White Oven

[Faith In Virginia]

I've been thinking of a white oven. I'm looking for plans and the particulars of building one. Can anyone point me in the right direction.

Thanks Faith

[brickie in oz]

Re: White Oven

I should imagine it would be fairly simple to build, its an oven within an oven so the hot gasses can flow around the inner oven.

Opening at the front underneath and a flue exiting at the front on top.

[Faith In Virginia]

Re: White Oven

That's what I was thinking...BUT....like so many that come here to build a pizza oven it's all so simple at first ...then...you get the rest of the story. So I would like to see some plans and assess the good and the bad that comes with it. I would like to build off what is already known about white ovens.

Had a great batch of bread today. Between my new mixer and proofer I've noticed much improvement in my bread. The nice thing is that by controlling proofing temperature and humidity I can predict when my sourdough will be ready and that really helps with oven timing.

[Faith In Virginia]

Re: White Oven

More thoughts on what I'm thinking. You all know I make bread so I was thinking that a way to recharge the oven without a new fire in the oven chamber. I'm thinking a white oven would be very inefficient and burn gobs of wood and take a long time to heat. There is another oven type that has the burn box separate from the oven chamber but that is not great for bread because you want to trap the moisture coming off the bread while baking. So perhaps a hy-bread (Pun intended). I think the construction should take into considerations of flow of gasses from the oven chamber and oven masses in what area as well as what needs insulation if you have a more constant heat source. Any thoughts

[Dmendo]

Re: White Oven

Hi Faith, I'm thinking in a kind of black oven and been investigating a lot of published info about the matter. Basically is the same but the white oven avoids combustion gases to be in contact with the baking chamber. So you have to make two ovens, one inside the other. The external ones can be made of isolating refractory bricks or boards (as the kilns uses ceramic fibers in the fire side). You can get a lot of info in the masonry heaters association (Fornobravo is member of them): The Masonry Heater Association Home Page - Information on masonry heaters, manufacturers, and masonry heater builders
Masonry Stove Builders - masonry heater manufacturers
All the ways, for white opperation I reach the conclussion that the most efficient way to do it is starting from the Tepluska oven design and adapt it for a white opperation. A lot of info about this kind of oven:
Krestianskaya Teplushka - Pyromasse
Although the Teplushka concept is intended for dual purpose oven plus masonry heater, is clear it can be adapted for only oven purpose isolating all around.
Regards

[shuboyje]

Re: White Oven

One thing that make designing a white oven much harder then it would seem is the issue of diverging flows that was bought up in this thread:

http://www.fornobravo.com/forum/f8/e...lue-17453.html

To get around this you would have to route all the gases up to the top of the oven, then have them diverge into different paths and descend down over the oven and converge back into a central flue and go up and out. Would be pretty complex.

For your goal I would personally look into a Guillard Oven. Easier to build, gets to higher temperature then white ovens from my understanding, and you can easily and cleanly re-fire it between batches as needed.

[SCChris]

Re: White Oven

Faith, I'm just curious, how much bread do you want to bake at a time, and how many bake runs?

Chris

[Faith In Virginia]

Re: White Oven

I have no idea!!! LOL What I do know is that in my 42" Pompeii with 7.5 inch of thermal mass in the walls and floor looses quite a bit of energy when I put in 18 lbs of cold wet dough. So after two runs of dough my temp starts to drop and I'm down to lower temp baking and no longer have that supercharged effect for significant oven spring and that expected crust. Loading bread at temps above 550 burns the outside and in inside is not cooked. Temps in the 425 range takes longer for the bread to bake and the crust is not as dark or crispy. So I was thinking of an oven that could be recharged without having to start a new fire in the box. I have time before I would start building one so for now I'm just kicking tires. Perhaps I'll just have a second oven. But if you have any ideas I'm ready to kick them around for consideration.

I've also been thinking of a quazi white oven where you have a secondary fire box and when you need to recharge the oven you could move some dampers and direct the hot gasses through the interior of the oven. Then shut them all back when your at your desired temp.

Also thanks Dmendo and Shuboyje your links were great and gave me lots to think about.

[brickie in oz]

Re: White Oven

I've also been thinking of a quazi white oven where you have a secondary fire box and when you need to recharge the oven you could move some dampers and direct the hot gasses through the interior of the oven. Then shut them all back when your at your desired temp.

I dont think Ive seen your build pics, if I have Ive forgotten it.

Is there some way you could light a fire underneath your hearth at the moment, or is it all insulated?

[SCChris]

Re: White Oven

Interesting, If you load at 500F for the first load where do you end up after allowing the oven to equalize? What are your oven floor temps for your second round of baking? What I'm wondering is if you can add more mass in your floor and / or more insulation around the oven that would give you baking time?

Chris

PS you need a Max Poilane oven in miniature.. I think I remember seeing one of these in action and that it was a white oven.

http://www.youtube.com/watch?v=u4RiJs1a92U

Nope it's a black oven. At 2:34 in the video you see a cast iron fire directing flue removed and a vessel of water closing off the oven from the fire. Really interesting oven design.

[shuboyje]

Re: White Oven

It is called a Guillard oven. I agree this would be ideal. Bread isn't my thing but if it was this is what I would have built. There is a build online where a le panyol oven is built as a Guillard.

[Faith In Virginia]

Re: White Oven

Okay that is the oven of my dreams!!! Screw the miniature I like that one. I like how you can add steam in that port. Pull that pot of water out then put that directional piece back in ...how cool.

My oven is good but if I want to step up bread then it's just not enough. I know my floor is a bit lacking in insulation 3.5 inches of vermiculite/ Portland but the rest has 4 inches of ceramic. I have thermocouples all over my oven so I know I have good heat saturation. I have preheated my oven the day before so that the oven can regulate over night then give it another firing the day of the bake. I have to be careful not to get the oven too hot else I'll be burning the bread if the average temp is 800 or so.

But if you think about it 18 lbs of dough at 75% hydration for easy math is 7.7 pounds of water that's almost a gallon of water pushed into the oven. Do that twice with two loads of bread... that eats up the stored energy in a hurry.

[SCChris]

Re: White Oven

Yep, that oven is pretty slick, never mind the bread..
Back to your bread, can you replace the oven floor so you have 4.5 inches rather than 2.25? In my oven I could roll the bricks and get 4.5 or put in splits and have 3 3/8 thick.

Chris

[TropicalCoasting]

Re: White Oven

Have you seen this before?
Rocket Stove Design Base - Bread Ovens

[Faith In Virginia]

Re: White Oven

Chris, no can't do. I have 3.5 not 2.5 of insulation and the lower set of bricks are imbedded into the vermiculite. so on the floor I have one set of brick laying flat and the next set on edge. I have thought of separating the the vermiculite layer from the base layer and sliding the whole oven onto some insulation board on a new base.

The rocket stove is interesting. The plans are involved so I will dive into them later. Thanks