My first 500 Gal RF Smoker - Jimmy Sean

[Jimmy Sean]

First thanks everyone of you who share your knowledge. I bought this tank a year ago and now planning on how I'd like to build it out. I ran all the numbers through the calculator. If anyone would be gracious enough to double check my numbers it would be greatly appreciated. Also if I'm in left field kicking dirt on some aspect of this please call me out.

The barrel of the tank measures 81" and 30" in dia not including the end bells. I calculated the CC volume to be 79,375 in3. That is with the square top. FB size is W-34" X H-24" X L-33" and the volume is 26,598 in3. Chimney size is 8" pipe at 26.5" in length. Throat size is 213 in2 and will be half moon shaped. Intake is 80 in2 and i'm thinking (2) 10" x 4" openings.

Here is the tank.


And here is what I'm thinking conceptually.


Thanks,
Sean

[Pete Mazz]

I'm getting ~90,000 cu in CC using my Square Door Tank Volume Calculator and guessing some of your numbers. You've got a 300 gal tank which is ~70,000 cu in by itself. See my sig for the calc.

[Rodcrafter]

Just using the pit calc without the end bells and the square feature this is what I got.

Cook Chamber Volume- 57,255 cu I'm guessing Pete is right on the size. The end bells do count when figuring size.
Actual Firebox Size-26,928 cu
Rec. Firebox Size-19,085 cu
Firebox Size % Diff-141.09 % This may be close to the right size when we get the real numbers
Rec. Chimney Vol.-1,346.40 cu
Chimney Length-26.8"
FB Intake Area-80.78 sq
Count of Intakes-.50 You don't have to have this big of intakes, but as long as you can adjust them down as the fire builds it is fine.
Rec. Throat Size-215.42 sq

http://www.smokerbuilder.com/pitcalc/

That is my 2 cents worth.

I would think about one thing though. If you are going to ever be filling the whole thing with meat and such you may want to build a warmer box over the FB while you're at this point. I say that because you can get rid of the one end bell for sure, and move the stack(now). Then if you choose to take the other end bell off it would be hard to tell it was ever a tank at all.

[Jimmy Sean]

I'm getting ~90,000 cu in CC using my Square Door Tank Volume Calculator and guessing some of your numbers. You've got a 300 gal tank which is ~70,000 cu in by itself. See my sig for the calc.

Thanks Pete. I re-ran the numbers with having the right side flat and I get ~84300 cu in CC using your square door calculator. The square section I have at 20" tall.

That is my 2 cents worth.

I would think about one thing though. If you are going to ever be filling the whole thing with meat and such you may want to build a warmer box over the FB while you're at this point. I say that because you can get rid of the one end bell for sure, and move the stack(now). Then if you choose to take the other end bell off it would be hard to tell it was ever a tank at all.

Rodcraft that had crossed my mind last night about cutting the one bell off completely. I think it only makes sense to do that as it seems goofy just to leave that portion of it. i can make a fire pit out of the bell. I'm really leaning on insulation the FB too.

By adding a warmer box does the volume of the FB need to be increased?
Is there a minimum height for the FB? I ask because I'd like to make it as short as possible. I'm not that tall 5'-5" and with a foot of clearance under the FB once on a trailer I'm concerned the smoker will end up being pretty tall.
Regarding the stack is it better to come out the end of the square section or the top? If the end then the warmer would be about 2ft deep.

[motoridr09]

The warmer box does not go into the calculation for the firebox size. I don't think this smoker will be that tall and I think going with square doors will help with height concerns since you will be opening them towards you instead of lifting up and down. For the minimum height of the firebox, you want the top of the firebox even with the top of the opening to the cook chamber. I see your height you have calculated for the firebox is 24 inches. I probably wouldn't go much shorter than that. But that's just my opinion.

[Pete Mazz]

Your FB at 24" H will be ~36" square to get you to ~105%.

[Rodcrafter]

Man I hate it when that happens. I typed all sorts of stuff to try to help out and darn it I lost it.
You don't need to have a foot of clearance under the FB because the axle will be way back there.
But anyway take a look at some of these cookers. These guys are a part of the crew here.

http://www.shirleyfabrication.com/

[Jimmy Sean]

I must be some kind of special. I went out to move the tank and prepare to cut it open. Lifted the lid and took a peek at the tag.


For whatever reason I thought it was a 250 gallon tank and then Pete corrected me and said it was a 300 gallon. Nope it's a 500! My memory failed me.

[Rodcrafter]

Hey just so you know Frank has plans for that size tank. I believe it's called the "Big Poppa "


Making memories.

[Frank_Cox]

You might consider going with a square cook chamber instead of using that tank looking at the pics in the first post. You will have the same amount of welding to do. Check out my thread in reverse flow smokers called Mack.

[Pete Mazz]

That's a beast! You could cook for an army with that!