UDS air intake question...

darthtrader

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Hi guys-

I've been getting all my parts together to build myself a drum smoker and I wanted some expert opinions from you all about the air intake. I'm undecided on whether to give my UDS four small intake holes with some valves or just one big hole with an adjustable cover to regulate temperature.

My question is this: is having four smaller holes pivotal to creating the convection effect and would I lose that effect if I only had one big air intake hole?

Thanks in advance.
 
I dont know that there would be a difference. I have three 1 in nipples on mine and usually only have one open.
 
If you go with valve set up. Go at least 3/4" and put caps on all except 1. I run on valve and if need more temp I remove 1 cap and throttle valve back and so forth. This is how I roll. Keeps cost down.
 
If you go with valve set up. Go at least 3/4" and put caps on all except 1. I run on valve and if need more temp I remove 1 cap and throttle valve back and so forth. This is how I roll. Keeps cost down.

That's what I am going to do on the next one. Mine have 4 - 1/2 valves and really your suggestion would work just fine and be less expensive. I also used 4" pipe nipples but I think the shorter ones might work better. One we built with 1 inch nipples and the air flow seems to be more consistant to the fire. The cool thing about these wonderful smokers is that it all works once you cook a time or two.
 
I'm still in the construction / learning phase on this thing, but I had a local muffler shop bend a 2" inside diameter pipe for the intake. The exhaust stack is 2 3/4"inside diameter. With a load of R.O. lump, running wide open, I hit & held temps of over 400*. The intake comes into the drum about 2" above the bottom of the drum.
Outside air temps were in the mid 60's, light breeze.
No adjustments on the pipes yet, those will come this week.
 
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I used four 1/2" pipe nipples for intakes, one with a valve and the rest have caps. They are 6" long, and they hold my ash pan off the drum floor, and it also keeps the intakes clear of debris.
 
I used four 1/2" pipe nipples for intakes, one with a valve and the rest have caps. They are 6" long, and they hold my ash pan off the drum floor, and it also keeps the intakes clear of debris.
What are you using for an ash pan? How far off the ash pan does your charcoal basket set? Pics please.
 
I definitely got to take a few pics. The ash pan came out of my GOSM and the charcoal basket stands above it. When I swipe the camera from work again I'll post some pics.
 
When putting the air intake in how do you seal up any little holes around the pipe . same goes for the ball valve ?
 
When putting the air intake in how do you seal up any little holes around the pipe . same goes for the ball valve ?
Not sure what you mean by seal up holes. If you use a 1" hole saw or something to make a 1" round hole a 3/4" pipe nipple screws in. I weld mine in but you can use conduit nuts, one on inside and one on outside to lock it in.
 
I put 3/4" ball valves in mine that had threads on them. I used the conduit nuts to lock it in, and by being careful with my step bit, I rounded out the hole so the valves threaded in to make a tight seal. You could always use some high heat gasket maker around if you have a hole to big.
 
If your hole is too big go to hardware store and get 1" washers and sandwich drum between valve and conduit nuts. Have done this when installing temp gauges.
 
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