Fire Box Sizing

I'm so confused I'm building a return flow smoker, my tube is egg shaped, measures 21" high inside, and 28" wide inside, and gonna be 8 ft long. I'm still not sure about size of firebox, and size of smoke stack, I tried that pitt calc. still not sure if I did it right, any help with this whould be great.

I come up with 27.5" x 28" firebox and still working on stack size and draft for mine.

This is a great tool to use too.  I have built a few and used this to size it.  Post us a few pictures of the build.  We all love to watch it being built.

http://webpages.charter.net/tomchism/BBQ%20CALC%20Forms/BBQ%20Smoker%20Calculators.htm

Good luck!

Randy

Thanks, when I get it going, I'm sure you will be hearing from me. (help me, help me) lol.  I will try to get pics on here too. thanks for the info.

Quote:

Originally Posted by randy1439 

I'm so confused I'm building a return flow smoker, my tube is egg shaped, measures 21" high inside, and 28" wide inside, and gonna be 8 ft long. I'm still not sure about size of firebox, and size of smoke stack, I tried that pitt calc. still not sure if I did it right, any help with this whould be great.

The pit calc may be hard to get good numbers from on a tank that isnt round or square.

I think I would take the 28" wide number and use it as if the thing was round and not egg shaped. Its going to make the numbers a little high but you can always damper down vs if you make the holes to small you can only open them so much.
 

I ran a tape measure around it, and found a barrel the same measurement around, so I came up with, if it was'nt egg shaped, it would measure 26" inside diameter. But you are right, I can't see where I could go wrong if I just go with a size that I know is bigger than I need. Thanks again don't be afraid to shout out, I'm always open for opinions.

I got a question ? On a return flow smoker, mine is gonna be 6 ft long, I decided to down size it a little. When i put the plate in for the smoke chamber, how much space at other end should I leave open, for the smoke to go up through and return.

I made mine a few more square inchs then the opening from the firebox to the cook area.

Ok thanks, that makes sense, I was'nt sure about that, so figured I better throw that out there.

Randy make sure to post pics of your progress and talk it up, sometimes a mistake will be caught before its made.

I know when I built mine, its success was mostly due to the good folks on several forums.

Oh I will, I sure I'll be needing lots of help from everybody, I did'nt get started yet, I'm only getting started cutting parts, It will be a while before I get started with the build part, but thanks for taking intrest.

Im thinking about putting a smoke stack on both ends of my return flow smoker when I build it, because I think if I don't when I open the door to check on what i'm cooking, I think smoke will be pouring out in my face. So i think if I had another stack on other end, that I can open up when I open door it will cut down on all the smoke. Would this be a good idea or not.

I would only do it as a place to dump heat or increase the draft in the event of low temps and you want to build the fire fast.

The smoke is going to follow the path of least resistance. That said unless you install an evacuater fan its gonna end up right in your face.

One thing that will help is don't mount the rig to low, smoke rises.

I like to be able to hold my arms out straight in front of me and work on the top shelf.

Just like my tables, my smoker is not short people user friendly. It only works for us tall lanky folks.

I'm not pickin on the short peps, sometimes it really sucks being tall. Trust Me.

Yeah, I didn't think of that, mine gonna be mounted pretty high too, thanks.

Being my tank is odd shaped,from the fire box to the smoke chamber I need 129.02 sq inches, the pit cal. does not show me what i need to know. If my tank is 28 inches inches high and it's 21.5 inches wide, if I just go with a 1/3 of the size for the smoke chamber. Which means the plate will lay in about 9.33 of a inch from the bottom, will that give me enough for the smoke chamber, I have know clue how to figure out how many square inches is in something D shaped.

If you make the opening from the firebox to the cook area 20 inchs wide by 9.33 inchs deep and its a sideways D shape you will have an area of  143.93 sq inchs.

If you make an opening 18.5 inchs by 9 inchs tall in the center you will have an area of  129.81.

Just making sure this is what you are talking about. The half circle area is the number you need to be close to 129.02. Correct? And also is this kinda what the end view will be on your smoker or is the egg part laying down?