Cut a hole 4 inches in diameter in the side of the large can, with the bottom of the hole 2 inches from the bottom edge of the can. Using the 40 oz. can as a template, draw the hole with a permanent marker, then carefully cut out with tin snips.
Insert the duct elbow through the hole from the inside so that approximately 2 inches of one end is sticking through the front. The other end of the elbow should point upwards towards the top of the can and be relatively centered inside. Place a stone or piece of brick underneath the elbow to support it from the bottom of the can for stability.
Fill the body of the large can on the outside of the duct elbow with insulating material, such as vermiculite, perlite or sand, until it's within 1 inch of the top of the duct elbow.
Cut another hole 4 inches in diameter in the middle of the large can lid and place over the top of the duct elbow, until the lid rests on the insulating material.
Cut the bottom out of the 40 oz. can. Slide this can over the horizontal end of the duct elbow until snug.
Gather your fuel source. The rocket stove burns very efficiently on twigs and small pieces of scrap wood. Light a few twigs and feed the wood through the front can until the fire is burning at the curve of the duct elbow. Continue to feed slowly to keep the fire at a steady level. Set a grill over the top of the rocket stove and place the cooking pot on top of it.
Things You Will Need
- Large metal can (with lid)
- 40 oz. can (with 4-inch opening)
- Metal duct elbow (4-inch opening)
- Tin snips
- Insulating material
- To cook a whole meal at once, make two rocket stoves.