Got these firebricks, how should I build a pizza oven with them?

[david s]

Coming along nicely .. =)
I decided to make a support in the center of the concrete slab, and using 90 millimeter of leca, and 50 millimeter of calsium silicate board to insulate the under the oven ...

Any input on the necessity of side support for the arch? I´m thinking of insulating the sides with calsil board and then cast a square ring of rebar reinforced concrete around the 10-15 centimeter lower part of the arch ...

Yes, that should work. Search for barrel ovens on this site. There are a number of builds that detail how they've either buttressed or steel braced their barrel ovens.

[Fizz]

Bought a few new bricks for the floor and finished the part in the far end of the oven.

Started mocking up the entry arches and the flue ... input, anyone? If I use one curved brick för the flue the cross section will be 100 by 300 mm, that has to be enough, right?

[Fizz]

One brick deep that is. See photo .. =)

[Fizz]

Moving along..

[Fizz]

A few more pics, but minor progress .... Still open for input on buttressing/bracing of the "barrel arches" .. necessary or not?

[Fizz]

Fizz,

Welcome to the forum! That is an interesting shape for fire brick. A barrel vault seems to be the best choice. From the stamp in the pic I would have guessed that they were an ultrahigh 65% alumina. However, I did a quick search of those markings and found Höganäs Bjuf Refractories. A click on their products, link to a page shows a BJUF.SX (line 4) as a 35% alumina alkali resistant firebrick. So, I'm guessing that the "36.27" stamp is the actual alumina content (much easier to cut with a wet saw than 65%). From reading their page they have been in the business for a long time. You may be able to contact them with some questions. Aside from all that, clean and dry them real good so that the mortar will stick, and have fun .

For the sake of online information searchability (!?) I think I found out what the numbers are. I bought some new floor bricks (Also Bjuf SX), and they were stamped "17 05" so I figure its the manufacturing date, year and week number. (The old ones are stamped "86 27")

[Fizz]

A little more progress...

[Fizz]

Closed the dome yesterday .. Just one arch left to do ...

[Fizz]

Finished the FB floor, and the insulating FB heat break, and cast the first part of the buttressing.
And a pic of mocking up the entry arch ..

Been kind of quiet in this thread, so I´ll guess that means I´m on the right track ..

[david s]

By the look of your pics the end walls are built beside rather than under the vault. This presents a problem when the vault expands wanting to push out the end walls. As you have also created separate arches rather than staggered joints there may also be problems there. Some steel bracing should hold it all together. Here's one solution.
https://community.fornobravo.com/for...288#post207288

[Fizz]

By the look of your pics the end walls are built beside rather than under the vault. This presents a problem when the vault expands wanting to push out the end walls. As you have also created separate arches rather than staggered joints there may also be problems there. Some steel bracing should hold it all together.

Thanks for the input! I wonder how the staggered/non staggered joints affect these type of curved bricks ..

The back wall is built under the "first arch", but the last one, before the entry arch, is only supported by half an inch "from below" by the entry arch .. I guess we´ll see what happens ...

[Fizz]

Removed the forms...

[Fizz]

Almost finished the roof by now .. spending most of my time making pizza, rather than building though .. =)

[UtahBeehiver]

Quite a common ailment of WFO builders.

[Fizz]

Bought an IR thermo gun and started reading the different temps in the oven ... Most temp recommendations around the web are pretty general, and I´ve noticed that my floor temp is hard to get over 400 c ... If I fire my oven til the dome starts clearing in the "middle" of the oven, where my cooking surface is the floor is well above 400 c, but when I push the ember to the side and back and use smaller pieces of wood and "less fire" and the cooking begins, the floor cools down to 300-350 c .. As long as I´m the only one making pizzas and baking them it´s fine, the floor heats up btw pizzas, but when I do multiple pizzas in a row the floor cools down to fast ..

Any ideas?