New steel for a wood burning stove

[GeorgeB]

Would new steel be terribly expensive, compared to the use of a modified gas cylinder? One advantage is that it would allow the construction of a square stove.

How thick is the steel used for a gas cylinder?

I just obtained a quick quote for a 2m x 1m panel of 3mm thick steel and it was £32 + VAT. I have no idea if 3mm is enough to stop warping under extreme heat, or if that price is typical. Does anyone know, please?

 

[Wozzaaah]

They vary between 3 and 4mm George so 3mm should be ok, after all, pressed steel bbq's are very thin and they can get darned hot!

 

[Arsonista]

I've just made one from a very old bottle. While I was cutting it and welding, I thought that if I ever made one from sheet it would be 5mm thick. Just my opinion mind.

 

[rtbcomp]

If you're worried about warping fabricate the stove in sections that sit on top of one another or are very lightly bolted together to allow movement as the stove expands and contracts.

 

[GeorgeB]

Thank you for your input on the panel thickness and other considerations. I guess somewhere around 3-5mm should do it, then, plus a method of fabrication which allows for expansion and contraction. I need to price this up to see if it's remotely feasible. It needs to be a lot cheaper than stoves from Machine Mart, for example, to be even worth thinking about. Just taking my sample of 2m x 1m x 3mm for £32 + VAT, is that about what you'd expect to pay, or should I be able to find similar panels at a lower price?

 

[pedrobedro]

Our wood burner stove in the house is made from 10mm boiler plate but cheap stoves as sold by Machine Mart are made from metal such as you are describing. I wouldn't go any thicker than 3mm for a home made one simply because it will be hard to cut unless you have burning tackle or a good plasma. If your stove is getting hot enough to warp or glowing red you are putting too much heat into it.

 

[rtbcomp]

My cheap & cheerful Clarke one is cast iron. I got it red hot when I left the damper open and forgot!

 

[Hitch]

£32 isnt particully overpriced for joe public.

How do you plan on rolling the barrel George?
That could probably cost you at least half as much as the sheet again if you have to get it done for you...

 

[GeorgeB]

How do you plan on rolling the barrel George?
That could probably cost you at least half as much as the sheet again if you have to get it done for you...

My idea was to cobble together a cube type shape, rather than a cylinder, so I'm not planning on any bends. Cutting thick panels will be a challenge, though, as pedrobedro has pointed out. The welded joints should be easy, given panels at least 3mm thick.

 

[snowcat]

1/4" M/S would be fine if you went thinner id be tempted to add some stays if its square......

 

[Arsonista]

£32 for a 2 x 1 isn't bad, but if you want to go thicker get it designed first and then get it priced as cut blanks. Make your design so that it 'nests' nicely on a stock size sheet.

 

[GeorgeB]

1/4" M/S would be fine if you went thinner id be tempted to add some stays if its square......

Your suggestion and Wozzaaah's, thanks, that "pressed steel bbq's are very thin and they can get darned hot!" makes me wonder if it's worth building a low cost, prototype version out of 0.8mm car body steel, reinforced in places with square section bars, or whatever. I'll soon find out if such thin plate will work and, if so, whether my chimney arrangement, smoke extraction, heat output and the effort/cost of sourcing fuel are all worthwhile, or more hassle than it's worth, in practice.

 

[GeorgeB]

From the oakleysteel.co.uk web site page on boiler plate:

"ASTM A 516 is a carbon steel designed for use as a pressure vessel plate in low and moderate temperature service. These plates are usually used in boilers and welded pressure vessels where improved notch toughness is required."

I don't know what 'notch toughness' is but I guess boiler plate is mostly to do with high pressure. I trust it would be quite expensive and probably OTT for my DIY wood burner.