Alaska McCoy

Will do.  I will try to take pictures and use bolt-together flange fittings where i can.  My goal will be to have something robust and gas tight with as little welding as possible.  It will also be somewhat portable that way.  It should also be easier to fabricate so if someone doesn't have welding skills they can have it made relatively cheaply by a welding shop.  Nice thing about oil pipe is that the flanges are all standard fittings and gas tight.

I'm sorry if I'm not respecting the politics of the rocket stove concept.  I'm frankly just trying to make something that keeps a place (an off grid sauna) warm at -60 without burning a forest of trees just to sauna every winter.  I already do that for the main cabin.

I have no idea what clay resourses i have around me (i'm about 50 miles off the road system).  I do have sand and gravel and can haul quickcrete in by the sackfull.

Ok - I'm new to this so I'm probably asking a question that's been answered a thousand times.  I don't get all the monkeying around with bricks and scrap.  Wouldn't it be easier to just weld the whole thing together out of 1/4 inch pipe scraps?  A 6" pipe for the feed tube and combustion chamber and then an 8" pipe for the riser?  If you are welding it you would guarantee it is all gas tight.  Also, instead of a freeform cob thermal battery, could you just build a reinforced wood box and fill it with concrete?