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Mobile rocket stove to test?

Posts: 21
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Hi new here and been studying the forums a while.

We are studying the rocket stove vs masonry heaters for our large but reasonably well insulated house. We have been using a regular wood stove for several years with a triple insulated flue that goes through the ceiling. We ran across a picture of a rocket stove made in an old cattle trough by Matt Walker and are considering building one to get a feel for one and try as a side by side comparison with what we have. If it works for us, then we could build something more attractive and permanent.


Suggestions on parts that will be efficient enough to perhaps reuse in a permanent design?
Suggestions on parts that are easy to find and put together?
We have metal barrels, cattle troughs and access to clay soil. Sand and Gravel isn't too hard to obtain
Looking for clay chimney liner as that seemed an easy way to make the J tube part, or is it?

Also I read the following on the Unforgettable Fire site and am not sure I understand. Is this just marketing mumbo jumbo or is a "gassifier" more efficient/use less wood for the same heat?

"How Is A Gasifier Stove Different From A Rocket Stove?

The Kimberly™ stove and the Katydid™ stove are gasifier wood stoves, not rocket stoves.

When a Kimberly™ or Katydid™ wood stove is dampered down, the fuel maintains an approximate 450-degree Fahrenheit temperature as it burns, thus creating massive amounts of smoky gases. As the smokey gases rise to the top of the combustion chamber in our Kimberly™ or Katydid™ wood stoves, the gasses ignite and burn at a very high temperature.

The bulk of the heat produced in our Kimberly™ and Katydid wood stoves comes from the secondary combustion process, which produces a very efficient and clean burn, with very little smoke emitting from the chimney.

On the other hand, while rocket stoves burn very hot and very clean, they are not efficient. Rocket stoves are hungry and consume lots of fuel."

Posts: 245
Location: near Houston, TX; zone 8b
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On the other hand, while rocket stoves burn very hot and very clean, they are not efficient. Rocket stoves are hungry and consume lots of fuel."

If Kimberly stoves were so efficient, they would include a graph from a Testo 330 gas analyzer (or something similar) on their website; do they? They are really nice looking. It is also interesting that Kimberly is even comparing themselves to a rocket stove.

It would not be possible to burn clean and not efficiently. Burning fast and hot necessarily make the burn more efficient. What this person may be referring to is that a j-tube design creates a lot of heat, so you need to store it somewhere or your living environment will alternate between too hot and too cold as a cast iron stove does.

There lies the intersection of the rocket mass heater and masonry heater. Both of them have relatively small combustion areas and a large mass in which to store the heat.

Building a rocket design with a lot of metal parts would not tell you whether you would like a rocket mass heater in your house. Metal does not have good thermal storage characteristics.

People who have rocket mass heaters in their living quarters (including me) are very happy with how much heat they get for the amount of wood consumed.
Posts: 236
Location: Seattle, WA
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You should be comparing rocket mass heaters to masonry heaters, not rocket stoves. There is a difference!

Rocket mass heaters take the rocket stove concept and harness the fact that the burn hot and fast to their advantage. In a RMH, the exhaust coming out of your chimney should be far lower temperature and with far less smoke than either a traditional wood stove or a masonry heater. That tells you the efficiency of the system right there. I think if you were to compare a RMH to one of those Kimberly or Katydid wood stoves, it wouldn't even be a competition.

I'd go ahead and build a test stove. My main advice is that if this is your first RHM and you are building an untested design or designing it your self, don't get discouraged if it doesn't work out. If you can, it would really help to build a time tested design the first time. It really doesn't take that much more time or materials and your results will be much, much better. Ocne you've got that under your belt, then experiment!
It's feeding time! Give me the food you were going to give to this tiny ad:
Rocket Mass Heater Plans - now free for a while
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