Back in the seventies the Sotz company made kits where you could turn a 55 gallon drum into a wood stove.
You got a door, 4 legs, and a collar for the stove pipe.
You just got a jigsaw with a metal cutting blade, cut the holes for the door and the pipe, and bolted on the legs.
Then you painted the drum with high temp muffler paint.
The kit cost about $35. Sotz also sold the best wood splitter ever made, the Monster Maul. This giant maul had an all steel handle, and a 12 pound head. I still have my Monster Maul.
In 1975 I built a Sotz kit and what a wood heater that thing was. The firebox was 32 inches long and about 2 feet high. The air control was simple but it worked great.
You could get a hot bed of coals in your Sotz and then, you could put anything in there you wanted. You could load it up with 60 pounds of green, fresh split oak and it would burn all night. Easy to get a hot, 12 hour burn from a Sotz.
Sotz also made a kit for smaller drums, and in 1982 I built one of those, this kit had a round door.
That big Sotz was rated at 150,000 BTU.
I know of guys who have been running their Sotz for 30 years and the drums are still in good shape.
Sadly, when I moved from Georgia I left my Sotz stoves behind. The company went belly up in 1988. I did find a new-in-box Sotz kit for $60 a month ago on ebay, I was tempted to buy it. But, the fiancee hates the Sotz as much as I love it and it is no-go. I gotta spend $2200 for a new Jotul for the new home.