Hello, I have been lurking about for a while now – reading up and learning. I soon will be tackling my own reverse flow smoker build, and wanted to run a few things by the group.
I have acquired a used 37.5” diameter by 10’ long propane tank that is in pretty good shape and I am considering how best to make it into a proper reverse flow meat smoker. I am thinking of converting it so that roughly 6’ to 8’ of the tank is configured in the horizontal position and then adding ¼” steel to form a vertical box smoker at the end – so in an “L” shape when viewed from the side. As might be expected, the fire box will be under the vertical cooking chamber feeding the underside of a ¼” thick steel baffle plate that directs the smoke to the far end of the horizontal cooking chamber.
Hopefully my intent can be seen in the attached illustration. The blue cigar shape represents the tank as the horizontal cooking chamber. The green square box in the upper left is the vertical cooking chamber. The red box to the lower left is the fire box and the extension of the baffle plate (in red) into the horizontal cooking chamber.
Question: I am wondering about the wisdom of the horizontal AND vertical cooking chambers setup with only one firebox feeding both?
I have seen some smokers very like this design, and I have seen others where the vertical chamber is setup not for smoking but to create a warming box. My thought is to have two pairs of chimney pipes – the first pair (colored red) for exhausting the horizontal cooking chamber as can be seen with the thick yellow line representing the flow of smoke. And a second pair (colored orange) for exhausting the vertical cooking chamber as can be seen with the thick dashed yellow line representing the flow of smoke.
I figure I would have a small adjustable opening between the firebox and the vertical cooking chamber so I could close off and isolate the vertical chamber to prevent the entry of smoke and additional heat – so it would be used for keeping food warm. However, if I desired to use the vertical chamber for cooking and not warming, I could open the door between the firebox and the vertical cooking chamber. And if I only wanted to use the smaller vertical cooking chamber, I could have a door to close off the larger horizontal cooking chamber and be able to have a much smaller fire in the firebox. Hopefully that makes sense.
Another Question: Does having one of the cooking chambers right on top of the firebox create a significant amount of heat? In the illustration I added what is supposed to be fire brick at the bottom of the vertical cooking chamber. Is this overkill or a wise idea?
And yet, another Question: Regarding the stacks/chimneys: I have seen some builders state having the intakes (for exhausting the smoke) at the bottom or just under the level or plane of where your meat is placed. This implies that your meat is sitting in a constant cloud of smoke and heat. However, I have seen other builder’s state that the stack/chimney intakes should be at the top of the cooking chambers there by having much better air flow and less stale smoke. Can someone please speak to the pros and cons of each design?
Anyway, I welcome any thoughts and ideas you all may provide. Particularly important notes and things I should make sure I am aware of and account for. I am wise to Feldon’s excellent calculator and have been plugging away at it. I just want to make sure I have a sound idea and understanding of what a proper smoker design should be.