Backpackers and outdoors enthusiasts are constantly trying to shed weight, especially those who call themselves ultralight backpackers. If this is you, then you're in the right place. Even a rocket stove weighs around one ounce, and the smallest can of isopropanol gas canisters are eight ounces when they are full and four ounces when they are empty. This little DIY camping stove made of tin cans, or, better still, aluminum cans weighs mere grams. A liter of alcohol weighs about 0.75% more than a liter of water and can be stored in plastic bottles. You can carry less fuel. You can't get much more lightweight than that.

There are a few downsides to alcohol stoves. They burn cooler. The "normal" backpacking stove often comes with a pot stand, sometimes even with a windscreen. White gas stoves are best for extreme cold weather (less than 30°F). So, if your outdoor adventure takes you someplace where a pan of boiling water means survival, then these DIY camp stoves are not for you. In windy conditions, it can be tricky to get an open flame to get a cooking pot of water to boil. This is where a Jetboil really shines (it takes less time to get to a boil). These little stoves might not pack as well, but if you're careful, they should last you a long time. If not, you can make a new stove while sitting in a shelter. Tear a small can or a large can of beer apart, and charm your trailmates while building a DIY alcohol stove before their very eyes. Six-packs come in a quantity of six (three stoves)—make portable stoves for everyone!

Getting Started

The simple tools you’ll need will depend on your level of orderliness—mine is moderate while at home. A thousand miles into a thru-hike, and I’ll make do with whatever I have on hand when my stove gets waffle-stomped. I used: a marker, a brad (tiny trim nail, very sharp), vice grips, a heavy-duty razor blade, needle nose pliers, scissors, cordless drill, and, depending on design, 1/16” and 3/16” drill bits.

Materials

Alcohol will be needed eventually, but you can also start with alcohol as one of the first materials. Making beer cans empty is more fun than making empty soda cans. But, playing with sharp metal, razor blades, and power tools … it’s your call. You’ll need two cans of the same diameter. The diameter you use should be based on the pot you have. If the cans are too big, the flame will be along the edge of your pot and not under the pot. Too small and you risk it being unstable.

Below I have a large Foster’s style can (32 oz in this case), a regular 12 oz soda can, and one of the small 8 oz soda cans. Interestingly enough, the bottom of the can diameter of the small soda and regular soda are the same as the inner diameter of the recess.

Design

There are a few designs out there. Two that I know of were using soda cans, and another was using a cat food can or a soup can (not covered here). Both of the designs below will work well. One is a little lighter and a little easier to make, especially if you’re out in the woods without proper tools. That said, I like the other one based solely on visual aesthetics. Construction is the same up to a certain point. The one on the right is the simpler design. The one on the left is a double wall, and it looks cooler.

Accessories

Use the bottom of the large can for a snuffer, and use tin foil for windscreens.

Construction

To start with you’ll need to cut up your chosen beverage cans. Start with a block of wood, a book, or any semi-hard surface that is about an inch to an inch-and-a-half high. Use this and the flat razor blade to score a line around the can. Hold the razor in place with a finger on top with the end overhanging the edge. With the other hand on top of the can, slowly spin the can while pressing it against the blade. If you run the can against the blade several times, scoring deeper each time, it will make cutting the can much easier. In fact, scoring well enough and just pressing along the line will get the can to split apart. Watch the sharp edges.

You’ll need two bottom pieces. One will be the stove base, and the other will become the top with the jets. Reserve a top half if you’re going to make the double wall design. Score and separate two cans for the top half and bottom half. Or you can use a marker line and scissors.

Next up is drilling the holes along the edge of the can. These will be your flame jets. I used the brad to dimple or even start the holes. You don’t have to use the drill on these. The goal is to have 16 evenly spaced holes that are roughly 1/16th of an inch in diameter around the outside edge of the recessed part of the bottom. The easiest way to do this is to mark the four opposite sides, and then divide the space between each again. This gets you to eight burner holes. Divide the space evenly again for the additional holes until you get to 16. Once marked with the brad, I go back with the drill. Dimpling or piercing the can with the brad keeps the drill bit from walking. This will be the top half of the stove.

Simple Design

At this point, you need to decide on the type of stove you want. I’ll explain both, starting with the easier version. Using a penny, trace a line in the center of the depression. Within that circle, mark four holes within the line at opposite sides. Mark the center for a larger hole. The four small holes along the edge are 1/16 of an inch. The center hole is 3/16 of an inch. This is where you will eventually pour the alcohol. They aren't actually vent holes, but if you get some airflow under your pot, it might get too much oxygen and burn faster. If your pot sits directly over these five holes, there won’t be any flame here.

From here, use the needle nose pliers to kink the edge of the bottom half. Doing this will make it easier to slide the two halves together. Now, it’s just a matter of putting the two pieces together. It can still be a bit tricky, even with kinking only one side. But keep at it and you’ll get it. Then, push the two pieces together and you’re done.

Double Wall Design

Having the double wall will make this marginally heavier, and harder to make, so is it worth it? Both will boil a pot of water well. I suppose if you are a purist ultralighter, this is a violation of the “rules.” Thou shalt make everything as light as possible. This should also include removing the paint from the cans, but that is too much work. As I mentioned before, I just like the looks of the double wall. It does give you one advantage. You can readily see how much fuel is in the stove. The first few times will be trial and error with how much fuel is needed. Elevation, temperature, amount of water, wind…these and more will affect the efficiency of the stove.

Using the bottom with the 16 holes along the outer edge, you’ll need to score the inside diameter of the recess. This is the thickest part of the can, and it takes a fair amount of effort to cut out the center. I used the blade pictured at the beginning, holding it in my fingers without any kind of handle. I score it as hard as I can without hurting my fingers too much. Then, I use the vice grips to hold the blade and pierce along the score. Again, if you score deep enough, the can will come apart with a little bit of prying with the blade. If not, cut and stay along the line as best you can. This is the part that would be very difficult to do out on the trail. I don’t have the jets drilled in the picture below yet.

Next, is building the double wall. With your two bottom halves next to each other, measure the side of the can. When you put them together with the double wall, the wall will sit inside the recess inside the can. See the picture below. This extra little bit of length needs to be added two times to the double wall length. On a standard soda can, this extra depth is about one-fourth of an inch. If the outside of the can is one inch tall, make the inner wall one-and-a-half inches or more. Just make sure your double wall is tall enough to be snug both top and bottom when assembled.

Using the top half of the can that you put aside, measure one-and-a-half inches from the cut edge. You can mark a straight line around the can using the blade or marker and the fixed object you used for scoring earlier. Then the easiest way is to use scissors to cut straight up the can and along the line. Do not use your partner’s favorite fabric scissors. You’ve been warned!

This will leave you with a flat piece of metal that will overlap when placed inside the bottom half of the can. Leave a little bit of overlap and trim the excess. Cut three notches in the strip — one where the overlap occurs, then fold the tab over. I fold it to the outside to give the stove a cleaner look. Leave this tab on there. You can trim the other two tabs off. Cut them about one-eighth of an inch wide and about one-fourth of an inch tall. Kink the bottom half as described earlier and slide the two halves together. Make sure the inner wall rests inside the center cutout and is snug with the top and the bottom. It doesn’t have to be airtight, but the closer to that the better. The alcohol will need to vaporize between the walls in order to get flames out of the jets, so large slots or a sloppy fit aren’t going to work as well.

Lighting the Stove

Alcohol burns much cooler than other fuels. For this reason, you can actually dip your finger in alcohol, light it, and use it to light the stove. Because alcohol burns almost invisible in the daylight, I do not recommend doing this. It burns with a blue flame in the dark. Alcohol does burn hot enough that it will burn you if not put out fairly quickly, but you don’t need to totally freak out if you do accidentally light yourself on fire. And because it burns cooler, it may require more time to get your water boiling.

Because the stove isn’t going to operate correctly until you get the alcohol to vaporize, and because you can’t see it burning, it’s best to use a “drip tray” under your stove. You don’t want to start a wilderness fire by bumping it, but that’s not why you need the drip tray. A lid from a pickle jar, jelly jar, etc. works as well. I swiped the metal lid from one of my girlfriend’s fancy candles. It’s a perfect fit for my Toaks 650mL pot, and it’s lighter than a jar lid.

With the stove in the drip tray, fill the stove with about two tablespoons of denatured alcohol. Rubbing alcohol (99% isopropyl alcohol), HEET (antifreeze for fuel lines), and fuel tablets (hexamine) will work as well. At least one of these should be available in any gas station, drug store, or hardware store. You can’t say that about white fuel or isobutane canisters.

Using the liquid fuels, pour a little into the drip tray as well as the two tablespoons in the stove and light the drip tray. You only need enough alcohol in the drip tray to burn for about a minute or two. This gets the internal temperature of the stove hot enough to vaporize the alcohol inside the stove.

Once it reaches temp, it’ll burn on its own and the jets will burn without more fuel in the drip tray. Two tablespoons of fuel should burn between 10–15 minutes. Be careful to burn all the fuel and that the stove is out before messing with it. You can make a snuffer with a larger diameter can if you like. This will ensure it is completely out, and you can then save whatever fuel didn’t burn by simply pouring it back into your fuel bottle. An amount of 750mL should last about 10 days, so schedule resupplies accordingly. Once the stove gets to the temperature and the excess fuel burns off, you’ve got almost the same as the gas burner on a regular stovetop, just with no dials or knobs. If you notice the bottom center of mine, there’s a flame coming out of the side. I’m not going to worry much about it, but if you want it to be tidier, then either straighten the metal out or wrap it with a piece of high-temperature metal duct tape. Home Depot, Lowe’s, Menards, and even Ace Hardware will have it.

If you use a penny to block the center hole, know that in mid-1982 the US Mint changed from all copper pennies to a zinc blank that is copper-plated. If you have a 1982 penny, flip it in the air, and it will zing if it’s copper. If it clinks, it’s copper. 1981 and before you don’t have to worry about it. Apparently, this is what happens to a zinc-based penny when you set it on fire for five minutes. This won’t happen to an all-copper penny.

Should you have any questions on this design or other ultralight camping stoves, reach out to a Camping & Hiking Expert here on Curated!