Welcome aboard! The design that you mentioned isn't really ideal because the FB needs to be mounted low on the cook chamber for everything to work right. You could put a false double wall in the middle and add a FB on one end for a RF and build a charcoal grill on the other end. You can plug you dimensions into the pit calculator and it'll figure your FB size and other dimensions.
So, I am picturing a normal reverse flo smoker using half the pipe and then a charcoal grill using the other half of the same pipe. Right?
No reason why it won’t work but a few things to consider. First, a hot charcoal grill (in use) on one side is totally going to play games with your temp co troll on the smoker. It would be like having 2 heat sources for a smoker and I would think challenging to control. Second is size/weight. Assuming it will be mobile, I see a lot of extra weight to move around then only 1 side is needed.
A sketch would definitely help us to see what you have in mind. I remember a build that was similar to this a few years ago that a member built and I believe that he put a double wall between the smoker CC and the grill so that he didn't have the radiant heat from the grill causing temperature issues in the smoker side. I know that TQ builds a 36'' grill directly on the end of some of his builds and the guys that use them love them so it will work if done correctly.
Options come to mind: cut completely In half and make two separate units.
Double wall the divider with insulation so the effect of two heat sources is not as extreme.
Just go big and make it one large reverse flow unit.
With a job this large I'd think pretty serious about what you will actually use it for. Do you need a separate side.
If I am hearing you right you want to cut that tank in half and make a smoker and a griller with it? Cutting it in half you would have very low cooking chamber.
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