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Chris McClellan, AKA Uncle Mud, talks with Paul Wheaton about his visit to the labs and the experimental rocket mass heaters in the red cabin.

There is a need for documented experiments for small, lightweight RMHs for non concrete floors so we know what works and what doesn't. Pebble style benches are lighter than cob and when well designed with appropriate circulation are around 85% as efficient. The experimental cyclone built by Kirk Mobert revealed four problems and is to be scrapped.

1 - smoke out the front. blackening. unacceptable.This batch box has a slot at the back - shouldn't be lower than the door opening. tightly fitting door would help. too efficient at removing and storing heat, reducing draft. The riser was rebuilt with insulated firebrick but these are not problem free.
2 smoke at roof, unacceptable. if you see smoke, creosote is being made.
3 creosote layer inside bell.
4 fluctuating temperature in cabin. The cyclone is a RMH/masonry stove hybrid in a very small space. Burning for one hour overheats the cabin but it's cold by morning. A bench plus rocket would allow fine tuning to building and climate. It's beautiful, but not functional enough.

Casserole doors work on J-tubes but break on batch boxes - too hot at the front.
Paul wants the replacement RMH to have a pebble-style bench and 4 inch J-tube but with a full sized 48" riser, 16" full sized feed tube, final exhaust chimney kissing barrel to give heat to draw out cold plug. It's important to change only one thing at a time to prove if something works, not test 7 at once. Must be Gilligan proof - many people will stubbornly try to light them wrong.

Relevant Threads

Uncle Mud's Youtube channel
Uncle Mud's website

Uncle Mud Fall 2020 Fun at Wheaton Labs

tiny house rocket mass heater: the cyclone batch style

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Are there any build pictures of the new 4 inch system in the red cabin?
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Location: missoula, montana (zone 4)
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Since threads have gotten long, here is a post showing the RMH from Clayton: https://permies.com/t/128/139883/permaculture-projects/Clayton-Bootcamp-Experience#1152562 and from Dez: https://permies.com/t/35/146265/permaculture-projects/Dez-Bootcamp-Experience-BRK#1152417
Unofficial Companion Guide to the Rocket Oven DVD
will be released to subscribers in: soon!
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