Cut three semicircular draft holes in the bottom of can 1. Punch several holes in can 2, which is where the fire burns. Then, supporting it from inside with a block of wood, cut three slots in the bottom to act as "fire bars." Suspend can 2, slots at the bottom, inside can 1 with a piece of wire.

Cut three vent holes in the body of can 3, and then cut out the bottom. This will give you three "ears" that are bent down and snap over the top of can 1.

To light the stove, build a fire in can 2, gradually feeding twigs or chips through the vents of can 3 (or remove can 2 and feed the fire from the top).