by 4seasons » Mon May 26, 2014 3:18 pm
Over an hour into this experiment the J-tube finally ate as much fuel as the Batch box went thru in under 30 minutes.
Other things that I observed that are not in these videos:
1. J-tube is much easier to build as the mold is simpler to design and pack your mix around.
2. Batch Box is much more fragile with it's large roof on the firebox. I actually built the Batch 4 times before I found a way to keep the top from collapsing as soon as all the clay was dry.
3. Since I used the same amount of wood I would assume that the same amount of heat was released. The Batch just put it out over a much shorter period of time.
4. I can not speak to the efficiency of either design as I have no fancy testing equipment.
5. The J- tube core is actually pretty solid even when built from free materials. While I can't speak to the long term durability the J-tube has held up much better than the Batch in the short time I have played with them. I would think that a J-tube build like this encased in cob, indoors, and not abused would hold up very well. I would not recommend building a Batch Box using free materials for the firebox as it is just to fragile.