Building my own

Hi, just joined your excellent forum after looking for inspiration on the 'net, and finding it! I have laboured under the delusion for years, as most in England and apparrently Australia do, that our habit of turning perfectly good meat into cinders come summer is actually barbecueing. I wish to redress this by building a smoker and learning the secrets.:-D
I've 'obtained' two old propane cylinders, one about 5ft long the other about 2.5 ft, both 20" diameter, to use as the cooking chamber and firebox. I am also lucky enough to work somewhere where they threw out (yes threw out, idiots!) 10 perfectly good 900x600x3mm sheets of 304L stainless steel, as well as several lengths of thick-walled 1" square tube. Now, I only intend this to be for backyard use so it won't be built onto a trailer but it'll hopefully fit into my utility trailer which I use to lug all sorts of stuff about.
Anyway, I've already picked up some invaluable information about baffles and tuning plates. My thinking is to mount the firebox cylinder vertically and make it in such a way as it has a removable lid so I can use it as a chargriller if I want to (this may be subject to change). This will allow me to install a big enough stainless steel firebasket to provide sufficient heat for the cooker. Knowing what I've only recently learned I'll be adding a baffle and tuning plates, as well as a well-sealing air inlet on the firebox and an exhaust damper in the stack. The doors will have rope seals and temperature gauges.
I've looked at a schematic of the various layouts of smokers and wanted to ask opinions on standard flow (one end to t'other) versus reverse flow, since I'm in a position to make it either at this stage. Is one inherently better than the other or are they about the same?
Since I've got all this stainless kicking about I was thinking of adding an extra vertical smoke chamber in the exhaust path as I've seen some commercially-produced designs have, are these there for lower temperature smoking or just to maximise heat use and smoking capacity?
Sorry this i sa lot of questions but I want to try and get it right first time if I can:redface: :grin:

Thanks for the replies gents, I was kinda-sorta leaning the reverse flow way as it seems (from looking at it) to make sense from a retaining heat point of view. I think I will try and incorporate an exhaust smokebox, since I'm scratchbuilding, just to see what I can do with it:-D .

Just thought I'd share a quick pic of the raw materials.




And




Sorry that one's blurred. That, by the way, is a 600mm x 1000mmm sheet of 2.5mm thick 304l stainless steel, found, with 9 others, in a skip at work! Honetsly, the sheer waste of industry in this country makes me want to weep sometimes Ah well, if they hadn't binned it I wouldn't have it would I?:biggrin:
I've spotted another small gas cylinder on my travels which I may appropriate to make a second, exhaust-stack smoke chamber:-D

Those tanks had flammable gas in them, which onyl makes it worse, I know. Please rest assured they'll be water/soap purged before any cutting takes place, and I'll probably cut with a power hacksaw to boot to minimise any chance of sparks. Thanks for the concern though.

I've PM'd you with the links Norcoredneck sent me (thanks again Norco:-D ) but still can't make up my mind whether to go all out for an offset or build a UDS as I get the impresion UDSs can do a whole smoke on one load of charcoal whereas offsets need re-stoking about evry 4 hours. Plus which I can't see myself doing the kind of quantities you can fit in an offset so don't know whether I'll really need one that big. Are you thinking of building one?

For a second there I thought you were going to say you'd used the mixer drum off the cement truck (d'you think the rotation of the drum'd keep the heat more evenly spread during the cook?:wink: )