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Another new guy with fire box questions

Discussion in 'Side Fire Box' started by xprmntl1, Nov 1, 2010.

  1. xprmntl1

    xprmntl1 Newbie

    Ok, here's what i've got, a 250 gallon propane tank that someone already cut into. I'm needing to figure my firebox size but am having trouble with the calculators on here. My smoker main body is 30in diameter x 66in. long. I was planning on building my firebox 30w x 24h x 24 long. Also how big does my box to smoker opening need to be and how long should my exhaust be? Thanks![​IMG]
  2. mballi3011

    mballi3011 Epic Pitmaster OTBS Member SMF Premier Member


    Well thats all sounds good to me but I bought my smoker. Can you stop into Roll Call and introduce yourself and your equipment. But then you can wait and someone will come around and give you all the info that you'll need.
  3. adiochiro3

    adiochiro3 Master of the Pit OTBS Member

    Looks like a big project!!  Can't wait to see pix of the progress.  I've never built a SFB unit, but stick around and someone will be along to help with the calcs.  Welcome to SMF!
  4. xprmntl1

    xprmntl1 Newbie

    Well, went ahead and got started on the firebox yesterday at weld class, dimensions are 30w x 24 1/8 x 24 1/8. Guys at class are questioning its size, but I told them I researched the net and what I came up with is firebox should be 1/3 the size of the smoker. This thing is heavy and huge, it took 3 guys just to get it on the trailer and i'm not done with it yet! Made out of 3/8 AR plate.[​IMG]
    Last edited: Nov 2, 2010
  5. jonnyrod

    jonnyrod Fire Starter

    Your firebox is plenty big, better than too small. According to the calculator you need;

    17" x 8" rectangle firebox to main cook chamber opening

    4, 4" rectangle firebox air inlets

    A 69" stack at 4" i.d.

    These #s change if you go from rectangular to circular as well as stack length depending on what size pipe you use.

    You can also use square tubing as long as you have 864 cu inches of volume.[​IMG]
  6. sqwib

    sqwib Smoking Guru OTBS Member

    Off to a good start.

    Looking forward to the build photos

    In my signature is a pit calculator
  7. xprmntl1

    xprmntl1 Newbie


    Actually I am almost finished now, just need to cut the hole for my temp. gauge and finish the other side of the trailer for my wood storage. Been pretty busy working on it on my days off. Thing cooks great, holds a good even temp even in cold temperatures!
  8. Look's Cool!
  9. Hey hey that rig of  yours there looks mighty NiCE. I like the way you positioned your firebox in there into the cooking chamber. Inside pics please, inquiring minds want to know! [​IMG]  
  10. Sweet setup! Just one request: More Pics [​IMG]
  11. realtorterry

    realtorterry Master of the Pit OTBS Member SMF Premier Member

    very nice. great job!
  12. Nice. Very pro looking. Need more detailed pics though. Inquiring minds and all that.
  13. xprmntl1

    xprmntl1 Newbie




    Here's the firebox to smoker damper, I made several settings to shut down heat if needed. I need to make changes to my fire grate, my cast iron ones have got too hot and bent.
    Last edited: Dec 24, 2010
  14. turn4fun

    turn4fun Fire Starter

    For your firebox grate, how about using some of the same size angle iron you used for the riser.  Cut several pieces that will set down in your framework like this:


    Lay them in with enough of a gap between each one for adequate airflow and for ash to fall through, and just tack them in place.  Should never warp enough to matter.
  15. SmokinAl

    SmokinAl SMF Hall of Fame Pitmaster Staff Member Moderator OTBS Member ★ Lifetime Premier ★

    That's sweet xp! Great job, can't wait for some Qview!
  16. Looks really good.  Whats a final price on the build?
  17. michael ark

    michael ark Master of the Pit