: the question isn't "is it dangerous?", but "how do you do it?"

  • 3
    I am upvoting the question, because I am glad you asked, before trying it and hurting anyone. – James Jenkins Dec 31 '18 at 15:24
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    Why do you want to know how to do it? Is there any legit need for this? – Jasper Dec 31 '18 at 17:30
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    That guy is cutting toward his hand while making it. Also ill-advised. Does not seem very safety concerned overall. – jpmc26 Jan 1 at 1:42
  • Is this ethanol (commonly called alcohol) or methanol? There's quite a difference in flammability. – user15958 Jan 3 at 8:04
  • I have built one of Tetkoba's stoves and to make one of his foldable pot stands, I ordered 60cm of brass piping that's used for gas lines in RC models. It's most certainly the same pipe used here. I won't comment on the safety of the contraption. – Gabriel C. Jan 17 at 22:10
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I'm going with "it's too dangerous, so don't do it". I have two manufactured alcohol stoves, and both contain warnings against refill while hot.

That being said, my answer is "You don't".

Pictured (I can't see the video) suggests a squeeze bottle with a plastic tube running into a reservoir where the alcohol is supposed to be while flames are clearly showing.

My first concern would be the squeeze bottle. Although a flame requires heat, fuel, and air, a flame is not likely to go up through the tube and into the squeeze bottle, ready to ignite, since there is no air in the tube, and cold(er) fuel is being pushed out of the tube. Also, liquid fuel doesn't really burn - its vapors burn. So, there's nothing flammable in the tube.

Or is there?

What happens at the moment you decide you've added enough fuel?

You can keep the same squeeze pressure so that there is zero net pressure on the squeeze bottle: no positive pressure which would push more alcohol out of the tube; or negative pressure which would suck in alcohol from the stove or flaming vapors abouve the fuel line. Probably, nothing would happen, except the end of the tube - having passed through the flames - would also ignite. What's your plan to put this out safely?

You can apply positive pressure on the squeeze bottle, ensuring nothing gets sucked back; but now you have a stream of flammable (and flaming) fuel at the end of the squeeze bottle. Also, if you apply too much positive pressure on the bottle, you can potentially create bubbling in the reservoir of alcohol, and those bubbles could exit the stove creating a severe fire hazard around you.

You can also apply negative pressure on the squeeze bottle, but this seems more dangerous: the outside of the tube has flames, and now, you're sucking in vapor and flames into the tube and, subsequently, the bottle. Potentially more dangerous is supplying too much negative pressure, and siphoning all the (hot) alcohol from the reservoir back into the bottle.

There doesn't seem to be any safe way out of this, as all options lead to a flaming tip. Even if you decided one method was safer than the others, there's no guarantee you could maintain that every time, nor could you guarantee everyone could do it. Perhaps, you have a specialized steel filter placed inside the tube; this absorbs heat and prevents blow-back into the bottle with errant negative squeeze. Nevertheless, you have a tip of flaming alcohol at the end of the tube, and this is inherently dangerous.

Bottom line is that with any method you choose to fill up, per the photo, it would require delicate dexterity to maintain the precise amount of pressure on the bottle to not cause accidents.

One possibility is to have an external reservoir available outside the stove proper. A sort of "L" pipe which leads to the bottom of the reservoir, and the other end with a funnel shaped end leads sufficiently away from the stove apparatus as to not allow the vapors to ignite, and allows to pour fuel into the funnel. The problem with this is that in pouring, you create more vapors that could be ignited; and if the stove were nearly out of fuel (instead of just a little bit out of fuel), the vapors in the tube and funnel are now flammable.

So an external pipe assembly does not make much sense. Besides, it's probably going to be cumbersome to use.

All of this work - and danger - seems overpriced compared to a simpler solution: put the stove out, refill, and relight. It's not like a pressurized canister, so it's should be easy to accommodate.

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    I agree with your conclusion, but sucking vapour + fumes into the tube isn't an issue if you don't also suck in oxygen. – Chris H Dec 31 '18 at 19:09
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    @ChrisH If there is flame there is oxygen, and any empty space in that bottle is going to have oxygen. – James Jenkins Jan 1 at 10:00
  • Empty space in the bottle will not have oxygen. The space will be entirely filled with alcohol vapor (which will not ignite, too rich) unless you suck oxygen back into it. – Jimmy Fix-it Jan 13 at 17:17
  • Once you positively squeeze, then release, what comes back into the canister is air, not vapor. Thus, there can be air in the canister. And still, this technique relies on skill to not dribble alcohol, over squeeze, or suck in too much air, vapor, or hot alcohol. There is nothing safe about doing this. Every manufacturer will tell not only to not refill a lit stove, but to ensure that the stove is cool. Maybe lawyers doing a bit of CYA, but there's a reason they tell not to play with the stove. It takes little time or effort to refill a cold stove. – Andrew Jennings Jan 14 at 14:25
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You don't, adding liquid fuel to stove with a live flame is never recommended.

Related meta post Do we want a post notice for questions where people are using equipment in ways that are clearly incorrect or dangerous?

Believing the stove to be out of fuel, she tried to pour more denatured alcohol into it from a large container that exploded, shooting burning fluid and flames onto her daughter.

“We recreated the accident conditions in a ‘fire lab’ and the results were scary to say the least,” Barrett said. “The most dangerous aspect of denatured alcohol is that you can’t see it burning if you are in daylight conditions. In fact, my client and the rest of her group did not know why she was getting burned for a few seconds because they could not see any flames on her. It was not until the flames from her shirt burning became visible, that they realized that she was ‘on fire.’”

Source; Concord attorney warns of danger of denatured alcohhol

  • If you watch the video, the point of the contraption in the picture is to refill while the stove is working and looks like it does work – Reinstate Monica Dec 31 '18 at 15:34
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    @CharlieBrumbaugh :) there are lots of videos where lots of unsafe practices work. That does not make them good practices. – James Jenkins Dec 31 '18 at 15:39
  • That accident was the result of a different type of container than the one pictured. Yes refilling a stove from a large container would be dangerous, but that's not what's in the videos – Reinstate Monica Dec 31 '18 at 16:01
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    @Charlie the fact someone did it once doesn't mean this isn't dangerous. I saw a circus show last week with someone juggling knifes and lit torches. Doesn't mean I want to start doing it because it's "safe". Same thing here :/ It's extremely unsafe and has a risk of failure that would be catastrophic.... – Patrice Jan 1 at 14:44
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This is dangerous

And the most dangerous thing about it - is that it gives the appearance of not being dangerous. Don't refill a lit alcohol stove without being aware that it could become a fireball that will consume your facial hair, your tent, your skin, your travel mates and/or your/their visual acuity for perhaps life.

Sure. It might work once. Or twice. But it will fail, and when it does, it will be spectacular because you will be feeling comfortable beside your dog, inside your tent, with an open and full bottle of alcohol in your hand and in the next second you won't be none of those.

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I understand that you may want to do this if it is really cold out and or the fuel is really cold. It would allow you to keep the flame burning without risk of not being able to relight it, because of temp or some other environmental condition. To answer your question without berating you about safety.

  • The bottle does not matter as long as it is not dissovlable by the contents, you could use a ketchup dispenser.
  • The tube is brass or copper
  • The fit is friction fit

Good luck and enjoy the outdoors.

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