I'm on my second trailer smoker and figured out all the stuff i didnt want when i made my first, i didnt do a reverse flow on the first and that was a mistake (i was trying to stay cheap and easy) but cause of the temp difference side to side, and the amount of charcoal/wood I go through im def doing reverse flow on this one. and ive ran into space issues so im upping the size from a 320 gal to a 500 gal with two level sliding racks instead of one stationary which will more than double my cooking space. Here is the Question has anyone ever tried using stone as the baffle? I wanted to use road plate 1in steel to have as much thermal mass as possible to maintain temp, but alas my last name is not Gates or Trump so I need something cheaper. I could to a thin steel or i have easy access to free marble and granite (we share a building with a counter top company and there are always 2-3ft scraps i could tile together and I think i could get a good seal by using angle iron as a bracket for them to sit in and stove rope at the contact point, what are everyone's thoughts am i crazy? or should i use thin steel to make sure i get a good seal and then just put the stone on top of that. along with that would stone in the bottom of my non reverse flow help maintain temp, Ive heard of a lot of people using sand? it is an offset 320 gallon, would filling the bottom with a few inches of sand help?