Encasing/partially covering combustion chamber with cob

From "the book":

"If radiant heat is prevented from escaping from the barrel, more heat will flow into storage. Part or all of the barrel can be encased in cob, and/or the barrel could be replaced by cob or brickwork. Thus, a bigger proportion of your heat will be available for storage and contact heat. You may want to size storage and the length of buried flue with that in mind."

Has anyone actually tried this? Either actually building the combustion chamber out of cob/material other than the steel drum? Or building a cob unit on a side of the steel drum?

I am curious about the possibility of building a cob oven onto the side of the combustion chamber that would use/capture radiant heat from the side of the barrel? Any thoughts on this or what the temperature would be like in that situation?

Robert Woden : Part of the Miracle that occurs when the hot exhaust gases cool, shrink, become denser and heavier, is then they flow 40 + feet horizontally
through our Cob Thermal Bench, giving up most of their remaining heat energy to the Thermal Mass !

Some people who post to these threads are able to prove Mathematically that the energy radiated off of the barrel is the work energy that must be expended
to make our rocket work like this ! I am not one of those people, so I must rely on faith and observation !

There has to be a difference In the amount of heat energy measured by Temperature between both sides of the barrel, While the entire barrel can be cob covered,
tiled, painted, or surrounded by a lattice of brick there is a minimum amount of heat energy that must be radiated off of the barrel to work, too much cob, too high,
or too thick will prevent this from happening !

We also need to protect the difference in Temperatures between the inside of the Heat Riser and the outside, that is why we wrap insulation around the outside of
the Heat Riser Inside the Drum !

The area that most of us call the combustion chamber The Burn Tunnel and most of the Hear Riser is never called the Combustion Chamber in the book (I THINK).
As such they are Universally made out of brick or cob ! I can easily see where this has caused confusion ! Generally I refer to everything that is not part of the
Horizontal Chimney, or Thermal Mass as the Rocket burner, and speck of the Combustion Chamber or its parts by name and usually this allows me to be
understood !

With over ~100,000~ Rocket Mass Heaters RMHs built word Wide, it is not surprising that we have some problem with the way regionalisms sneak into our words!

Some birds wings you just can't clip ! Ernie and Erica Wisner our Moderators in these Forum/Threads have an RMH build that includes a Rumford fireplace and a cob
oven that works! As their personal schedule keeps them very busy, and Moderator dyes and Writing takes away additional time (Ernie Wisner is building a Deep
Water Ship for their future travels ) You should check out their site Ernieanderica.info Big AL

Late note : You may learn something from the troubles at Basement RMH Over in The Wood Burning Stoves Forum Threads ! A.L.

I have covered my metal drum with claymud no organic matter. Works well I haves short bench and it seems to work great.