Rocket stoves are meant to burn quickly and extra hot. They use small twigs and sticks for fuel. So, when you want to use one, all you have to do is search the yard for a few dry sticks (an abundant renewable resource). There are many different designs, but they should have a few things in common: use small sticks for fuel, air flows to the fire from beneath the sticks, if it is insulated well (mine is not) then there should be little to no smoke, the heat is directed to a single point, the combination of rising heat and air from below makes a "rocket" sound.

These are my first prototypes.

The large one is made from 4in square steel tubing with 1/4in thick walls. It is all one piece and very heavy. It will be used for backyard cooking.

The small one is made from 3in square steel tubing with 1/4in thick walls. The burner grate is removable, as well as the legs and the wood/air divider. It will be taken to parks and camping for warm meals and coffee.

They both have a few layers of Rustoleum high-temp black spray paint. The paint is made for restoring grills and is rated for 1200 degrees Fahrenheit. It seems to be holding up just fine.

They are very sturdy, but heavy. Using thinner metal would have been better, but I used what I had. All the steel was scrap. They work pretty well and are fun to work with.

The night of filming was windy and 30 degrees Fahrenheit. It took awhile to get the fire started due to the wind, cold, and figuring out the first burn. Once the water was placed, it took about 10-12 min to boil.