Small smoker stack size help please

[texasslowsmoker]

I have a small offset smoker made from 14" diameter pipe. Fire box is 12" long, smoke chamber is 24" currently the smoke stack is made from 2" diameter pipe x 16" long. I've been having flow issues so I bought a 3" weld 90 and 28" of 3" weld pipe. My question is how long does the stack need to be? Thanks in advance.

 

[bdskelly]

Send a personal message to DaveOmak  I believe I read one of his posts on the subject and think he can help . 

 

[gary s]

24 in. for a 2"  and 12 in for a 3"

Gary

 

[bdskelly]

 
24 in. for a 2"  and 12 in for a 3"

Gary

 

[joe black]

Gary has done a huge amount of research on this subject. I was going to suggest that you contact him. I would definitely use the sizes that he gave you above. As you go through this smoking experience, Gary will be a huge asset.

Good luck, Joe

 

[gary s]

Thanks Joe for the complement 

Gary

 

[dirtworldmike]

Please explain why  only 12" tall?  Would not a higher/taller pipe increase the draft? Wouldn't it be better to have too much draft available with a taller pipe rather than less?, as excessive draft/air flow  can be controlled through the firebox vents if needed?

I'm just asking because I'm complicating increasing the size, length and location of the exhaust on my offset to create more air flow,Thanks

 

[daveomak]

Mike, morning...... Small size smokers, such as you are building need some special consideration.... The tutorial below explains large, regular and smaller smokers and what considerations need to be made, In my opinion.... Along with what I consider, relevant calculations... Dave


http://www.smokingmeatforums.com/t/...others-ready-to-use-rev5-6-19-15#post_1264161

 

[gary s]

OK   you said you’re smoke chamber is 14” dia x 24” length,  which is 3,695 cu. in.

All components are based on CC size, there are formulas that work really well.

I suggest using .02 or 20 %  where Dave uses .022 or 22% 

.02 =  73.9 cu. in which is 23.52 in. for 2” pipe and 10.45 inches for 3” ( I rounded up to 12)

.022 = 81.3 cu. in which is 25.87 in. long for 2” pipe and 11.5 in. for 3”

Now this is a small smoker and I have not tested all the different sizes and lengths for this size. 

Looks is also important,  you don’t want a smoker with a ridiculously long stack as well as one that looks way too short.  So look at your smoker and see what will look good, then size your stack.  I don’t know if a 12” stack would look right or not, you could always go with a 16” and see how it works, if not you could cut it down. But a 12 or 14 may work.   

 

[texasslowsmoker]

Thanks gary. That's why I love this place!