DIY Rocket Stoves

by Robert Wildwood

Rocket stoves focus a small amount of burning fuel to cook food. A handful of small twigs is sufficient to boil water. I have cooked with sticks while camping in the past, but the setup was not efficient, most of the heat spreading out in all directions. The rocket stove focuses the heat straight up to the stove top. Now we have a dual stick burner, no more spending money fuel! The energy of the sun stored up in small twigs is all we need.

Two rocket stoves.

These rocket stoveswerei made using large and small tin cans. The inside of the stove has an L shaped chimney which is surrounded by sand to insulate and focus the heat upwards to the stove top. The cracks in the tin are stuffed with clay so the sand wont leak out. A flat piece of tin laying in the bottom of the fire hole allows air to circulate from under the sticks and keeps the fire going hot. The tools i used to make these were a tin snip, screwdriver and sheet metal screws, and pliers.

Rocket stoves i made. Note the piece of tin inside the right stove for circulation.

November 2008: After taking these stoves down the Missouri River on our homemade pontoon boat, i have a good amount of experience with them. The type and size of wood you put in the stove makes all the difference. Drying the wood out in the sun and then keeping the wood in a sealed bucket to keep the moisture out of it is very important. Splitting the wood with a small hatchet or sharp knife is important too, split wood burns much better than the outside of round sticks, which are more fire resistant than the inside grain of wood.

It took awhile for the rocket stove to heat up, but once all the sand insulating the stove heated up, the stove was easier to keep going. Favorite thing to start a rocket stove with: wax cardboard, such as fruit often comes in at the grocery store. I also tore a small tube off our abandoned umbrella and we used this to blow thru, a bellows for the fire. Never quite as hot as a constantly burning conventional stove, but i think this is because of the ever present moisture in the air, permeating the sticks we cooked with.

In two months we never spent a dime on cooking fuel of any kind, and the wood burning rocket stove worked safely on an 8×20 foot boat with four people and a dog on it. I built a shroud around the stoves with flexible fresh willow boughs and some heavy canvas to direct the smoke away from the living space, which mostly worked.

On shore we usually dug a small channel in the sand and put a gril over the top of that with a fire below, easier to stick random wood into it and hotter than the rocket stoves. Ultimately, not as efficient in fuel consumption as the rocket stoves, but just the thing when you’re in a hurry to get some food. The rocket stoves required some patience.

Tin can rocket stove on our shanty boat, cooking sausage in a cast iron skillet, the Missouri River in the background.

Cooking with sticks. A very efficient stove. The choice of fuel is important, when i used old, dry, cured wood in Kansas City, it blazed and crackled like a rocket. All the wood on the river seemed slightly damp, even when bundled up and hung out to dry a day. Dry wood, because in that small burning chamber, there is no room for a fire big enuf to burn off the steam, it just chokes the fire.

Built this stove hood for the rocket stoves to keep the ashes and smoke from overwhelming us. Sticks and driftwood wrapped in canvas from a broken deck umbrella, a round opening out the back of it worked as a chimney, a curtain hung over the front helped to create the convection to suck the smoke out. The fire of the rocket stove was so small and focused, i never worried the hood would catch on fire, even tho made of cotton.