British BBQ Society Forums

I'm just in the middle of building a UDS, however I've just realised I haven't done anything for a chimney, how have you all done your chimneys & is there anything you would do differently?

I'm planning to use the lid from my oil drum (I got one with a clamp on lid) Mainly need to know what diameter I should be thinking for the holes as I know I cant have them too big or air would get in through them!
As inlets I've got two 3/4" ball valves, but they aren't full bore, I'm hoping they will provide enough air, if not I can always add two more!

I haven't taken any pictures as yet, however am happy to do so if anyone is interested, also all my parts were sourced from eBay so if people want i can also send links!

Like you i am currently mid build of a uds.
For the chimney i have fitted a 4" long 2" pipe nipple in the large bung hole.

I have not gone for ball valves as they, along with the pipe work seem to be a bit over kill and pricey to me just for air flow.
Instead i have gone for 3 x 1" holes plugged with stainless steel perforated air vents which can be closed or opened by pet tags, a bit like a covered keyhole, all for less than £10 ..much better (if it works)
I have two more that can be fitted if need be, not tested yet as i'm waiting on my ash pan to arrive.

When I used my UDS out in the open I didn't bother with a chimney because the smoke dispersed easily straight from the bung hole but since I built my shelter I just have a piece of 3" dia steel tubing that I found in a skip that goes over the bung hole so that the smoke disperses above my head height. It isn't welded on just free standing so easily removed when I need to take the lid off

I don't have a bung hole in mine as I got a removable lid drum!
I'd like to put a short chimney on it mainly to take the smoke up and away and also possibly help with the draw through the air intakes. I'll have to have a look see what i can find, My biggest drill bit is 32mm so i need something that goes into a 32.5mm hole that way i can use a threaded fitting and not need to worry about nuts & washers!
I picked up my ball valves from china, got two female 3/4" ball valves and a matching threaded male-male connector for £14. Took a little while to get to me but worth it for the savings over buying ball valves in the UK.
The threads gripped into the drum nicely when I drilled a 24mm hole (0.5mm narrower than would be needed to allow it to move freely) which I think will have given me an air tight seal!

All in so far I've spent £85 including drill bits. And thats everything ordered via eBay, with the exception of my actual grilling rack, that was a homebase find @ £5!

Yeah built 2 UDS's just recently one for hot and one for cold smoking.
On the first I put 3 x 3/4 brass hex nipples with caps plus a 3/4 ball valve for the intakes at the bottom and drilled the lid to take 8 x 3/4 nipples with caps for the exhaust.
The second was the same on the bottom but the top was 6 x 1 inch brass hex nipples. The only reason for the change was just supply of parts. The nipples etc. came from Screwfix at £1 each.

Both work great

You will want a ball valve with a female end if you want to run a Guru on it

My barrel came with removable lid that had both bungholes in..which i thought was odd but hey ho
Have a look on youtube for a guy called daddy cooks, you could do something like that.
4 x 1" holes 3/4 inch nipple with elbow bend.
I was gonna do that but seeing as i got a free bung hole i stuck with that.

Is brass safe to use with a barbecue? I thought that brass was in the same category as galvanised when it came to barbecues.
I've found these... http://www.screwfix.com/p/brass-hexagon-nipple/92631 but I cant find the caps/domes you mentioned?

Just ordered these http://uk.rs-online.com/web/p/malleable ... s/2434196/ will let you know how i get on!

Galvanised products are a totally different ball game and have had many discussions on all forums.

However brass is treated the same as Copper for cook wear but in this instance they are only used for air intake and exhaust they don't come in contact with food. And once seasoned they are coated; together with the fact that most UDS are used for Low and Slow so the temps achieved are not worth worrying about.

I have 316 SS for mine but wouldn't bother again , they dont even get hot and I can hold them (outside at least) with my bare hand.
I have looked at the same nipples and thought about using them if I build another unit.