Hello all new guy here looking for advice on first rf smoker build. I'm starting with a 48" x20" air tank 3/16 wall. Just getting started and looking for advice on a few component and steps. I've cut out for the door but had some flex once cut I would imagine this is common but any ideas how to re shape it would be great. Second It seems there is a split between people wanting a square or round fire box I was thinking a square but if air flow will be a issue round wouldn't matter much. and third when you burn the tank pre fabrication how much deflection and warping is to be expected. Any and all advice will be appreciated. thanks