A better soda can stove
Back in the early days of New France, a coureur des bois would spend a little fortune for his ultra light birch bark canoe. Space era materials now abound in consumer products. The modern backpacker will also find many opportunities to trade a large amount of money for light gears. Every gram count. Tents have carbon fiber frames, fork and spoon are merged into titanium sporks, white leds provide dependable light sources, Gore-Tex and microfiber enable light, warm, waterproof cloths. The outdoorsman value light gears. It's part of his nature. It's enough work to carry oneself over rough portage; who would want to carry a hard wood boat?
The modern outdoorsman have it easy. His expeditions won't make him rich, but he will find all his gears at the local store. However, money won't buy him the ultimate stove. The ultimate stove cost only 20 cents of supplies but one have to make it himself.
There are many light stoves available to the backpacker. Propane, white bas, hexamine, sterno, or just camp fire. One doesn't need to carry a lot to be able to cook in the wild. When the coolness of hi-tech settles down, backpackers agree that it pays to keep it simple. The stove that packs the most bang per gram, that will never fail, is so simple that no one wants to sell it. It's the soda can stove.
The extreme simplicity can be deceptive. There are several variations on this basic theme and even if most serious backpackers agree that the soda can stove is the ultimate stove, the details of fabrication is the subject of heated debates. Should one use glue? Is it still zen if you have a threaded filler screw? Open flame or pressure jets? The Zen Stoves Website have detailed instructions for many of the dominant designs. Here I want to share how I adapted Robert Butler's Cobra Stove. My variation retains the Cobra's simplicity in design while allowing more refinement in construction to produce a good looking, reliable and safer stove. I call it the Hannah Stove. This is the design that I used with great success on the Kilauea and on the North Shore of Oahu.
While I was experimenting with early prototypes, it became evident that I wanted a pressure stove. Pressure stoves are more fuel efficient and they have fewer internal parts. I wanted something easy to build but most of all, I wanted a method that would yield consistent stoves. After learning the hard way, I decided that safety was to take precedence over those two requirements. Building a Hannah Stove will take you only one hour. Lets get started with the requirements.
At bare minimum, you will need
- 3 soda cans;
- 1 wood block;
- 2 wood screws;
- 1 box cutter (just the blade actually);
- 1 3mm drill bit (anything from 2mm to 5mm will do);
- 1 electric drill;
- 1 X-acto style knife;
- 2 sewing needle.
To make your stove pretty you will also want to get
- fine waterproof sandpaper (600 or 1000 grit);
- polishing compound (yellow or green is best);
- buffing wheels.
This last list is for polishing. You could do it with steel wool but that's a lot more work. With basic polishing equipment you will have a shiny stove in no time. If you go for the shiny stove, remove the paint from two of the cans before you open them. Use the sandpaper for that. Be sure to smooth the bottom where there is not paint as well. Use plenty of water to prevent the sandpaper from clogging. Don't overdo it. You only need to clean about 5cm from the bottom of two the cans.
Now would be a good time to enjoy a glass or two of your favorite soft drink. You need to empty the two clean cans before you proceed.
Having a good time? So do I. Attach the box cutter blade on top of the wood block so that it protrudes a bit. You will use the wood block as a guide to achieve a neat cut on the can. This is a tricky part. The Hannah Stove doesn't use glue or sealant. That means that you need to fit the parts really tight. You can only do that if the cut is really clean and straight. You will probably need to use a spacer to adjust the blade height. Find something to put either under the wood block or under the can so the blade is about 2.5cm from the bottom of the can.
To get a real clean cut, you need to push the can firmly against the wood block but only slightly against the blade. Technically, the vector of your force should be almost orthogonal to the side of the block and at most 20 degree against the blade. You then just rotate the can until the blade passes through. This will take at least 20 turns. You budgeted one hour for the whole thing, right? The final cut should be really straight with almost no bumps toward the inside. Minor bumps can be dealt with. When the blade goes all the way through at one point, it might start to jam when you rotate. You should be able to separate the two ends by wiggling them gently without more cutting. I mean, really gently; no bumps.
Once you have cut the two cans, it's time to assemble your stove. The Hannah Stove is press fit. If you have peace of mind, you can just align the can bottoms and fit one right into the other. It is easier to do that if you enlarge one can bottom a bit. That's what the third soda can is for. This can should still be sealed. Select the can bottom with the less inward bumps, this will be your stove bottom. You will ram the third can into it. The only way to take the third can out afterward it to use vapor pressure. Pour a few drops of water in your stove bottom and ram the third can in it. Of course, when I write "ram", I mean "really gently push downward". If it didn't get stuck there, you are all set. If it did, pour a few drops of methanol in a pan under the two jammed cans and set it ablaze. Both will just pop apart. That or the unopened can will explode. It doesn't happen often but for this eventuality you might consider replacing the unopened can with a can filled with plaster.
Some people claim that packing some absorbent material in your stove improves vapor pressure. Others say that it slows down the pre-heating. Both are completely missing the point. Ultimately, you want to use your stove in some unfriendly, and most likely, uneven terrain. The benchmarks you make in your kitchen are nice but they should not take precedence over real world usage. So, imagine that your stove tips, and I assure you that it will. You have a pressure stove and it will spit out its flaming fuel as fast as it can. Also, you are bound one day to forget to put back the refill cap. When you light up your pressure stove, the least that can happen is an internal explosion. This will spray flaming fuel all over the place. If you are unlucky, the stove will blow up, spraying flaming shrapnels instead. Packing might affect the performance of your stove, it might improve it or it might decrease it. But, this is not why the Hannah Stove uses packing. Packing is for safety.
The Cobra stove is clever with that regard. There is no refill hole on the Cobra. The refilling is done through the jets. The jets are small enough to prevent fire from entering the stove. This has two problems though. The first is that refilling the stove is really slow. You need to wait for the fuel to go through those really small jet holes. The other problem is that the stove is still vulnerable to tipping. Packing your stove with absorbent material solves all those problems. If the material is absorbent enough, tipping will only spill the excess fuel that is not retained by capilarity. The absorbent package will also block the filling hole from the vapor chamber. That way, you have a large hole for fast refill and if you forget the refill cap, the Hannah uses a coin instead of a screw, you don't blow anything. You just get a larger jet. This jet will be too large to be efficient and it will waste fuel but, that's the beauty of a simple design, you can simply throw in your coin cap while the stove is running to fix the problem.
So many words for a simple operation. To pack your stove, fill the bottom with noninflammable absorbent material. I use fiberglass insulation fiber. Perlite and vermiculite is also a good choice.
Before you lower the top of your stove over the bottom, drill the filling hole. If you don't, the air pressure might disassemble your stove before you are done, which is really frustrating. Start with 3mm, you can always enlarge later.
By now, if your favorite soft-drink is the same as mine, you should have peace of mind; you will need it for the next part. This can be really frustrating but if you followed all the instruction properly it will work, eventually. The top of your stove is a little bit smaller than the bottom. You need to lower it really straight into the bottom and to tap it gently until it fits mostly flush. To get it started, you can cut a section from the top a of can that you will use a guide. You need peace of mind while assembling any kind of zen stove, but especially while working on those that don't use sealant.
If you wreck one or both part, don't worry. You lost at most 20¢. Just cut another soda can and try again, with peace of mind and a stiff drink. When you finally get it, you can make the jets. The easiest way to have the jets aligned is to use a hole model. I made mine (SVG) with the star tool in Inkscape. I set the number of arms to the number of jets that I want and the inner radius to 0. The template section of the Zen Stoves website has several ready made hole models.
How many holes you want depend on the size of your needle. A lot of small holes gives best result. I use 24. Fix your hole model on top of the stove. Blu Tack works well for that. Cut a needle and fit it in the X-acto handle. To prevent the needle from breaking, cut it so that it protrudes at most a few millimeters. You can enlarge your holes later with a longer needle.
You are now ready for a test run. Your new Hannah stove needs pre heating before it can build the vapor pressure that will sustain the jets. All what you need to do is to pour a few drops of alcohol in a pan beneath the stove. Go ahead, pour 30ml of alcohol in the stove, a few drop in the pan, drop a coin over the filler hole, and set everything ablaze. Wear protective gears, too small jets will generate excessive internal pressure and can blow the stove up. Note that using a coin prevent massive pressure buildup. The coin just lift when pressure is to high. If your stove does a few backfire like explosions, it's the coin releasing the extra pressure.
Don't worry about boiling anything yet. Just study the jets. If the jets are hissing and can't sustain a flame, they are too small. If the flame is more than 10cm high, the jets are too big. It is also possible that gas pressure is leaking from the seam where the two ends are joined. It might be that there is a big bump at that spot on either of the cans, that you removed too much material with the sandpaper on the top part or that you enlarged the bottom too much. It is easy to enlarge the holes but all the other problems will require that you cut two new cans.
Once you are happy with your jets, you can see if they cook well. With 24 holes, I use a 5.5cm high mesh pot stand. Depending on your fuel type and your hole configuration, you will want to play with the pot stand height. Making a pot stand will be easy. You just need to cut a strip of steel mesh. Folding wire works just as well. The idea is to play more with the pot stand because it is easier to adjust that the jets. You new stove should bring 500ml of water to a rolling boil in 6 minutes with 30ml of ethanol.
Once your stove is finely tuned, you should give it a good shine. Aluminum is really easy to bring to a near mirror finish if you use the right tools. The idea is to level the scratch pattern and to progressively reduce the scratch size until you have something close to the wave length of visible light. Check this quick introduction by Caswell. Aluminum is a soft metal and your stove is really small. You can move quickly from one step to the next. With a little extra work, the technique you are going to use can bring a motorcycle frame to a mirror finish.
There are a many places where you can get your polishing compound. Jewellers supply stores have a large selection at competitive prices. For some reason, they don't like it when you tell them you want to polish soda cans. Find an interesting story to tell if you go see them. Wood working stores will also have some polishing compound. Not a large selection but you only need a medium one anyway. You can always fall back to Caswell. They have all what you could wish for. Grab a medium cut, either green, white or yellow and a buffing wheel. I also like to start with a fast cut; black or brown is perfect. You should already have smoothed your stove with 600 grit sandpaper. You might want to give it another pass to remove any scratches that that occurred while assembling. Rub the buffing wheel against the compound block then against your stove. Change the angle for each pass but try to keep it nearly perpendicular to the previous pass. Black compound gives an interesting finish but it is yellow that gives the real shine. To get a mirror finish, you need to smooth everything with 1000 grit sandpaper and to get down to red or blue compound, which I didn't do for this tutorial. When you use more than one compound, start with the fastest cut and progressively move to slower ones. Using more than one compound makes it shine faster but your tiny stove will shine soon enough even if you have only a medium cut.
You now have the ultimate stove. It is ultra light, good looking, dependable, safe, easy to use, efficient and you built it in only one hour, without fancy tools or measurements. Do not despair if it doesn't work well or doesn't look good the first time. It can take a few attempts to get it right.
Comments
Eric, the inner wall transfers some heat from the jets to the pool of fuel at the bottom of the stove. This increases evaporation and improves the jets efficiency. For safety reasons, I prefer not to have a pool of fuel in the stove. That makes it too vulnerable to tipping. The Hannah is a bit less efficient for that. The design on Instructables uses a lot of jets in the middle to allow fast refill without the danger of a filler hole. I tried that and the middles jets were really inefficient. I think that it's because they can't breath enough. I could improve the boil time by just dropping a coin over the center jets.
Thanks for the link.
very nice! I have used alcohol in a tuna can for years, all by itself. It works fine, but you have to plan ahead as it takes a while to boil water. This is much cooler though I must admit, I will give it a try for sure! I would just add to not forget some sort of reflector around the entire contraption to retain heat and deflect wind. Also, polishing metal is best accomplished using successive compounds, ending with the finest one. In other words, go in order, don't just skip to the end...
Interesting article. I just love the simplicity of the design. Although I have no use for one I'm going to have a go at making one.
Great idea, I'm definitely going to make one. This might be stupid, but I'm curious though, does the size of the coin matter a whole lot? I know a heavier or lighter coin would move to release pressure at different times.
Pretty neat. I think this would be great to have around the house for emergencies as well as camping.
Hm, how is this different from the 'penny alcohol stove' seen elsewhere?
Clint, I haven't done serious measurements but I doubt that it would have much impact. The backfires occur only when you start the stove if you primed too much. A simple system to prime just enough would probably be a better way to improve efficiency. But keep me posted if find an optimal coin.
JBB, the Hannah borrows a few ideas from the Penny stove. Both a soda can stoves so of course there are many similarities. I think that the Penny was the first to use a coin for pressure regulation. The Hannah is more simple to build; you have only two cuts to make and you have a lot of wiggle space for the height of the cuts. The Hannah uses a lot of small holes insted of a few big ones. During my tests, this was more efficient but I never had a chance to compare against a well built Penny.
Yannick, this thing is awesome. Well done. I built my first one last night but it does not work so well. Big tall yellow smokey flames. I relate that to not enough pressure. The cans seem very tight though. It took a lot of peace of mind to put the two together.
I think I have a few problems. First will this thing run properly on white gas?
How critical is the placement of the jet holes around the can. Is higher towards the rim better than lower? Lastly how small are these jet holes? I mean my sewing needle is pretty tiny and is fragile trying to poke through the can. Thanks, Namrek
Nice stove and instructions. What are you using for the pan below the stove? I'm sure a lot of things will work but what you are using looks like a good choice.
I use the top of frozen juice concentrate cans. I stack two of them to provide a minimal thermal shielding. It looks good but it it a bit to small. I need to lift the stove on the side of the primer pan for pre-heating. You clearly see it in this picture.
twenty four holes are too many to get blue flame only. based upon my tests, the maximum number of holes to minimize (cannot be eliminated) the cooler yellow flame is sixteen. i tried 32, 24, 20, 16, 12, 10 and 8. the lower the number of holes the longer the flame is. of course you also have to consider the hole size as well. sixteen holes made using a push pin will result in lots of yellow flame. do your tests.
could you compare your stove with Mark Jurey's penny stove?
http://www.csun.edu/~mjurey/penny.html#
I built a couple stoves using your design exactly, each with different jet hole sizes (both with 24 jets) made with hand-sewing needles. My jets appear visually similar in size to yours. I did several tests using 30ml denatured alcohol and had results that look identical to your pictures.
I'm very curious to know what burn times you get with 30ml of fuel, as my results don't seem efficient enough to be very practical. My typical burn time averages between 5 and 6 minutes at full output, then tapering off over another minute to nothing. So while I can just barely boil a pint of water, the stove is exhausted too soon to actually do useful cooking. It's not a priming issue, I'm using just enough priming fuel in the pan so that it's exhausted just after the jets ignite.
Some stoves with similar designs manage over minutes burn duration with similar boiling times on 30ml, and some low output designs claim simmering heat for over 40 minutes on 30ml.
So, do you also get useful burn time of less than 7 minutes with your design? If not, how long does 30ml of denatured alcohol burn in yours before it tapers off and goes out?
Thanks for sharing your elegant design in such a well-documented way!
I just did a timed test with 30ml of methanol (I don't have denatured handy):
- 0:20 pre heating done, jets kick in
- 5:20 rolling boil
- 6:45 power is waning
- 7:45 dead
It dies around 12:00 with about twice that fuel. You can make a simmering rig by just covering some of the holes with another can bottom. If you need to simmer, a mini sterno pack might be better. The really small ones are not powerful enough to boil but they simmer for 60 minutes. They weight only 75 grams.
You are deserving of much Slack for this design and especially for the clear instructions.
Question on the burn time: How much fuel can the Hannah stove safely hold and/or If you find that you need more time after the fire is almost out, is there a way to refuel and continue? Do you need a second stove to swap out?
With a 2.5cm stove bottom you obviously can't have a lot of fuel in there. I just did a test with ~75ml and the stove started to spit out it's excess. I had a burn time of ~14:30 with that. You can always make a bigger stove if you cut your soda cans higher.
Don't refill a hot stove. The alcohol flames are pretty much invisible in daylight. If you have two stove you can swap them. I just grab the stove. When I can hold it in my hands I'm confident that it's dead. After a few hikes, you know you stove pretty well: 20ml for a ramen, 30ml for eggs and 40ml for beans. It's part of the fun. In doubt, just fill it up until is it spills. After that, your priming pan is also ready.
Yannick; Very nice! Cookies for you!
A small suggestion. I think you will find a significant improvement in boil times if you use the wind screen.
A total height of 4.0 cm (this is the two cans already put together) obtained a burn time of ~30min with ~65mL of 2-propanol (rubbing alcohol). I'll share further experimentation here.
Very cool, I quite like the simplicity of the design! I remember having to build these kind of stoves for the old scouts survival courses. For cutting the can (if you have this luxury) a lathe is incredibly usefull.
maybe i just missed in the article and maybe im about to sound retarded but how do you light it? is it just the preheating getting the fuel to vaporize and come out of the jets?
cool design by the way
After you pre-heated enough, the vapor coming out of the jets will just ignite on the flames licking the side of your stove.
Awesome job Yannick. I've been working for the past few days on stoves based instructions on zenstoves, but your instructions rock! The design I'm going with is the open jet style, which has jets of course, but at a much lower pressure since the middle is open. I've gone that route to eliminate the need for priming, but at the expense of a less efficient system (debatable). I do like your thoughts on using absorbent material, though, that is definitely a plus to your system. It could be used in other designs as well, but probably not be as useful as how you use it in the Hannah.
Also, I had considered going the high shine polished route, I think it looks clean, but what I'm thinking about doing for my end-result stoves is to instead rough the aluminum up a little and put a finish of high temp grill paint on them to help them survive longer. Do you have any thoughts on that?
I saw an open jets stove with packing in the inner wall somewhere. A bit troublesome to build but you get the safety. I don't know if you can pack the bottom with open jets.
High temp paint would look really good. Polishing looks good but it makes pre-heating harder. After polishing, you need more fuel in the priming pan. The reason is obvious, the shiny sides reflect all the radiation and you heat only by convection. Of course, you don't need to pre-head an open jets stove so this will not affect you.
It won't be easy to get a need and even paint job on such a small curved surface. I'd try with an airbrush and lots of thinner in several coats. Alternatively you can always use a few thick coats and polish the paint. Cars used to be lacker painted than sanded and polished. It looks good. Beware not to clog your jets. It should be possible to anodize it. That would give a kick ass finish. Send in some pictures when you're done.
Cool thanks Yannick. I thought about the possibility of clogging up the jets when I was considering the paint. I figure sticking pins in each of the holes while painting should keep paint out of them. Maybe drilling them out again after the paint cures just to make sure.
You're right, the paint won't be easy, but I'm pretty good at patience and typically put several (like 5 or 6 or more) thin coats on similar projects where the normal person (and manufacturer usually recommends) 2 to 3 coats. Should turn out ok. May not end up perfectly even, but close, and if it lasts just a few times instead of forever that'll be fine by me. After all, it's a soda can that was destined for the trash anyway :)
Thanks for the link to the anodizing technique. I haven't done anything like that since college. I doubt I would take it that far, but that would definitely give it one kick ass finish.
Hey, This design, and instructional rocks. Just thought i would say first off. I love how u placed your favorite soda in nearly every shot... cudos ;) Also, I am a member of a rather serious MILSIM Airsoft team. Our Games usually last between 8-24 HRs. We have been in the market for seeking out camp fire stoves. Problem is, all the ones that are light, compact, and efficient... are really expensive. I mean sure there is always the use of Hexamine fuel tablets. but these become expensive as they are NONE REUSABLE. Compared to the build costs of this stove, and the fact that we can reuse them, considering the space saving, and light weight This is by far the best option. Cheers and thanks for the instructional.
Hey just wanted to inquire, What did u use for a primer pan? looks to me like a tuna Can thats been side cut, can u advise?
I use the top of frozen juice concentrate cans. It is actally a bit too tight, you might prefer something larger.
Very impressive design!
I made one once very similar. I think your holes are well placed.
After I made the soda stove, I made a pot holder/wind break using a Red Gold Salsa can. This can is pretty low and squat. All I did was cut four notches out of the top and bottom. Works great!
The whole thing fits inside a titanium pot.
Doug Roberts Columbus, OH
Cool deal, worked great, first go. I wonder if you could make the bottom bigger, to allow for more fuel capacity?? Or could you load this one more than 30ml?
You can easily double the capacity if you make your cut higher on the soda cans. See this thread for more details.
What's the deal with the "Hannah" ? Is the can stove jewish ?
Ophiophagus hannah is a species of cobras.
name "Hannah"
Peace of mind?
Easier way to polish: Simply use paint stripper (or "Goof Off", found at your hardware store) to remove the paint. Now you have fresh aluminum with no scratches, and only need the final polishing compound.
This also prevents you from thinning the metal, and makes a smoother surface to mate the two pieces.
Dude, this is a FANTASTIC how-to, but I can't help but wonder if one of those round Altoids cans would work better. Not that I'm averse to all the work, but still. . .
Great stove . I have found that if you use a Heineken can for the lower half, cut it on a 3/4" piece of wood stock, the cut goes just at the bottom of the 'band' around the can, so it has a natural flare that allows easy but tight insertion of the upper soda can. No third can needed! Also, Heinie's are a bit thicker and stronger aluminum. Cheers.
I did a test run using some very rough cut cans that I chopped with a dremel. DO NOT DO THAT, it was impossible to get a straight cut with my ghetto rig (which was me holding the can on the edge of my workbench while I tried to hold the dremel still). I found however that if you heated the bottom over a flame for a few seconds it was much easier to get the two parts together.
I tried to heat the bottom and put the top in the fridge. It works but you have to work really fast because a thin sheet of aluminum gets back to room temperature in no time. A Dremel is really good for polishing. Did you get a nice finish?
I didn't bother polishing it, this was only a test. I've got three more cans that I'll use to make another one, but this time I'll try cutting it cleanly.
And I did try freezing one half, but that didn't work well as the heat from my hands got it back to room temp pretty much instantly.
My favorite part was the Dobbsheads, but the stove design looks very simple and I might have to try it sometime!
Hi,
I made an open top stove with side burner jets, and an open top stove with top jets. Much like the pepsi can stoves. Outside the flame is very fragile to wind etc, and gets blown around a lot. The fuel seems to burn yellow and does not come out of the jets very well.
I used a pushpin to make the holes and incresed them in size to see if that helps. But to fuel still struggles to burn from the jets.
Any ideas.
First of all, you probably need a windscreen when you use it outside. I use cheap aluminum foil, check the Zen Stove website for fancier designs.
If your fuel burns yellow, you probably use something with too much water in it. Rubbing alcohol by any chance? Try with fondue fuel. Don't expect pretty jets like in my pictures with an open top stove; you simply cannot build as much pressure.
Thanks for responding.
I tried the stoves inside and got the same result.
I am using Meth/Ethanol as fuel. Someone explained to me that with an open top stove, you need a sidewall, otherwise the fuel burns from the open port only.
What do you think.
You need either an inner wall or a design where you let the pot sit on the main chamber when the stove is hot enough. As you can see, open jets are a pain to build. Try my design, you can't possibly not have a working stove with it.
Nice guide, tried this yesterday and got a working stove on my secound try. Think i made the holes a bit to large tho, 15cm flames might not be optimal. ;)
Will try again once i get more cans.
Once again, thanks for a great guide!
I've put 4 hours into making one of these babies to no avail...I just meditated to help with the "peace of mind" but still couldn't fit the halves together. Anyway, most of my time went into cutting the cans (which took me over 100 turns, not 20), but I discovered that I can make a super-clean cut using scissors and a file. Turn the can against the blade like the method describes here to give yourself a template to cut against, then use scissors to cut it. Use your head while doing this, as you can't make one continuous cut, and need to cut off 1-2 inch sections at a time. The cut is clean with no bends, and if it's not, take a file to it.
I "stretched" the can using the third can method but cannot fit the two halves together! Necesito mas zen.
You have to use three soda cans of the same brand. They look all the same but various brands differ enough in diameter to prevent proper dilatation.
If all else fails, you can make a super stretcher tool: take an unopened can and slide it into a can bottom that has a single hole in the bottom floor. The unopened can with the sleeve over it will have a lot of enlarging power. That will probably in fact make your enlarged can bottom slide so easily that you'll need some sealent; J-B Weld is a popular choice for that.
Good luck and be sure to try a few stiff drinks to get peace of mind.
Thanks for the info; I've been using different brands, so I'll try the same one and get back to you. I really like this method because it uses no sealant, so I'm trying to stay away from the J-B Weld...
I find easier the cut when you fill the can with water and freeze it
you rock great hobby
I do the exact same thing with the frozen water. I use a drill press with a dremel cut off wheel to make the cut. IT takes at most 30 seconds to cut the can. Every cut I have done so far is perfect. I can really pump these things out now that I don't have to spend 30 minutes cutting cans. The finished cut is also much cleaner than anything I was getting with the razor blade method.
Anyone have any explosion stories they'd like to share?
my first stove blew apart. I don't know what happened. It has not happened since though. I just got back from a 3 day trip. The stoves worked pretty good. I brought 2 so when one ran out of fuel I could pop the other one under there.
I used the top of a tuna can for the preheating. I just used one of the can openers that cut the lid from the outside rather than the top.
I would like to come up with a simmer only stove. So far I have not hat much luck.
Why not prime the stove by covering the hole on the top with a penny, then filling the top "cup" as is done on the penny stove. As the alcohol heats up, it primes the stove and seeps under the penny.
I've made the penny stove and have been impressed by the boil and simmer times as compared to the open ones. I am now going to try this design and see how it compares.
For a simmer ring, I took a can opener to the top of a can to remove the top, keeping the raised edge, then cut the top off the can. Once boiling, I put the ring on the stove and it simmered away nicely.
Great instructions and illustrations btw...
Thanks.
Heat rises; you'll only need a few drops of fuel to prime with a pan while you'll need a spoonful to prime with the top cup.
I find mini sterno packs quite good at simmering: they don't pack enough heat to get a quick boil but you can get them going on short notice if you find that you'd need to let your stew roll a little longer. You can't recover the unused fuel from the soda can stove; that makes it suboptimal for simmering.
You state
"the least that can happen is an internal explosion. This will spray flaming fuel all over the place. If you are unlucky, the stove will blow up, spraying flaming shrapnels instead"
Alcohol is non explosive. I have been making and using these types of stoves for the last 10 years at least, and have never seen nor heard of one "spraying flaming shrapnel"
decent write up otherwise, oh the other thing I found odd is that it takes you an hour to build one of these?
Ok, so, in starting, i would say that you really should try a sideburner design. this allows the pot to be set directly on the stove.(Also, if you set a pot directly on an open jet sideburner stove-the ones with the open center- performance increases to that of a pressurized stove) Second, instead of priming pans, I'm experimenting with priming wicks made of flameproof fiberglass. You get faster priming, and no hastle. Third, I suggest that for beginners, instead of stretching the bottom half, they use crimps on the top half. this allows the halves to have a tight fit, but you dont need any sealants. I find this method really easy, and it lasts a long time.(oh and by the way, this method makes the stove 100% recyclable) I also find that scisors make REALLY REALLY clean cuts for the top and bottom can sections. An inner wall is easy to make (as long as you punch holes in it to prevent overpresurization) and increases the stove strength. And also, I recomend that you just leave the original manufacturer's paint on the cans. Within a few burns, the plastic integrated into these paints fuses together and "bonds" the top and bottom sections. I find that after this, the peices are very hard to separate.
Thanks for the tips. I tried the side burners but the pot gets quite unstable. It must be great with a cat stove or a tuna can one but a regular pop can simply doesn't have a large enough footprint. What pot do you use?
Oh yeah, with the crimp method, you also dont need a shim to fit the parts together. All you have to do, put one peice on top of the other, and twist a little until all of the crimps pop in. I usually, for a 12 oz can, use 8 crimps. These can be made with a pair of needle nose pliers.
I'd advise against using perlite/vermiculite for an absorbant - it clogs the holes. I tried making a little one from Stella cans (I guess Red Bull is about the same) but it didn't hold enough fuel. I made mine about 25mm tall (1 inch) and it holds just enough fuel to boil a canteen cup. I'll field test it over the Xmas hols.
Would aluminium foil work for a priming pan I wonder? I smacked a pasta sauce jar lid into the right shape - it holds the stove up off the ground a little for improved airflow & heating.
Vik :v)
Awesome instructions. After a couple of botched attempts and tired of cutting cans, I thought there had to be a better way to cut them. I thought what the heck and used my compound miter saw, to my surprise it worked great. It works best to go slowly so the blade nibbles away the material away rather than rips it. Aluminum is soft enough that you don't need to worry about it ruining your blade. If there are any burrs lightly sanding will clean it right up.
For the priming pan I used the bottom of a dog food can cut off with a grinder. It isn't aluminum so I'm not using my compound miter saw, although I'm sure it would probably work too.
Again awesome website.
Nice design. I built one before, without the penny feature. It worked, but not as good as this design. To prime, I just hold a flame to the bottom of the stove for 1-5 seconds, set the stove down, and it's ready to light.
nice design. any sugesstions for sealing the two halfs together? Or do i not need to?
If you pick two cans of the same brand, you don't need any sealing.
What do you think about the "pressure" jet stove with the screw on the top?
Those with a spring are safe, those with the screw bolted on can build excessive pressure: they will shoot one foot flames or might even blow up if you prime them too much.
The gain is marginal but if you have all the supplies lying around, sure, go ahead.
does your stove have the middle section that i have seen on other modles?
Thre is no middle section. I tried to do for a design as simple as possible.
So you didnt have any troble lighting or an explosion(more of a big pop actually)? Cause I did. What did I do wrong?
This is probably because your holes are too big and that the flame can enter the stove through them. Try with smaller holes and make sure that the stove is completely filled with fiberglass.
What is the third Can for?
You use it to enlarge the stove bottom.
Hey,
For some reason whenever i want to light the stove it wont light up, I dont know what the deal is. Its my First time making a stove. Can it be that my jetz are too big? can it be that my Hole on the top is too big/small?
what i do is: ( i use 70% Isopropyl Rubbing alcohol) I poor some of my Fuel on a Tuna fish top. i place the stove ontop, put the Quater on the top of the stove and light it up. after a few seconds ( 5-10 ) the fire dies and it stopped.? any help? ( jets are 3 mm's the hole on top is 7 mm's ) here a pic: http://img208.imageshack.us/my.php?image=picture004largehv5.jpg
Hi Dominik, your stove looks good. You should have no problem to light it if you move to a better fuel than 70% isopropanol. You should have no problem finding a 95% or better fuel; try fondue fuel, denatured alcohol (sold as paint thinner) or gasline de-icer. The high water content in rubbing alcohol is sipping away all the heat so your stove can't stay warn enough to build a strong vapor pressure.
I have made about 10 of these, trying different burner hole sizes and different cans. The best cans are Heineken beer - thicker and they have an out bulge that, if you cut along the edge of, gives you an insertion lip for the burner can. Best to use 2 Heineken cans though, the regular ones are a little too small and there's leakage between the cans. Priming the stove with a little alcohol under it does work. I like to heat it up a bit with a lighter, takes only 20 secs, and works well in the winter.
When I cut the cans I don't cut all the way through. I set it up just like you did, with the blade on a block and all. But rather than cutting all the way through I just go around a couple times to get a good score on the surface. Then I cut the can all the way through about halfway up, not worrying about clean edges. If you make parallel cuts from there straight down to your score line, you can just bend the tabs back and forth a bit till they come right off, giving you a perfect edge. I also find that in a pinch, it's not hard to make one of these using only a pocketknife.
Made a few of these already.......everyone is getting fat from all the soda!. I found the best way to cut the cans is fix your Xacto blade onto the wood block so about 1 cm of blade protrudes from the face of the block. (Put the block in your left hand and the blade in your right hand parallel to each other sharp side of the blade to the right.Now tilt the bottom of the blade towards your left hand just a little.......keep this angle and attach the blade to the block...confused???) Hold the block firmly and rotate the can against the flat of the blade, not the point, several times.After you have made a really good score around the can, apply enough pressure to the can to pierce it a little....now use your fingertips to "peel" the 2 sections apart.If you have kept your can steady during the scoring and peeled the 2 sections apart carefully, there will be absolutely no burrs or jagged edges.
I have just begun making soda can stoves, and my first attempt looks good (despite a split in my bottom can when trying to stretch the opening). Regardless, I tried lighting it to experiment with my hole configuration, and I found that 12 holes tapped (<1mm) with a sheetrock screw made very good blue flames similar to medium on a gas stovetop (ignoring, of course, a larger flame coming from the crack in my bottom can).
However, when I place a penny on the fill hole, the flames quickly fade out as if I've cut off the only air intake, any solutions?
Just a question regarding those mentioning Heineken cans...Are these the little rounded "keg" cans?
Hi, this design looks good, I was just wondering, is there any way to safely extinguish it, or do you have to wait for the fuel to burn off?
Inode, for the windscreen just cut off the thick top and bottom part and use wats left of the middle... with a little reinforcement you can make that ur pot holder also
Two questions.
Would petrol (gasoline for those of you across the pond) be a safe fuel?
Is there a similar method of making a camp lamp?
use gas if you want to blow your hand off...
A friend and I did an extensive study and developed a stove that looks very similar to this one (the Schmidt-Marshall Mk 14, not as catchy as The Hannah, I know.) Its a 16-hole-coin-no-sealant-no-anything-inside-it type affair. The only primary difference is that we found that if the rim of the bottom can protrudes slightly above the jets it acts as a sort of wind block/ primer lip/ heat reflector/ pot holding rim. To prime it, put fuel in the lip between the "rim" on the bottom of the top can and the outside wall of the bottom can. Heat is conducted down the side wall into the fuel, thus it takes a bit more fuel than "bottom priming" setups, but less than "center primers" We cut little notches between each of the jets so you can set (albeit a small) container directly on top. No tray underneath, no wind-block, no pot holder.
Oh, and whatever you do, do not use common gasoline (or petrol for those of you back across the pond.) Gasoline contains benzene and weird additives designed to keep your car's engine clean, it would probably get your insides nice and clean as well. That, and gas produces lots of soot that can eventually clog the holes. Coleman fuel or paint thinner are better choices.
I was wondering if filling the cans with water and letting them freeze would simplify the process. Not only would the cans be easier to cut but they would be expanded by the freezing water inside. Then maybe you could heat the bottom up (to shrink it)allowing the two pieces to easily go together, before heating the top to tighten the fit. I haven't tried this out yet, it's just speculation. If anyone out there has let me know how well it works. I would imagine the biggest concern is that leaving the cans filled with water in the freezer too long will cause the cans to "explode" or over expand and tear.
Kyle if you ctrl + f my comments that's exactly what I did. I freeze the cans half full of water and then use a cut off wheel in a drill press. I get perfect cuts every time and it takes almost no time at all.
Love the plans Yannick! My skill at "reproducibility" leaves something to be desired. 1st attempt was a dud from a seal leak (inner piece "crinkled"). 2nd stove is a champ tho... that one is going hiking with me this weekend. 6 solid minutes on 20ml of fondue fuel! 3rd stove is interesting... it melts my penny at or near the end of the burn! :-) I wonder if the stove allowing fuel to burn under the fill hole? Great fun, thanks!
Pennies that are minted from 1982 - Present have a 97.5% zinc composition, and will melt if they're heated long enough. Pre-1982 pennies are predominantly copper (95%) with the exception of zinc-coated steel in 1943.
Don't solder the two cans together my wife & I decided to do that and when we lit the stove after a few minutes it exploded, I assune due to the fact the air couldn't get in around that area which is probably required. We are still trying to work out Y it exploded. By the way when we did light the stove we where at a gunclub facility so no damage was done.
This is a great how-to page. I found a similar one on Intructables.com, and linked to this page in a comment over there. The Instructables one uses a middle wall. I wonder what the pros/cons are for having it?
http://www.instructables.com/id/ENM6M5MNFFEP287L7C/