British BBQ Society Forums

Hey folks I'm currently designing and building an offset reverse flow smoker. The fire box is almost done, made out of 6mm steel plate all welded and bolted together.

For the cook chamber the largest diamter vessel I can get is a 47kg propane cylinder. Will this be ok or do I really need a huge tank as seen on some of the U.S. sites

Advice muchly appreciated

Oh, I'm interested in this, I've been looking in to this occasionally for when I win the lottery or get a pay out for being awesome and can build my own.

Looking at all the 'Build threads' there are always from Americans and they seem to use different size / shape gas tanks than we do. So after a bit of Googling a while ago I found some 'standard tank measurements' to find what might be the diameter they would be and went from there.

My idea was basically that I would have to get sheet steel rolled to the diameter I want. I am sure there are standard sizes for steel tube but I can't find out what they may be, I was getting ignored when I rang around because I'm only after a meter or two of pipe instead of being the big bucks orders people would normally make.

The table below was just a starting point for a rough size which I felt would be good, and if I could get a rough price for these at least I could start to plan and see how much an example build would cost.

So, in all cases I was thinking of getting sheet steel rolled to 635 mm diameter, which would require a length of 1995mm then the you just need to know the width you want and obviously the thickness of the steel. I had an engineer mate plug the numbers in to his calculator to get the approx weight. I think the thickness here was based on 4mm (perhaps 3mm)

hi, there, i have just built an off set smoker from a 47kg bottle, i cant see a problem with the size to make a reverse flow. you'll have to let me know how it works out.

How do you find it?

I've got a few 47kg gas bottles but felt it wouldn't be wide enough to get enough food on

the 47kg give a good cooking area, could be bigger, i can fit a 20kg lamb on it, or around 12 racks of ribs of 5 good pork joins

That's awesome guys. The diamter on a 47kg bottle is 14 inches. Americans typically use LPG tanks, the type you have if you don't have mains gas, these are typically around 20 inches diameter or more.

Americans seem to have an endless supply of such tanks and usually over engineer everything to accommodate very large quantities of meat, they probably ain't seen the prices here

This now gives me the confidence to cut up the bottle and crack on

Mike, do you have any pictures you can post up?

I wouldn't say over engineered, they are probably 4-6mm thick which helps with heat retention and they will be less prone to environmental factors.

I did start to build a grill from a 47kg bottle, I had an afternoon to do it and it had the end cut off already so it was supposed to be a quick build, not a quality one and it was built to that standard (or lack thereof), I didn't have enough metal to build the legs for it to stand on at the end ha haaa so it got put down the side of the garage

il post picks this week end, make sure you fill the bottle with water before you cut it, or things get interesting

mike.read wrote:il post picks this week end, make sure you fill the bottle with water before you cut it, or things get interesting

Cheers mate, looks interesting and cutting bottles is no issue I've done

I've just designed one at my work.i found this to be a help full guidehttp://www.feldoncentral.com/bbqcalculator.html. i made mine out of 5mm steel all role and pressed. helps when i have to source a large amount of laser cut steel that is rolled and folded. then I'm going to get it powder coated with special heat proof powder. i used solid works to design my reverse flow smoker. now just to build it before summer comes.