The rocket stove was developed in the 1980s to be a portable and fuel-efficient cooking stove. Using a rocket stove creates less smoke and emissions, making them more environmentally friendly than most camping stoves. They are inexpensive and fairly easy to make. Rocket stoves are composed of only four major parts and burn solid fuels such as twigs or charcoal, so they are easy to maintain.
Cut a hole in the side of the large can the same diameter as the small can with the tin snips. The large can should be at least as large as a Number 10. Both cans should be thick-walled tin or steel. Cut off both ends of the small can.
Slide the smaller can into the hole until it is about a quarter of the way through the larger can. Seal the gaps between the two cans with clay or weld them shut. Clay is easier and works well but deteriorates quickly.
Fill the bottom of the large can with sand until it reaches the bottom edge of the small can. If the can is large enough, the inside walls can be lined with bricks. Place the end pieces that were cut from the small can on the sand to use as a fuel platform.
Optionally, a small hole opposite the small can could be added to allow for a little more air flow. This is more useful when constructing small rocket stoves.
Place fuel, like twigs or small pieces of wood, into the small can with the ends extending into the large can. Do not overfill the small can--there needs to be enough room for air to flow through. Light the ends of the fuel that are inside the large can; do not light the fuel in the middle.
A pot skirt will improve the efficiency of a rocket stove.