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100 Gallon reverse flow smoker build

Discussion in 'Reverse Flow' started by mohunter09, Dec 2, 2013.

  1. mohunter09

    mohunter09 Newbie

    Im  looking to build a reverse flow smoker out of the 100 gallon tank I purchased last year. I planned to do a build very similar to DPP but have since changed my mind! I need to know how to set up my 100 gallon tank to be a reverse flow smoker! Have everything to build it just need to know how big firebox needs to be where stack or stacks need to be and how to really make it "reverse flow" vs traditional offset..
  2. mohunter09

    mohunter09 Newbie

    Ok from what I understand you want firebox to be about 1/3rd the size of your pit...I was thinking needs to be about 24 inches square? Then the reverse flow plate travels from firebox end of smoker to beginning of opposite curved end of tank and it travels back to either single or double stacks closest to firebox?....looks simple enough but how much do you cut out of the tank how big should hole be?
  3. daveomak

    daveomak Epic Pitmaster OTBS Member SMF Premier Member

    Mo, morning.... The FB should be as wide as the RF plate or wider.... Easy fit up that way.... Dave
  4. mohunter09

    mohunter09 Newbie

    I was told 20 inches square
  5. daveomak

    daveomak Epic Pitmaster OTBS Member SMF Premier Member

    Did I tell you that ?????

    24" sq FB is 60 gallons...

    20 sq in = 34 gal

    20x24x16=33 gal
  6. mohunter09

    mohunter09 Newbie

    No a smoker builder over at the smoke ring
    Told me a 20 inch square box would be more than adequate with a 32 inch 4 inch diameter smoke stack and a 6.5 and 13 wide opening
    On tank to firebox
  7. daveomak

    daveomak Epic Pitmaster OTBS Member SMF Premier Member

    Well, 20 square is the correct size in cubes or gallons or whatever measurement you want to use... 20" may not be the right size depending what size your CC is.....

    You asked a question.... I answered it with one dimension that would make the build easier... not knowing anything else about the smoker.... The width of the RF place us where smoker builds should start.....

    I'll let the guys/gals at the smoke-ring help you with your build....Since you started your build questions over there, they should be the group to help you finish your build..... have a great day.....
    Last edited: Dec 3, 2013
  8. mohunter09

    mohunter09 Newbie

    Thats probably the saddest statement ive ever read on a forum...I ask  two different places hoping to get lots of ideas and help...didnt know who would respond or if I would get responded to at all...the fact that you were rude because I asked help on another forum is disgusting..its a forum not the end of the world.
  9. abaralnek

    abaralnek Fire Starter

    Really Dave? Your not the only pit builder and proby far from the best. Mo was told a 20" box would be good, maybe you didn't tell him that, but must you come off like your opinion on pit building is the only one that will work? "Did I tell you that" wtf is that Dave?
  10. jarjarchef

    jarjarchef Master of the Pit OTBS Member

    Not an expert here and did not stay at a Holiday In Express either.....

    It is very difficult to tell you precisely what to do. Only suggestions can be given. If you look at most of the RF builds you will see they all vary a bit and are custom to the builders or customers taste.

    A simple description of a RF smoker is you have a horizontal cook chamber with a fire box to one side. The smoke and heat pass under a metal plate that runs about 85% the length of the cook chamber. The smoke and heat rise into the chamber and then travel to the opposite end where there is a stack at the fire box end where the smoke and heat exit the chamber. The air flow is the key to this style of smoker to work properly.

    Not sure if allowed, but here is a link that should help with some of your design: http://www.feldoncentral.com/bbqcalculator.html

    You will be able to play with the numbers on your design to get an accurate dimensions for the stack, fire box, openings, etc.......

    As stated earlier it is usually easier on the build if your fire box is the same width as your RF plate. This way they match up better for the weld seems. To determine the width of your RF plate and fire box will be determined by the width of your tank at the point where they will sit. The calculator will help with that. I have seen the placement of the RF plate as close as 4" to 6" under your bottom rack.

    For how far to inset your fire box. That really is up to you and what you want. Most if it is a dome end they will inset to the weld seem. Most if it a flat cut off end will not in set it.

    Stack placement is at the firebox end. The length is determined by the diameter of the tube, you are not limited to round square will work, just need the correct volume for the draft. Wider is better for less resistance of the air flow.

    If you are able too, go a little bigger on your fire box, vent opening and stack size. This will give you more wiggle room for the numbers.

  11. daveomak

    daveomak Epic Pitmaster OTBS Member SMF Premier Member

    Mo and abar, morning..... You are correct ...... I was an a-hole in my response.... I apologize......

    Lets start over.....

    I need to know the dimensions of the tank you are using for a CC..... The gallon capacity is not enough information to come up with the proper dimensions for the FB...... The diameter is needed to determine the width of the RF plate, and the length is needed to determine the length of the RF plate.....
    Once the RF plate dimensions are calculated, the minimum dimensions of the FB can be figured.....

    If you would like me to figure out some numbers, I will be happy to do so.....

    Again, I apologize for my stupid, asinine, rude attitude....... Sincerely, Dave
  12. Go just a tad wider than your tank, try for 24" tall and about 20" deep, then check pit calculator. You want some height to your firebox!
  13. mohunter09

    mohunter09 Newbie

    I'll try to get dimensions ASAP thanks for the more welcome help
  14. alaska

    alaska Meat Mopper

    Oh Boy...My turn! I am glad you waded through al that stuff and now I can say WELCOME and glad your here. I have never built a RF and the guys on this forum answered all kinds of question for me. Many have opinions and  different design but all of them want your experience/build to turn out great. I look forward to tracking your build and please post photos. Jerome
  15. mohunter09

    mohunter09 Newbie

    24 diameter and 50 some odd inches long was measuring in dark called local metal fab and
    Smoker builder to price building me a firebox of quarter inch steel
  16. daveomak

    daveomak Epic Pitmaster OTBS Member SMF Premier Member

    There are many variations when it comes to building a SFB/RF smoker..... these numbers should get you a smoker that works very well... easy on fuel.... easy to control temps... easy to fit up... Firewood grate place about 4-5" from the bottom of the FB... Food racks start about 4-6" above the RF plate.... Door hinge pins should be behind the door seal for easy access....
    OK..... We need pictures to quench our appetites..... Good luck on the build......


    CC...24x55=24,880 cu. in.
    FB... 8200 cu in...... 22" x 22" x 22" .... about 30% oversized.... 10,650 cu. in.
    Stack... 423 cu in ....... 4" ID stack 34" tall above the CC
    FB Air inlet...21 sq in. + 4 sq in upper air inlet
    FB / CC opening... 100 sq in .....
    Area under RF plate... 100 sq in
    RF Plate Width..... 21 1/4"(AB) x 6" short of the end of the CC..

    A semi circle, the diameter of the CC (r), cut in the top of one side of the FB with the depth of 6.5"(ED) will give you the 100 or so sq in opening...

    .............Click on any image to enlarge..........

    ........A simple heat shield design.....

    Last edited: Dec 6, 2013
  17. mohunter09

    mohunter09 Newbie

    That's pretty much exactly what I'm going for just not quite understanding heat shield and the dimensions to RF plate have me confused ? Everything else is exactly what I've gathered I need to do I actually am having local guy price me building just the firebox since it's going
    To be hardest for me since all I have is torch and I'm not very good with it
  18. daveomak

    daveomak Epic Pitmaster OTBS Member SMF Premier Member

    The RF plate will match up with the top of the FB once both are installed to the CC.... Cut out the CC so the FB slides in about 7-9".... and matches up perfectly with where the RF plate sits if you set it in the CC.... The RF plate length will depend on how far you slide the FB into the CC.... When you cut the partial circle out of the FB, you can leave a horizontal section at the bottom of the circle for a "grease dam" or what ever they call it... about 1" high...

    The heat shield is in the event, the RF plate gets too hot and you need to deflect that heat.... It can be installed so it covers the top plate of the FB also for some insulation qualities....
    Last edited: Dec 5, 2013
  19. mohunter09

    mohunter09 Newbie

    Interesting well I'm continuing the smoker build but what's everyone's thoughts on a WSM are they worth the money ? Never cooked on store bought smoker
  20. WSM is a different animal altogether. I'd focus on a true pit to get the best experience.

      Nothing against Weber, its a fine company with quality products. Another American Icon!