chad Christopher wrote:Insulation around the base of your stove design is good! You want to insulate the burn tunnel. But you do not want to build mass around it, which is what i think you mean. You wanted mass for long term heat storage, by the sound of your post. You may want to INSULATE, the burn tunnel for a better faster hotter flame, and alter your exhaust, and gather heat in mass around the exhaust. Iooking at your design, i would personally make some sort of granite gravel gabion type tube aroumd the exhaust flue. Such as duct pipe that can snap close around the existing pipe, then fill with some kinda pea gravel.? Maybe tack weld another propane tank on top of the existing, filled with sand and gravel. It wouldn't bridge much heat directly from the stove, but still collect rising heat, not robbing the system of the heat it needs to function properly.