Last year I came across the idea of a sawdust wood stove. The stoves are versatile and can be sized according to your needs. The wider the stove, the longer it will burn. A stove in a 55 gallon drum usually burns for about 12 hours. The taller the stove, the more heat it will put out. If you don’t need a hot fire, you can load the stove half full for a smaller fire.
It was different, simple, and seemed practical so I just had to build one. While I was scrounging the stuff for the full size stove, I tested the concept on a small scale.
These are the main parts that go into the sawdust stove. The large can on the left is the outer can. It has a chimney hole cut toward the top, and an air vent cut toward the bottom. The blue can has a hole cut in the center of the bottom. Both cans have three legs. The cap fits over the outer can.
The cans assembled look like this. The white pipe is a piece of PEX pipe used to create a chimney when the sawdust is added. There is about a 1 inch gap below the bottom of the inner can and the outer can.
The sawdust is loaded in the inner can and tamped around the pipe. It’s important to pack the sawdust tightly to keep it from collapsing when the pipe is removed.
Sprinkle dirt or ashes on top of the sawdust to keep it from catching fire. The sawdust should only burn around the hole in the center.
Carefully remove the pipe by twisting back and forth and slowly pulling it out. Lightly round the edges of the hole to keep them from collapsing. Place a folded strip of paper in the hole, being sure not to collapse the sawdust. This will act as a wick to light the sawdust.
Light another strip of paper and stick it through the air vent to light the wick.
The door swings to change the amount of airflow. More air allows a faster, hotter burn. Less air slows the fire down.
When the wick is burning well, put the lid on.
After 20 minutes the sawdust was smoldering nicely and putting off quite a bit of heat.
An hour into the test, the sawdust had started to settle. It was burning very cleanly with no smoke. It put off a surprising amount of heat for the size of the stove and the lack of flame. The sides of the stove were very warm and the top was too hot to touch.
After 3 hours, all that was left was a small pile of smoldering sawdust. This continued to smolder until all that was left was a dusting of powder.
My big stove was built using a 55 gallon drum and a low boy water heater tank.
This is the water that drained out of the tank. Makes you think twice about drinking tap water, doesn’t it?
After I cut the top of the tank off, I found that the bottom of the tank had about 6 gallons of hard water build up. After cleaning it out, I drilled a 2 inch hole in the bottom of the tank and welded 3 short pieces of angle to the sides for legs.
Since this stove is too big to disassemble to clean ashes out, I put an ash tray in the bottom of the outer barrel. This also simplifies lighting the stove. Just build a fire on the end of the tray and slide it in under the inner barrel. The tray from the lid to a washing machine and an element cover from the water heater.
The tray takes the place of the air vent on the mini sawdust stove. Slide it in or out to control airflow.
I’m ashamed to say I never used the big sawdust stove. Through a series of events I ended up with a big pile of firewood so I dragged the regular wood stove into the garage. It doesn’t have the light-it-and-forget-it convenience of the sawdust stove, but it suits my purposes well enough.
Today I took the inner barrel out of the sawdust stove to convert into a chicken scalder. The legs were such a tight fit that to get it in the 55 gallon drum in the first place I had to jump up and down in the inner barrel. It wasn’t a lot of fun getting it back out. I’m glad Bethany wasn’t around with the camera!
If I ever run a sawmill or do a lot of woodworking I’ll probably build another sawdust stove. Until then, the miniature version will sit on a shelf in the shop as a great conversation piece.
Any idea on what to do with the 55 gallon drum with holes cut in it?