[Cob] re: two chamber earth oven question

[Peter Ellis]

Amanda and Ray, thanks for your responses.

Ray, I appreciate the invitation, but I'm in Joisey.  The spiral wrapping of 
the chimney on your pizza oven is interesting.  I had already been 
considering taking a page from the heated cob bench and possibly running the 
flue around inside the cob walls of the oven.

Amanda, I don't have any drawings as of yet, but I expect I will take some 
photos of the process when I build the oven, in about two weeks.  I'll see 
what I can do about posting those, and perhaps the ones of last year's 
single chamber as well.

In the absence of pictures, let me try and describe the idea in text.  My 
oven goes on a set of sturdy sawhorses (it's a temporary installation for 
two weeks in August), so I don't have a foundation in a conventional sense.  
What I'm planning right now is to build a cob rocket stove at a height of 
about 2 feet above the ground, probably on some cinderblocks.  The chimney 
of the stove will rise up to the height of the oven and go through the oven 
wall, so the hot gases from the stove swirl about inside the oven and heat 
it before venting out the oven mouth (just as they do when the fire is in 
the oven).

This particular setup has the risk of being rather fragile, what with a sort 
of "freestanding" chimney between stove and oven.  OTOH, it's an experiment 
that doesn't have to work for very long, and if the rocket stove part fails 
I can always patch that hole up and just use the oven as a single chamber.

I have in mind building a permanent installation at my home, and possibly 
using two rocket stoves, venting into opposite sides of the oven.  Seems to 
me that might help get to an even heat a bit faster.  In a permanent 
installation the stoves would be integral to the foundation of the oven 
structure.

Peter