I stumbled across the
rocket stove on one of the many outdoor/survival skill websites I frequent. The stove has several advantages over an open fire when it comes to cooking. The two major benefits are less fuel is needed and less smoke is produced.
After dreaming about it two nights in a row, I figured I better make one!
I gathered all the materials and tools I needed. I didn't end up using the small soup can or the wood chips (more on that later). Also I used another pair of snips and work gloves after I cut myself on the metal.
I cut out a soup can sized hole in the side of one large and one small coffee can. After removing the remaing end of the soup can I inserted it through the holes in the cans. I filled the space between the coffee cans with insulation. The idea is to keep all the heat in the cylinder and ultimately directed up to the cooking vessel. This is something you can't do well with a normal fire pit.
Ideally I would have used wood ash from a fire. Unfortunately I don't have a fire pit anymore so I had no wood ash. I opted for flammable wood chips! I reasoned that they wouldn't be touching flame and there wouldn't be enough oxygen to ignite. As it turned out I was wrong. During my first test they did burn. I doused the whole thing with water before it got out of hand. I had to settle for sand as my insulator which isn't very good since there aren't many pockets of are between particles. When I find wood ash, I'll swap.
I used the bottom of the other large coffee can to make a cover to hold the insulation in. I also decided to leave four tabs sticking up to give the cooking vessel something to sit on.
The soup can has a platform in it. The fuel goes on the platform leaving the bottom half open for oxygen to enter. By only burning the tips of the wood, less smoke is produced. As the wood burns down, it is pushed further into the stove.
Here you can see the pot resting on the tabs.
I tested the stove by bringing one quart of water to boil using only the tinder and wood pictured below.
It took 10 minutes although I let the fire die a little so in theory it could have boiled faster. As you can see in the picture below I didn't need all the wood.
To increase the efficiency of the stove I could add a skirt around the pot that would direct hot air up the sides of the pot. The sides of the stove were hot to the touch so thicker insulation would also be an improvement. That would require a larger can though.
While not a primitive tool, this stove is pretty cool and very practical in an urban survival situation. With proper ventilation this could be used indoors due to the low level of harmful emissions.
There are some good how-to videos with various size stoves if you search Google Video.
