A heater made out of a 55-gallon barrel can be an economical way to heat a large space, such as a shop or garage. You will need some skill and tools, such as a welder and air chisel, to accomplish this project. A kit makes the process smooth and easy.
Find a Barrel
A heavy-walled, 55-gallon steel barrel is most suited to being turned into a woodburning stove. Older barrels are made of heavier steel than newer ones. Check the barrel for rust and corrosion. The barrel needs to be solid. Pay special attention to the bottom. Make sure it is clean and that it did not contain combustible materials. It needs to have a lid that fits with the bungs intact.
Buy a Kit
If you decide to build a woodburning stove out of a 55-gallon barrel, the easiest way to make the conversion is to buy a kit. The kit includes a door, chimney piece and instructions for using them. Some may also include legs. The kit should come with instructions and warnings that you should follow exactly.
Legs will add stability to the stove and keep it off the floor. One-inch diameter pipe is a suitable material that is easy to work with and easy to find, but whatever you decide to use, the legs need to be metal. You can weld a frame with all four legs attached, then bolt that frame to the barrel. If all four legs are connected, it will be easier to make it stable. If you put the legs on before you cut the holes for the door and chimney, it will keep the barrel from rolling and you'll find it easier to make the cuts.
Some kits come with legs. Follow the directions for attaching those.
Install the Door
Decide which end to put the door on. It's often easier to put the door in the bottom end, because the bungs can get in the way on the top end. Make a template from the door piece of the kit you bought. Trace the template onto the barrel end and cut it out with a tool. An air chisel or reciprocating saw is best because it will cut without sparks, reducing the risk of combustion or fire. An air chisel is a relatively inexpensive tool that makes a clean cut, so it's easier to fit the door. Make sure you don't cut the hole too big.
Install the Chimney
The chimney will go in the opposite end (the back) of the barrel, on the top, when the barrel is lying on its legs. The kit should come with a template for the chimney too. Cut a hole for the chimney the same way you did for the door. Make sure you don't cut the hole too big.
The final step before installing the stove is to bolt the chimney and door into place. Follow the instructions that come with the kit. You will need to put in additional chimney pipe and figure out how to vent it.
Down the Road
These woodburning stoves don't last forever. They will burn out. When the barrel burns out you can use the same kit pieces to build another stove with a new barrel.