I recently became curious about Aaron Franklin’s smokestack design while re-reading Franklin’s book, Franklin Barbecue. As an aside, his book definitely belongs in my Pantheon of all-time great books on smoking & grilling which for me includes:
Chris Lilly - Big Bob Gibson’s BBQ Book
Stephen Raichlen - BBQ Bible (and Planet Barbecue)
Adam Lang - Charred and Scruffed
In the book, Franklin fabricates a horizontal offset for backyard use (not for his restaurant). You can see from the attached photos that his design includes a smokestack elbow that extends the entire length of the food chamber (from front to back). I saw where someone referred to similar design as a “collector box” or “manifold” but not sure if that is the correct jargon. (Note that I’m not referring to the vertical placement of the outlet, which is a whole other topic discussed many times here).
What is purpose of this wide exhaust opening? My guess is that it evens out the temperatures from front to back and may also improve draft. In the book, Franklin is big fan of maximizing air flow, which is one reason why he doesn’t use tuning plates (of course he’s typically using much larger smokers in the restaurant environment than the backyard model that is pictured in the book).
I’ve been told by one pit builder that this exhaust design is probably only effective for larger diameter smokers.
What do you think? What is the purpose behind this design? Would it have noticeable impact on horizontal offset with 24” diameter? (Assume length anywhere from 36” to 48”).
Chris Lilly - Big Bob Gibson’s BBQ Book
Stephen Raichlen - BBQ Bible (and Planet Barbecue)
Adam Lang - Charred and Scruffed
In the book, Franklin fabricates a horizontal offset for backyard use (not for his restaurant). You can see from the attached photos that his design includes a smokestack elbow that extends the entire length of the food chamber (from front to back). I saw where someone referred to similar design as a “collector box” or “manifold” but not sure if that is the correct jargon. (Note that I’m not referring to the vertical placement of the outlet, which is a whole other topic discussed many times here).
What is purpose of this wide exhaust opening? My guess is that it evens out the temperatures from front to back and may also improve draft. In the book, Franklin is big fan of maximizing air flow, which is one reason why he doesn’t use tuning plates (of course he’s typically using much larger smokers in the restaurant environment than the backyard model that is pictured in the book).
I’ve been told by one pit builder that this exhaust design is probably only effective for larger diameter smokers.
What do you think? What is the purpose behind this design? Would it have noticeable impact on horizontal offset with 24” diameter? (Assume length anywhere from 36” to 48”).
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