Saturday, 5 January 2013

Rocket stove

 
These seem to be all the rage at the moment so I thought I'd have a crack at making one. It's basically just cooking over a chimney but is meant to use less fuel than an open fire.

Starting with an old five gallon cooking oil drum...


...cutting the top off:


Chimney parts from old stove pipe cut to size and ready to assemble:


The chimney will be joined like this inside the stove:


Parts assembled and drum insulated with sand:


Fire started:


Sticks are then fed in at the bottom on a bit of metal shaped to fit inside the chute:


Kettle on, job done:


11 comments:

  1. Sand is a poor insulater. Generally, the lighter the material, the better insulation quality and efficiency of the stove

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  2. Simon, thanks for posting this.

    Any chance of some assessment of its performance such as: efficiency (e.g. wood usage vs time to boil); smoke; size of fuel that it works best with, etc.?

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  3. Aprovecho here in Cottage Grove, Or came up with rocket stove design and now has a testing lab. I've made a couple of their smaller designs using a gallon number 10 can and a couple of bean cans. Nice light size for backpacking.

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  4. Hi Gordon, I've found it does use wood more efficiently as the way it's fed in means you just burn the sticks a bit at a time; I feed in sticks about 1 inch thick or a bit more once it's going; it's probably not much less smokey than an open fire using similar size wood; I havn't timed how long it takes to boil but on videos I've seen on youtube they work at best efficiency if the pot/kettle fits just inside the opening (unlike mine) so that heat goes up the sides as well as the bottom. Hope this helps.
    Simon

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  5. A good insulator is perlite. I've used it to make a little smelter of a similar design.

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  6. That´s a good idea for a gallon can and tubes, insulation is good for those cold days... another idea is to dock 1 and half cans: one to keep the heat (TOP can be used as oven) and 1/4 (middle) for burning wood this part can have a little door with some holes to allow air flow and 1/4 (bottom) for ashes :)

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  7. Sand may not be the best insulator, but good luck searching for better one on camping site. IMO heat loss won't be noticeable in this use mode.

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  8. Could try rockwool insulations, Roxul has an insulation that is about fire proof to 2150f degrees or such.
    http://www.roxul.com/residential/residential+overview

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  9. Looks very similar to a casting furnace. If you use refractory sand you might make it even more efficient.

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  10. Most rockestoves use sand, cement, brick, rock, concrete, mud, adobe, etc to put a large thermal mass for long term thermal stability. ... Yes, it an be used to cook or boil water, but I have seen them use mainly to heat huts, benches, or gereenhouses. The seem to be pretty efficient and take little fuel for the heat recovered.

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