baking bread

baking breadpaerlite insulation nearly donebread

I need help. I bought a little pizza oven form portugal. In hopes of baking bread, I insulated it with a 4 inch layer of 5 to 1 pearlite/mortar and stuccoed it. It looks great and I guess holds heat well. I baked bread in it before I insulated it and had a good result---once [pictured]

I am flying blind. I have never had a brick oven and have no one around with any experience to help me.

I will enclose pictures but the oven is a dome and about 40 inches across.

When I have a fire going it can read over 700 degrees inside but the outside feels like there is no fire in it at all. Good insulation yes???

My problem is that the oven cools down really fast. After reading some forum entries it appears I'm not firing it long enough to heat the oven interior.

Is a smaller, longer fire better? Can you bring it up to temp faster with a biger fire?

Any help would be appreciated on any front!! Bruce 

5 comments

Hi Bruce,

 

it certainly sounds like you haven't fired the oven for long enough to allow the mass of the oven to absorb sufficient energy to maintain heat for baking.  The 700 degree internal temperature you mention is to a degree irrelevant as you're just waiting for the mass of the oven to absorb energy and you can't accerlerate this beyond a certain point.  Try firing it with a moderate fire for three or four hours, then rake out and bake.

 

best of luck with it

 

David

David,

Thanks so much for the help. I realize that I haven't fired the oven long enough. The outside bearly gets warm so I know it's holding heat I'm just not letting it store enough. I'm new at this and I'm going to try exactally what you said. Bruce

I can tell you than this oven is not so good for bake bread, I have a oven with similar design but inside 1,2 m diameter, this ovens are design for multi cook propose, meats, and pizzas. The thermal mass of this oven is insufficient and the heart of the oven it`s so thin too, I fire every day 8 hours, it`s good insulated but don`t have enough thermal mass (good insulation don`t mean have thermal mass). One time I finish to bake pizzas all morning I can`t bake a bread with a good results, and in this time the oven is so hot, but fast lose the temperature.

I found than this ovens designs it`s not good for bread, the dome is so much high and the door so big. It`s design for a easy fire with pizza, a lot of air flow.

After a lot of test I decide build an Alan Scott type.

 

you can see my oven in this link http://sourdough.com/oheso-cafe-bakery

 

 

Bruce

 

Some of the Modular ovens that come out of Potugal are fairly good....others are fairly bad. Most of the time the problem with heat loss is the chimney or vent is located "inside" the dome.....the correct position is outside the dome in the entrance arch. This can be addressed by fitting a damper to the vent....your oven doesn't seen to have any chimney, so it can't be that. If you can't feel any heat on the outside of your oven when firing, then the wall of your dome must be working. The problem could be twofold. The design of your dome looks too high. The height of the dome should be half the diameter of your oven....in affect an exact half circle...or less. The other thing could be under floor insulation. If the floor is refractory concrete then it needed to be installed on top of a layer of vermecrete (vermiculite, cement and water)..... or even a layer of thermolite blocks laid on flat.

 

It may be a lot of bother but you could help both problems by laying a layer of fire-bricks (lay them on top of a mix of powdered fire-clay and sand) on top of your existing hearth. The doorway seems high enough for you to be able to do this without compramising the area needed to feed the bread in. The height of your doorway should be 63% (ish) of the height of your dome.....this looks like it is correct, so even after laying an extra 3" on your floor...you should be still in that 63% ball-park figure.

 

These are only a few suggestions, as it would be such a shame for you not to get the best out of your modular oven.

 

Terry

I appreciate all the help. If I can solve the problems with my oven it might help others. Thanks again, Bruce