Quick air flow Querry

[bigfork]

Hi there,

Relatively new to the forum so I want to preemptively thank this community for its limitless supply of knowledge...wow!  So many questions have been answered just by perusing. 

I've got a couple of quick ones.  First, my smoker (I know...I've got to post pics):

--salvage barrel, 15.5 in wide by 21 in tall (aprox 3,960 cubic inches according "Feldon's BBQ" calculator). 

--stack is 2.5 in wide and 6 in tall, adjustable

--air in is via 2  inline ball valves opening vertically after an 90 degree elbow.  They  are 3/4 of an in wide located near the bottom on opposite sides.

I've got the funny feeling I'm not getting enough air "in".  More air?  Am I choking it?  I've noticed that I can't shut the two valves at all or I quickly kill the heat as if it's already running at a choked down rate.

Also, what is the purpose of the intake stacks that rise up the outsides of the barrel to near the top.  It seems it's popular to have two low  and then two returning to the height of the lid. Are these just  style points or is there some sort of convection logic going on?

PS All I've ever done is jerky with the thing.  I start in the oven for most of it and then give em a blast in the smoker for a finisher.   I get good results but I'd love to do it all in just the smoker.  I've definitely got more to figure out...ha

Thanks folks!

 

[daveomak]

BF, morning and welcome to the forum........  The vertical risers for the air intakes, are for convenience in adjustment.... Unfortunately they severely restrict the air flow.... choking it off...  The 90 deg elbow at the bottom to facilitate the install of the riser also restricts the air flow.....  A valve straight into the drum using a pipe nipple works best...    One solution is to attach a handle on the valve lever to adjust the air flow...   something along this line will work.....   Dave

 

[peddler]

Be interested to know how much restriction and if one could step up the pipe size and regain that which is lost. In realty the ball valve even restricts some.

 

[bigfork]

I'm going to tap another 3/4 pipe nipple in the back...no 90 return or ball valve...just a threaded cap.  I think this is going to fix my air-in problem.

We'll see!

thank for the tips,

bigfork