Cheapest and shortest-lived oven

[v12spirit]

My cousin told me that he was planning to build an oven with almost no costs at all, and with almost no effort for building as well. After listening to his ideas, I could refine them so that they SOMEHOW comply with the basics I have learned in this forum. And here is the idea:

A barrel is cut in half so a barrel vault is achieved, a sheet of metal is fixed to the bottom of the barrel so that it is enclosed. The outcome so far is a metal barrel vault oven which I'm sure almost nobody will like on this forum. I suggested to him to bring scoria from the suburbs (it is plentiful and free), and insulate all around the "barrel vault".

The final result will be a wood fired oven that heats up quickly, cooks some rustic food, bread, and pies, and done. But it may live for just months which doesn't matter so long as it is money and effort free.

Any suggestions or comments?

[SableSprings]

Re: Cheapest and shortest-lived oven

Putting a fire in a half barrel will result in an oven, no doubt. Although you'd be able to bake a number of things, you would have to maintain a fire while cooking. That's because with or without insulation, that thin layer of metal will just not store any appreciable amount of heat. Also remember that just throwing dirt/scoria over the barrel is not going to necessarily provide insulation. Yes, the half-barrel will heat up quickly but it will lose it just as quickly...and I suspect you will see more burns on your hands & arms while working around the metal hearth/landing area.

I recently had the opportunity to use a brick pizza oven in Sorrento, Italy. It was made of old brick, low dome, and beautifully built into a hillside...looked great, but didn't work very well. I had a pretty good fire going in it for four days and discovered that I was simply heating up the hillside. On the fourth day, I finally got up to bread baking temps, but there was a 200F drop in temp within 30 minutes! (I actually had to finish the loaves in the gas kitchen oven.) If your cousin has lots of free time, ample wood fuel available, a clean half-barrel, "insulating scoria", and is willing to deal with the heat warping that will occur on the metal hearth and the half-barrel every firing...then I think we'd all be interested in how it works for him...always a gem of information learned from every project!

The two attached photos show the Sorrento oven when we arrived and after I'd cleaned it up and got a fire going.

[v12spirit]

Re: Cheapest and shortest-lived oven

Putting a fire in a half barrel will result in an oven, no doubt.

You got a point there, but I choose scoria because it is a light weight rock full of holes that can trap the air and do some insulation, We may even use broken glasses having the same effect. I was just trying to save him money.

Regarding the thermal mass. My cousine and his family, and also most people, being not exposed to brick oven philosophy, are not familiar with the idea of lighting the oven for hours until it saturates, If he can get used to that and can afford some more effort, we would wrap the barrel with chicken wire, and clad a 1-2" layer of some cement and crushed basalt on top of that, then insulate with the scoria.

However, I think the wood consumption will be less without the thermal mass, but the thermal mass will make him gain heat consistency only. I'll be telling him and we will work according to his requirements.

[hodgey1]

Re: Cheapest and shortest-lived oven

All I can say is go for it. I think I am very lucky to live where I can get the best building material and information for building a WFO. So seeings you and your cousin live where material are at a premium, do what ever you can to make it happen. Best of luck!

[v12spirit]

Re: Cheapest and shortest-lived oven

So seeings you and your cousin live where material are at a premium, do what ever you can to make it happen. Best of luck!

Wasn't like this three years ago..
Thanks for your wishes.

[cobblerdave]

Re: Cheapest and shortest-lived oven

G'day
Using that scoria could be interesting. It's not then efficient form of insulation but the heat will slowly move through it certainly slower than through the steel. So in a way it will act like half insulation half thermal mass? Might not do the full 500C pizza oven temps but to be a WFO non the less.
In in the "give it a go" camp
Regards dave

[v12spirit]

Re: Cheapest and shortest-lived oven

G'day
In in the "give it a go" camp

Happy to hear that.