This project goes over the build of an efficient clean burn multi-use ammo can portable rocket stove. Easy to build, small, portable, and leaves no smoke. The reason it is smokeless is that it uses a secondary burn system. Also can be used as a cooking stove.
STEP 1 : REPLACING THE RUBBER SEAL
The first thing you need is an old NATO ammo can. Remove the rubber seal that sits around the top of the can and replace it with a stove rope. The stove rope gets compressed when you close the stove with its closing mechanism and the smoke won’t escape from around there.
STEP 2 : MAKING A HOLE FOR THE FLUE PIPE
On the top, we have the flue made out of the 2-inch stainless pipe. It has two sections, the upper section slides onto the lower section. In order to build the flue, we take the top of the ammo can, then place the pipe on top and draw around it that gives the circumference. Take a grinder and simply cut across the shape.
In order to get a smoke-tight seal, we wrap some stove rope around the flue area we just cut and then insert the pipe and use a jubilee clip around the bottom and compress it against the stove rope.
Once this gets up to working temperature, it draws cold air in from down below and expels it out at the top. So all the smoke from the stove gets drawn upwards.
STEP 3 : STOVE DOOR MECHANISM
We use 2 turnbuckles as a stove door closing mechanism. There are two closing mechanisms on this door. One is a quarter-turn latch. So you rotate it, the door opens, you close and then you rotate it and it locks the door closed. Another mechanism is using a long piece of metal. You can turn each of these a quarter turn and that locks the door extremely tight to fit these turnbuckles.
STEP 4 : BAFFLE PLATE FOR MORE HEAT
The stove baffle plate is made out of 0.8mm thick thin steel. To make it, measure it up against the stove and bent the steel into that shape. The baffle helps in generating more heat as it keeps the air from escaping the burn chamber.
STEP 5 : ADDING A SECONDARY PIPE
A secondary pipe made of galvanized steel pipe comes from the back of the stove and comes across the stove through a small hole. The pipe has been drilled with small holes. When the stove is in operation, this draws in cold air from outside, it gets pre-heated on the way down across the burn chamber. And then the pre-heated air rises and is expelled naturally through these holes.
And since this pipe is just under the baffle plate, it reignites the smoke and the smoke is burnt on the way across the upper section of the stove.
STEP 6 : INSULATING THE STOVE
The stove is insulated using fiberglass and stainless steel from three sides inside helps in the efficient secondary burn. You just need enough insulation to get the temperature high enough to get secondary burn. If the whole stove is insulated then the heat would dissipate through the flue instead.
The bottom of the stove is insulated using half-inch Rockwool and on top, we have some chicken wire that stops the burning fuel from sitting on the bottom of the stove and being starved of oxygen. It allows the oxygen to get underneath and burn all the way around the wood efficiently.
The primary air is drawn in through an air intake at the side of the stove. To attach it to the stove, bend the pipe around the side and place a jubilee clip and stove rope around to insulate it. So when the stove is in operation, you can add sticks, twigs, pellets or anything you want without opening the door.
Image Credits : Christopher Barr – Random Chris