I am not the inventor of this stove, and there are far better designs out there (Penny Stove is the best!), but this pressure-based alcohol stove is by far the easiest to make.
Watch the video for an overview:
Step 1: Supplies
1. Two pop cans, or beer cans.
Make sure the bottom of the can is free of dents and scratches.
2. Fine sandpaper.
320 or higher grit.
3. Utility knife blade.
5. Wire hangar.
6. Fiberglass (optional, but recommended).
I used insulation from the basement.
7. Bottle of Heet.
You can also use denatured alcohol, everclear, or 91% isopropyl alcohol.
Step 2: Sand the Cans
Make it as smooth as possible to ensure a tight fit and prevent leaks.
You'll need to empty one of the cans, so go ahead and have a drink while you work on the second one. The second one needs to be full and sealed, so don't drink it yet!
Step 3: Cut the Cans
The cut needs to be almost perfectly even, so use a book to hold the blade while you press the can up against it and spin. You can also nail the blade to a block of wood.
Spin the can slowly while pressing against the blade, making sure not to dent the can in the process. It will take about 10 to 20 turns to cut through it enough to peel the two parts apart.
Then use the sandpaper to smooth out the cut edge.
Once you are satisfied with the result, use the second can to gently stretch the lip of the bottom of your stove. This will make it easier to put the halves together. Finally, put some fiberglass in the bottom half only.
Once the bottom is complete, make the top of the can the exact same way, but do not stretch the lip.
The fiberglass is optional, but important. It will prevent the fuel from leaking out while moving it around or while it's in use. It will also preserve unused fuel. Cotton balls will also work, so long as the inside of the can doesn't get hot enough to burn them - a possible concern during stove use or preheating.
Step 4: Put Them Together
Because the halves are pressure fit, you'll need to poke holes in the top to let the air escape. It just so happens that we need a filler hole anyway, so use the thumbtack to create one in the center.
Now carefully align the halves so the top fits inside the lip of the bottom. You'll probably have to use a shim made of left over can pieces.
Once they are aligned, squeeze the halves together as tight as you can, making sure to keep them even.
If you're having problems getting the halves together, use the sandpaper on the inside of the bottom half to remove a little of the aluminum. It also helps to smooth the cut edges of both halves to allow them to slide together easier.
Step 5: Make the Jet Holes
Use a thumbtack to poke a hole in a random spot around the edge of the can, make one directly across from it, then another in the middle of those two. Continue in this fashion until you have about 16 jet holes.
If you want a more efficient stove, use a medium sized needle for the holes instead of the thumbtack, and make more holes.
Step 6: Make the Pot Holder
The ideal height is about 1/2" to 1" above the height of the stove, or right at the tip of the flames. The flame height it determined by the type of fuel you use, and the size of the jet holes.
Make sure to sand off the coating before you use it. You don't want to breathe those fumes.
Step 7: Test It Out!
First, slowly fill the stove with Heet, allowing time for it to drip inside. It only takes about three tablespoons to boil a pot of water.
Once the fuel is inside, it's ready to light. Use a match or lighter under the bottom to preheat the stove. It only takes a few seconds. Once the can stove is too hot to hold, preheating is done.
Quickly run the lighter or match over the jet holes to ignite the alcohol fumes that should be coming out now. Alcohol burns very clean, so the flames will be hard to see in daylight.
Place the pot stand over the stove, and cook up some food!
You can blow out the flames if you need to, otherwise it will burn itself out. If you used fiberglass or cotton balls inside, there's no need to dump the excess fuel before storage.
You can use some tin foil around 90% of the bottom of the pan to create a wind shield that will also assist in keeping the heat on the bottom of your pan.
This Cool Little Miniature Stove is extremely durable, reusable and will be with you for a very long time. I've read stories of backpackers using the same stove for over 20 years!
Watch the video again for the complete process: