Tuesday, December 28, 2010

Guest Post: DIY Wood Gasification Stove, by Valcas1

This guest post is by Valcas1. He has done an amazing job creating a functioning wood gasification stove for almost no cost. The moment I saw it, I knew that I wanted to put it up as a guest post, and Valcas1 thankfully agreed. 

For those who are not familiar with this type of stove, a wood gasification stove is different from a fire or a wood burning stove in that this type of stove heats up the wood in such a way that instead of producing smoke, the wood turns into charcoal while emitting flammable fumes. Those fumes are channeled away, and then burned at the top of the stove providing for a clean burn.

I bought a 1qt paint can from my local Ace hardware. $1.99 this one happened to be unlined which is what you want. If you can only get the epoxy lined ones just make sure you burn it real good before cooking.

This is not my idea but I was told that a Progresso soup can will by friction into the inner lip of the paint can. So a can of Chickarina soup was in order for lunch and I now have this.

I cut the bottom of the paint can out with a regular hand held can opener. Some online research says use a safety cutter but I didn't. I think the only benefit from using a safety cutter is you get a bottom that can be put down as to not scorch the ground. Now we have to put holes around the top to allow for the draft between the two cans.I used a Irwin step drill bit as seen is this picture.

You can see how I laid out by vent holes on a piece of paper aand simply taped it to the can as a guide. I went with holes around the top of 3/8" about 1" apart on center.

I am sorry I dont have pictures of this step but you need to put a second series of holes around the base of the inner can. I again used 3/8" and drilled them low on the can. Now take your paint can that you have cut the bottom out and drill 1/2" holes around the base so that you can draw air in and up the side walls between the cans. I started with 4. I figured you can always drill more if needed. I am still trying to fine tune this part.Now press you inner can into the inner lip of your paint can from below. It is a perfect fit and will take some pressure to get the inner soup can to seat well.Looking into the the cans it will look like this.

In the last picture you can see the 1/2" hardware mesh fire grate I made to lift the bottom of my wood off the bottom of the can and over the top of the lower holes. Final picture is of the stove after several burns. I am experimenting with different pot stands now and will update my findings as I progress.

These stoves are designed to burn from the top down so I figured I would show you how I set mine up to light and make some boiled water. First here is my fuel. As you can see it isn't much more than twigs and pencil sized sticks. There were four small pieces of wood that were thumb sized I put in first.

Fully loaded and a few slivers of fatwood for starting.

Starting to burn.

...good burn going now.

No smoke, but lots of heat for that little bit of wood.

Not sure if you can see how it is burning the wood gas in this picture I tried to show it but not sure if I pulled it off.

Cool enough after burning for 15 mintues to do this.

Ended up with this.