Originally Posted by CtTradArcher
I have a New Braunfels Black Diamond offset that I have recently resurrected. I am thinking of modifying the firebox by simply moving it down.
A little about the smoker and my reasoning:
Cooking chamber is 16" diameter by 34" long. Firebox is the same diameter, 17" long, so about half the size of the cooking chamber.
The firebox is bolted on and is located such that the top is half way down the cooking chamber. The opening into the cooking chamber is approximately 10" wide x 6.5" tall.
Smoker runs very hot at the firebox end and according to Feldman's pit calculator, the opening is twice as big as it needs to be.
By moving the firebow down 3.25", I will decrease the opening by about half, which according to Feldman's still just a bit bigger than needed.
It will also move a lot of the radiant heat below the cooking chamber, which I hope lowers the temp at the firebox end of the cooking chamber.
Lastly, it will lower where the heat enters the cooking chamber to below grate level.
The mod should be pretty easy to do and not permanent if it doesn't work. My plan is to just make a plate to bolt to both sides using the existing holes.
Does anyone see any shortcomings with the idea? Or agree with the reasoning?
I cooked for 16 years with Black Diamond and the best thing that I ever did as far as mods was to add a heat deflector over the opening of the firebox in the main chamber. I used an aluminum roasting pan which I cut in half, put the two halves one on top of the other and then attached them to the wall of the main chamber directly over the firebox opening with screws. After the heat interred the main chamber it was directed down and into the center of the pit rather than being allowed to go strait up, move along the lid and exit as it wanted to. The result was better use of the heat from the fire and being able to build a (much smaller) fire to heat the pit. Your pit needs plenty of draft and restricting the opening to the main chamber in any way may lead to airflow problems. Try the heat deflector, I'll bet you'll notice a huge difference in efficiency and getting the pit to hold temps where you want them.