Hi all, am planing on building a rocket stove heater (without the mass) I intend to build the fire box and riser out of fire bricks. A couple of questions have arisen . (1) Do I have to insulate the outside of the burn chamber and the riser?Would be nice if I didn't have to.(2) is there a minimum clearance measurement for the gap between the outside of the heat riser and the inside of the outer barrel.Cheers Pete
