Thank you everyone! Such cool info and perspectives!
Glenn Herbert wrote:...RMHs are commonly built with free local or recycled/scrounged materials, but can be built of masonry the same as a traditional style heater...
You were the first to say it on this thread, and I think this is the most important difference! I think the real innovation of the RocketMH is **the ability to do it yourself cheaply**, which makes them **economically democratic*. My lightly educated guess is the availability of modern ducting and barrels (a global supply chain container) allowed a redesign with horizontal runs and cheap materials that would not have been feasible or practical a couple centuries ago when the first ones were made. The science and the method are not new, but the DIY with found materials method DEFINITELY is new. The horizontal runs in particular which would have required many skilled steps, and likely difficult-to-find high quality clay centuries ago, are literally a snap of the fingers with mass-produced ducting/pipes. The less important differences are the RuMH is built to last, and has some legit aesthetic advantages. But the CO$T of them!!! 😲
Having been to rural arctic Finland and seen some of the handmade Finnish batch burn/mass heaters, I know the designs are all over the place, and they are not all made of the same materials, and some of them appear to have horizontal runs (although I couldn't see inside, so...) I also believe (I didn't say know) the RusMH are burning wood gas, because without that, these things (which cannot be disassembled and cleaned) would fill with creosote and catch on fire. The one thing I can say with confidence, is the pictures I find online of RusMH, and what I saw in person are a different - but I am hardly an expert. I have never been to Sweden, or Russia. I have four brick and stone masons in my family, but I have never owned either a RoMH or a RuMH.
A fun fact I learned over there is the Sami are the last native peoples using some traditional skills in Europe. The rest of them just asimilated modern ways as they came around, and lost that identity. Being part Native American, that blew my mind.
