high guys: i am building a gas forge for welding damacsus billets. It is about 9 in high and square and about 18 in long. It has an angle iron frame. I will hold it together with threaded rod. My? is this, will expansion of the bricks be a problem? Maybe i should spring load the rods holding it together. I will appericate and info you can give me. Thianks, Leroyk