Real quick, Im still very new to the site but love all of the information. I am into the idea of lightnening my load however I am most interested in making gear. I am Looking at woodgas stoves and really am wondering a few things. I have read quite a bit on the subject but it seems to go from people experimenting to science beyond my comprehension.

Sorry accidental post....anyway, is there a minimum volume of combustion chamber i should look for, also what is a desired space between the inner burner and outer shell, does it depend on volume?

SO I just decided to build and experiment. I used 2 soup cans, the small inner can is of the condensed variety, and the outer is the no water added kind. Drilled and cut some holes and wound up with this.



I am working on a pot stand, probably the mesh variety,at which point I can get some boil times.

The weight is 4 ounces right now without a windscreen.

I suppose there is a limit on the lower end. IE it needs to get hot enough to light off
without a ton of starter fuel.

I would also imagine that there is a ratio of diameter to height to material to chamber etc that would work best.

That said I built one out of a sardine can inside a 12oz Heineken can and that worked. Would burn about 20 minutes. Hard to light though.

They are fun to play with but I think an Alcohol setup is smaller lighter and easier and does not smoke your pot. I will mention that for 20-30+ odd years I just cooked on a fire and carried a small stove as a backup or if I did not feel like starting a fire.

This subject has been discussed pretty extensively in the past couple of weeks.

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=58262

http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=58682

In summary, tin can "wood gas" stoves are really poor examples of biomass gassifiers. A true biomass gassifer produces a clean blue flame. In WWII biomass gassifiers were put in the trunks of cars to save gas and diesel for the war effort, and some people even today still choose to run their cars on wood.
http://www.impactlab.net/2011/05/20/wood-gas-vehicles-firewood-in-the-fuel-tank/



Dan Yeruski has done some comparisons between tin can, double wall, "wood gas" stoves and single wall top lit up draft (TLUD) wood stoves and found there's no improvement with the double wall arrangement. I haven't done any comparisons myself, but I would agree with his observations, since most of the stoves on youtube claiming to be "wood gas" stoves are really, really, poorly built and perform very poorly. They might burn a little cleaner than a normal hobo stove, producing slightly less smoke.

To have a good clean burning wood gas stove, there needs to be proper fuel selection, preparation, loading, etc..., and a really well designed stove for there to be any benefit. And in the end, a true wood gas burner is far more finicky and complicated to use than a normal wood fire or TLUD burner.

For me, playing with the idea of a small burner that produces a clean blue flame is a fun hobby, but as a backpacking stove- get a back-country boiler, trail designs tri-ti (ti-tri? I can't ever remember) or one of those collapsible box deals. I may eventually bring my wood gas stove to play with on the trail, but I wouldn't leave my alky setup at home.

BM

I used an artilce on this site that came out a couple of years ago to build this one. It gets quite a bit of use, both with wood and a Trangia burner that fits in the top.