side pipes on a uds

[smokinjoes]

@bill1  Awesome,  thanks much for your take on my ramblings you seem to have hit the nail on the head with what i was chewing no there, that all sounds very logical :)  I do agree to err on the large side sounds like the best idea.  Especially when you have flow control on each side.  :)

Merry Christmas!

Joe

 

[rabbithutch]

I recall having read somewhere (although I can't find it now) that adding bottom intakes that can be capped off was to allow enough rapid air flow at the bottom to get a bed of coals or briquettes going good then be able to cap off the bottom feed and fine tune with the one - usually elevated with a pipe and ball valve.

I have not (yet) built a drum smoker (I hate to call them ugly because I think there is beauty when form and function meet so well.). So I'm not speaking from knowledge built on experience, just adding 2¢.

 

[smokinjoes]

I totally get what you are saying about the faster air flow for getting it going or raising temps, but this doesn't work unless you have the top wide open to match the bottom.  I was more getting into the ideas of controlling the exhaust flow to hold smoke or clear it faster for a heavy/light smoke flavor :)

I agree with the fact that the term used for these is unfortunate, UDS.  I've some pics of rigs (including this one  congratz!) that are far from ugly.  Then there is fact that this is a recycled product so it is stopping these drums from hitting a landfill or best case scenario a metal recyclers.  No materials were pulled out of the ground, no manufacturing process, just green and functional :)

 

[tristhullsmoker]

I have recently ordered a brand new clean drum from amazon, along with digi thermometer and analogue with a view to build my first uds probably next weekend, however the air intakes I am struggling with for purely aesthetic reason and its my vision I am going for 2 upright with valve taps and one low with a simple end cap. I can find galv pipe now I know its a no no for cooking with but as an air intake is it ok? Also what diameter fittings are best? I am going for no welds too, I am tearing to bits my first smoker for the internal, it was a decent one to start with but it shall be sacrificed. Cheers guys

 

[bill1]

I wouldn't worry about zinc (galvanization) on inlet air pipes unless you're doing something tricky like extending them into the center of your coal/fire source.  As long as they end at the drum wall, they're being cooled on the inside and outside by room temp air.  I assume you're going to do a "seasoning" run so you can inspect them afterwards and see if there's any whitening of the surface (oxidation of the Zn) at the input to the drum.  If so, you might want to change out the final nipple to black iron or brass or SST.  

You're usually best off sizing your fittings (meaning your valves?) to be the same size as your piping.  (Was that your question?)  If you're using two (and a 3rd stubby for fire starting before a proper draft starts) I think you'd be OK with 3/4 pipe, but I suspect most UDS builders would tell you 1".  Since this is a bit dependent on the fuel you use and how you stack and space it, and since you say you already have a smoker (UDS??), you probably have an experimental base to guide you on the piping size decision?