Planning a RMH using a big oil storage tank as the drum. Like a monster one... So the kusnetxov site is really intriguing, but I've not actually talked to anyone who has built a double-bell. It seems to make sense, but there have been enough rocketish stove failures/weak smokies built at my farm already. Also check out our youtube video "The Dome that ate a Rocket Stove"
Do the next thing next. That's a pretty good rule. Read the tiny ad, that's a pretty good rule, too.
It's like being on a deserted island - only with gardens and natural buildings in Montana