I just made a downdraft gasifier wood stove. That means gases burn as they get sucked through the bottom and out the inner wall vents, utilizing what scientists call the “downdraft gasification” effect. I based it on the Bushbuddy backpacking stove. Except that costs 100 dollars and mine was free and made of all recycled materials.
I love having a regular fire but sometimes that wont work. This stove uses less wood, burns more efficiently and hotter, leaves behind only ash instead of charred wood and coal, and produces very little smoke as long as you keep it going hot.
So that means you can still use wood fire to cook in parks that don’t allow open campfires (leave no trace rules), when you cant find a lot of wood to burn, or when you squat public or private property and cant make much smoke.
Materials:
1 progresso soup can
1 sliced peaches can
1 metal clothes hanger
The soup can forms the outer wall, so it gets vent hole drilled along the bottom of the sides of the can.
Cut a straight piece of wire from a clothes hanger and drill holes so the pin will go across above the outer wall’s vents. This keeps the inner wall from sitting on the bottom of the outer wall.
The peach can forms the inner wall, so the bottom of it is drilled a ton of times to make it a vent (the bushbuddy uses a mesh bottom), it gets the top cut into three prongs to form the pot stand, and it gets vent holes drilled on its walls where they sit inside the outer wall, near the top.
inner wall and pin removed to show pieces
Inner can inverted with pin inside for storage. You can see how i made the bottom into a vent. I think making the wall-vents bigger and the bottom even more ventilated might make the stove more efficient. I dont know for sure.
Probably much room for design improvement, but the stove boiled water easily with just a couple little branches for fuel and I made some hot cocoa. ;D