Alcohol stove safety and questions

Posted by: Gershon

Alcohol stove safety and questions - 06/02/14 07:13 AM

Recently, I've been testing a Trangia alcohol stove. I've been using a SVEA 123R stove since 1977.

A couple weeks ago, I took the Trangia stove on a trip and used it in a shelter where it was dark enough to see the flame. Wow, that is pretty exciting. I wouldn't want to use it in a bright light where I couldn't see the flame.

I decided the windscreen wasn't tall enough, so this weekend I took a taller windscreen about three inches high. It boiled the water almost as quickly as the SVEA, and it worked well about 10 times. I was experimenting as well as drinking coffee and making meals. Then the windscreen melted and dumped the water.

It seems like the windscreen has to be designed for both the pot and the stove. It seems like the windscreen should surround the bottom 1/2 inch to inch of the pot. It seems like the pot should be about 3 inches above the stove for best efficiency.

Then there is the problem of removing the windscreen so the stove can be extinguished. I have a minor burn on a finger to show this isn't as easy as it sounds.

Does anyone have pictures of a design of a DIY windscreen that works well.

At this point, I consider an alcohol stove somewhat dangerous because the flame is invisible in bright light. I'm willing to be educated.

Thanks,

Gershon
Posted by: Rick_D

Re: Alcohol stove safety and questions - 06/02/14 01:22 PM

I'm a little confused--is your windscreen also the pot support?

FWIW my limited field experiments with the Trangia include a little folding tripod stand/pot holder, and an MSR foil windscreen (because it's handy). IIRC I used a 1.3L Evernew pan and lid, but that could have been different.

I extinguish the flame by shoving in the flappy disc of the flame-control top.

Completely agree the flame's invisibility is a big accident potential. Love the silence and lack of moving parts.

Cheers,
Posted by: Gershon

Re: Alcohol stove safety and questions - 06/02/14 02:17 PM

Originally Posted By Rick_D
I'm a little confused--is your windscreen also the pot support?

FWIW my limited field experiments with the Trangia include a little folding tripod stand/pot holder, and an MSR foil windscreen (because it's handy). IIRC I used a 1.3L Evernew pan and lid, but that could have been different.

I extinguish the flame by shoving in the flappy disc of the flame-control top.

Completely agree the flame's invisibility is a big accident potential. Love the silence and lack of moving parts.

Cheers,


The windscreen was my potholder. I only use a 2 cup pot, so it's not too heavy - that is until it melted. The design worked well until then. I had a backup stove, so it wasn't a problem.

I'm hoping someone has an efficient design that works in windy conditions.
Posted by: billstephenson

Re: Alcohol stove safety and questions - 06/02/14 06:08 PM

I made a windscreen for my super cat stove out of a disposable aluminum roasting pan formed into a tube. I'm sure you could make one that will work for the Trangia this way too.

You use two pieces of wire or even tent stakes to slide through your tube to hold your pot above the stove. Here's almost exactly what I did...



The difference is I cut the bottom out of the roasting pan, folded it lengthwise like a three panel brochure so it is three times as thick, and I made mine in one piece. The ends clasp together just like in this video.

My pot sits right on top of the super cat stove so I don't use the tent stakes to hold it above the stove like you would with the Trangia, but I'm sure you get the idea.
Posted by: Gershon

Re: Alcohol stove safety and questions - 06/02/14 06:14 PM

This us an excellent video. Thanks.
Posted by: orclwzrd

Re: Alcohol stove safety and questions - 06/02/14 11:35 PM

I use a whitebox stove and it comes with windscreen. once I boil the water and pour it into what ever, I can extinguish if needed the stove by inverting the pot over the stove. The windscreen is easily flipped away from the stove. Care is always necessary but practice yields better and better results!

john
Posted by: Gershon

Re: Alcohol stove safety and questions - 06/04/14 06:17 AM

Bill,

I made a windscreen like the one in the video and it works well. I think it would work better if the pot was a little higher and the windscreen was taller so it would wrap around the sides of the pot. There is too much heat lost up the sides.

Thanks for the idea.

Gershon
Posted by: billstephenson

Re: Alcohol stove safety and questions - 06/04/14 12:19 PM

The one I made is a bit taller than that shown in the video.

The aluminum from a roasting pan is very easy to work with and very light. I prefer it by far to steel.

You can form it into a cone shape if that would work better for you, and you don't need to fold it double or triple. I took another look at mine and all you need to do to give it some strength is to fold it over about 1/2" along the top and bottom sides (i.e., double the wall thickness along the edges).

Being an old metal man I should probably make a video myself. That kid did a great job, but I probably know a few tricks that could make it easier. I need to get some batteries for my camera frown
Posted by: Gershon

Re: Alcohol stove safety and questions - 06/05/14 09:39 AM

Orclwzrd,

A friend of mine who has tested many stoves said the white box stove is the best of all of them. It will boil water faster than anything else.

Bill,

My first draft was just like the video without the holes in the top. I tried adding a sleeve to make it taller, but it didn't affect the fuel consumption although it boiled a little faster.

My meals are heat and eat in an aluminum cup. I let things soak for awhile to rehydrate. This morning, I made oatmeal in windy conditions and it worked perfectly. Unfortunately, I didn't measure how many grams of alcohol were used. I'll do that tomorrow.

When I was done, the top was cool enough to take off with my hands and the cup handle was almost cool enough to lift the pot off with my hands.

When I'm done, I can unhook the ends of the windscreen and it slides into the cup for easy storage.

There are probably ways to make the system more efficient, but it hardly seems worth the effort.

I did learn the system has to be designed for the pot and the person's style of eating.

Keep in mind, alcohol stoves are prohibited where there is a fire ban. I don't agree with that policy, as the Trangia with this windscreen is safer than the SVEA.



Posted by: Gershon

Re: Alcohol stove safety and questions - 06/13/14 08:43 AM

After testing the Trangia stove with the homemade windscreen, it turned out the first draft of a windscreen worked the best.

Here is a video of me using it.

[video:youtube]http://youtu.be/Ikb_eo1OVQ4[/video]
Posted by: 4evrplan

Re: Alcohol stove safety and questions - 06/13/14 11:13 AM

Gershon, you'd think I'd get tired of watching alcohol stove videos, but I never seem to. Thanks for posting.

I wasn't really looking to change my stove, but I was sitting at my desk the other day drinking a v8, and the thought popped into my head, "You know, I think I've seen instructions online somewhere for making a stove out of v8 sized cans." So I threw one together and tested it out last night. I had it on a metal pan on top of my kitchen stove, and it worked really well, but it was so small that it's a bit unstable. My test pot had a heavy handle, so I had to put it way off center to keep it balanced. I didn't have water in it, because I was really just testing to make sure it would stay lit and burn cleanly with the pot covering the top (it did), and I was planning to take it off after a few seconds. When I lifted the pot off, however, the stove stuck to the bottom for a split second, and when it fell, it turned over and spilled the fuel into the pan. Thank goodness it all landed in the pan and not over the side. I really should have been testing outside.

I guess the point is, you definitely have to be careful with these things.
Posted by: Gershon

Re: Alcohol stove safety and questions - 06/13/14 01:06 PM

4evrplan,

If you made a video the house would have burned down. Once I realized nothing bad happened, I read your post several times and laughed all the way through it.

The first alcohol stove I made was when I was a kid. I put a beaker about half full of alcohol above a bunsen burner. The beaker had a cork and a piece of copper tubing sticking out the top. It shot out a flame a couple feet long. Needless to say, it could boil water quickly. It would also melt glass if you held it in the flame.

Seriously, experiment outside where you can't burn anything important down. It is best to experiment when it's a little dark so you can see the flame.

Oh, be sure you don't have any alcohol on your hands when you light the stove. It hurts when you catch your hand on fire and don't see the flame in the sunlight. Don't ask how I know that. Besides, you might knock over your beer while waving your hand to get the fire to go out. Of course, that just makes the flame hotter.
Posted by: billstephenson

Re: Alcohol stove safety and questions - 06/13/14 02:13 PM

Both of those post had me cracking up laugh

I read about the sticking problem when making my SuperCat stove and had it happened while testing it too. In actual use it's really not a problem though.

The SuperCat stove will boil 2 cups of water in cold weather with the amount of fuel it holds, and it cools off almost instantly when the flame goes out. So I just use care when setting it up and don't mess with it once I've started it.

As a 3rd generation metal man I grew up using torches and welders so flames and sparks were a part of life. You do learn a bit about dealing with the consequences of being unaware or careless and sometimes those lessons get learned the hard way.

But even experience doesn't make you immune. You learn that too. I was working with an old timer once and I'd just hammered out some steel that'd I'd gotten red hot. Just after it turned black he came over to check on my work and before I could utter a sound he picked it up. I saw the smoke rise from his callous and sizzling old hand and had to ask the standard smartassed question, "Was that hot?". Generally that would get you an instant insult but he just looked at me and calmly said, "Naw, I just didn't need to look at it for very long" and walked away.

I've long forgotten all the insults I solicited, or showered others with in response, but I'll never forget that. laugh