Small dodgey wood heater - pledge

as a take off from Marks huge pizza oven pledge thread, i thought i better get motivated to build my "wood heater / small oven". I had planned to do this for a while, but thought i'd make some forum content? I have no design in mind at the moment, i have browsed a few pot belly stove designs and thought they look like a great idea, but seem pretty expensive, so in keeping with my dodgey cheap theme i thought i should make one.

Plans/Challenge/requirements:

• all steel construction
• rear or top mounted flue thing
• stove top cooking
• possibly a pizza/bread section (sounds complex?)
• Use existing bits of scrap steel
• Must be the ugliest thing you've ever seen
• Cost: $0 (except for welding rods)

budget will probably blow out, same as all government estimates.

 

hah, yeah that's a mates design, they're pretty good, he's made a few different ones, .. but i feel the need to make something more, more.. ugly and square? .. i think gas bottles might be a little small?

mine will be a whole lot more simpler than your project!

 

I was talking to the neighbour last night about fireplaces, and we came up with another million dollar idea, a "one use" fire place/bbq, made from wood!!!
ahh i don't understand why we're not rich

 

Made from wood eh? Sounds like you'd be lucky to even get one use out of it
I would love to see the plan for this one use BBQ. (it's not April fools day is it?)

 

hah, yeah it wasn't a serious idea!

and the great thing is, you'd have to buy another one each time you had a bbq!

 

Well my idea I'd like to put forward is to model it on the Ettamogah Pub.
Have all the sides leaning out a bit and it all out of whack.

If you are really creative (and a good metal worker, sit a car on top like the pub has and have the smoke coming out of its exhaust, or at least some of the smoke as it might be a bit restrictive. Or just have a normal house chimney where the smoke comes from.

I might have just made your simple task quite a bit more complicated.

OR

How about using the front or boot of an old car and build the oven inside it all. Then you could have two 'stacks' coming off the sides as exhausts (just like a truck) where the smoke comes out from.

Or just ignore this frustrated tradesman who has no room to do any of this stuff....

 

Yeah! you could have a few stored in the shed in flat packs, sell them trhough Ikea!

Steve, great ideas! now i'm wishing i didn't start already. I like the idea of making something with a bit of charactor like you have suggested.

But, i already started and now seems all very boring, straight and square. Basic frame is tacked together.

I'm thinking the fire will be on the grill level, then a steel plate under that, then the bread / pizza will sit on the bricks at the bottom. There's the bbq/stove on top and the flue outlet on the top-rear (some tin water down pipe)

 

I can be impatient, want it done now, focused?
I realised i didn't have enough steel so the plan changed a little and my brick pile is being raided again, but i reckon adding bricks is good because it adds thermal mass. By the time i've finished just the steel structure by itself might be too heavy to lift, so i reckon it might perform better as an oven than some of the small commercial wood heaters.
It's hard to tell what the plan is from the above photo but i'm hoping it will turn out ok and will be another interesting feature in my outdoor entertaining area.

There's a lot more to do so it may take a few more weekends.

 

I'm guessing the plan is to enclose the whole thing in to make an oven arrangement.
Do you think you will get enough heat down to the bricks? They just seem a fair way down and that old physics lesson where heat rises is playing on my mind.
I know that pizza ovens are normally on the higher end of hot, maybe higher than 250 degC or even higher. The pizza takes a matter of minutes to cook depending on how thick you make the dough base.

 

yeap i'm hearin ya Steve. I figure "in theory" this is using the same basics as other ovens,

1. Heat source + 2. enclosed area.

Differences might be:
1. location of the heat compared to the food - radiating and circulating heat?
2. shape of the enclosed area - radiating and circulating heat?

You'd also have contained and reflected heat?

But when i think about all this stuff, it's all precentages of efficiency. I'm confident it will work, how well is the question. I whipped up a very basic diagram. The tray is full width, but is short from front to back so there's a gap at the back and a gap at the front when the door is closed so the heat is reflected downwards and is contained.

 

Nice diagrams Stevo. Top job. I get it now.

Not trying to be a pain in the ass but what will stop the heat from escaping out the flue?
I know pizza oven's like the one Mark is building normally have a flue too so they must be ok.
I guess some heat will escape but maybe its like a choke point so not all can escape.

Might need to look into the theory of these things .....

 

There's soo much heat it can't all go out the flue, like even an open fireplace in a home radiates heat and warms the house.

I did some more work today, there's still heaps to do, i have to plate in the back and sides of the fire area, and make a door but i need more steel. I ran out of steel so thought i'd take a break and do some testing. I also ran out of heat beads and wood, ohwell i'll get back to it sometime.

Fire tray slides out....




"Guts" the chicken knows there's food

 

Yeah your right Stevo. Theres too much heat so it has to go somewhere.
It looks like its coming together nicely. Good work mate.

 

yeah, although i'm confident it will work in some way..., i'm not sure about the temperature the bottom bricks will get to and if it will be enough for pizza or making bread. This also depends on the size of the fire. I could make a small fire for slow cooking and a big fire for burning things. I thought I could make a bottom tray/wire rack about 50mm off the bottom which would allow heat under the item? Then you'd have options, like a normal household oven. It's all just a theory at the moment, I don't really know what i'm doing, I'm just making it up as I go ... but I think it should provide plenty of entertainment conducting tests and figuring out what works best.

I'm wondering what the best kind of wood to use is? Not too smokey that my neighbours call the fire brigade, but nice tasting smoke for the food? I know a bloke that sells charcoal so I might get a bag from him. He says it's better than heat beads for bbq because the smoke flavours the food.