A rocket stove has many advantages over a propane stove or grill for survival needs. Fuel for a propane stove or grill may become scarce and difficult to find during hard times. A rocket stove burns small pieces of dry wood such as twigs, small tree branches and pieces of scrap wood. A rocket stove can be built small and is very portable to take with you.
The design of a rocket stove increases the oxygen to flame ratio which burns wood with a concentrated high heat factor with little smoke. They are easily lit and keep burning even in windy conditions.
I built a long-lasting and durable rocket stove from a paint can, Plaster of Paris, sand and a smaller can such as one used for canned vegetables. With a few simple steps the outcome was a portable rocket stove for cooking. With added oxygen, temperatures can get hot enough to be used as a forge to heat iron and melt aluminum and lead.
Begin by removing the label from a metal paint can and trace a template of the small can diameter onto the side of the can. Next, with an awl and heavy-duty cutting shears remove the circle template on the paint can so that the small can fits tightly into the hole.
Use another can, larger in diameter and taller as a form for the flue. This can will be removed during the cementing process. Cut one side of the smaller can to fit flush against the larger can.
Insert and center the larger can (flue form) into the paint can. Push the smaller can with trimmed end through the hole and push it snugly up against the flue form. Make sure the flue form stays centered and there are no gaps between the two cans.
Mix a small batch of 2 parts Plaster of Paris to one part of clean sand into a thick, slightly wet mixture. Begin by spooning the cement mixture into the paint can around the flue form and inserted can. Gently tap the paint can to fill in gaps and to remove air pockets. Fill to the top of the inserted can. Once the cement mixture begins to set, gently twist the flue form both clock-wise and counter clock-wise while slowly pulling straight up until flue form is above the top of the paint can.This will loosen the form for easy removal.
Continue adding cement mixture until paint can is filled 1/2 an inch below the rim. Once again, gently tap the paint can for settling. Once the cement mixture begins to set twist the flue form and slowly pull it straight up from the still wet cement mixture and remove it completely. With the back of a wet spoon, smooth out the cemented edges and cavity of the cement flue. Let your rocket stove / forge cure completely for at least 48 hours before firing it up. For added air flow, poke holes with awl around the top rim of the paint can.
To use the rocket stove as a cook stove simply light tinder and twigs and feed it through the small can (feeder) into the cemented fire flue. Slowly add larger pieces of wood to build the fire and heat. Turn your rocket stove so the wind blows in through the (feeder) creating a draft, adding oxygen to the flame increasing heat intensity with very little smoke. When cooking place spacers (rocks, metal, or copper tubing) on the top rim of the rocket stove between stove and cooking pan to allow air flow.
To forge metal, you will need to increase a consistent air flow and use longer burning materials such as charcoal briquettes or hardwood coals. A hose from a small wet/dry vacuum with air blowing out (not in) aimed into the feeder works great. A hand pumped bellows or foot operated air pump also works well, however,with a bit more physical effort. Done properly the temperature will be hot enough to heat and bend thinner pieces of iron (nails and rods), harden (temper) thin steel for blades, or melt aluminum and lead to make various castings.
This version of a rocket stove is very durable. It’s compact and though too heavy for packing on your back it is very portable to take along on picnics, camping or to your bug out location.
Take a baby step and build a fuel efficient and nearly smokeless rocket stove / forge for your every day or survival needs.