So I have a fairly cheap-o Brinkmann vertical offset. I've done some mods putting gaskets on the doors, but the firebox is REALLY leaky on the air inlet side. It's similar to
this, with a fairly large "D"-shaped door below the intake damper on the firebox (for ash removal). I've put a high-temp gasket around this door, but the metal just isn't thick enough for me to get it flat and tight to the box without warping and opening some gaps. So it tends to run kind of hot, despite my efforts at using a minion approach - the fire just spreads really fast.
I'm kicking around the idea of trying to get a new firebox made to replace this thin-walled POS. Anyone with any experience with this? I really like the rest of the smoker and it'll hold a TON of meat, but it's really hard to keep a low, steady fire for a long cook.
I'm also looking at bending some metal to create more of a "snake" burn in the charcoal but I still think I'm getting too much air in there.
Edit - assume for the moment that shooting the lock off my wallet for a $1K smoker isn't in the cards.