Homemade Brick WFO

[crazed dawg buck]

I am a ceramics teacher. Making my own bricks for the dome of my Pompeii oven. I have been recycling scrap clay (a really groggy type of stoneware) that would normally be discarded, making my own uniquely curved bricks and using some large open cell styrofoam blocks that have been pieced together to create my shape. The clay is run through a pug mill, will be placed, numbered, dried, deconstructed, fired and then pieced back together in my backyard. I then plan to clad it with cer. fiber blankie, chicken wire, and then do some probably really bad brick masonry for a protective "shell". I would love to hear any suggestions or any ohnoyoudont's......I am a newb. But I know clay and I love pizza!

[david s]

Re: Homemade Brick WFO

It will cost you a small fortune to fire that much mass of clay. Unless of course you can get someone else to pay for the firing. What temperature are you intending to fire your bricks to? Be careful, those thick bricks will take a lot of drying. Try weighing them, if they are uniform in size, to determine if they're dry inside before attempting to fire them.

[Tscarborough]

Re: Homemade Brick WFO

You will also get some shrinkage (as I am sure you know), so you should build your form that much bigger.

[crazed dawg buck]

Re: Homemade Brick WFO

Agreed. The drying time will be long. I will slow fire them, which will help.
I have planned 10 to 12% shrinkage. I more less calculated to get as close to a 32 inch interior diameter as possible. Part of that size decision was clay usage ( I do use some of my recycle clay in class after all) and part was firing. I will incorporate the brick firing (btw firing to about 2200, cone 6) with other project firings. I consider it wasteful and unethical to fire my kilns unless they are packed to the gills anyway! What about my heat holding capabilities? I plan on a cement footer about 12 inches (cold winters) cinder block base with a top made out of a product called AAC block. Supposed to be super heat resistant. Of course fire brick hearth surrounded by regular red brick. Problems?

[david s]

Re: Homemade Brick WFO

A stoneware body fired to come 6 does not have particularly good thermal shock characteristics. It can be improved if you take it to porcelain temps, if the body can handle it, but the cost of firing to the higher temp is prohibitive. An alternative is to fire it really low (around 700 C. A standard bisque firing of around 1000 C is probably too high to get this advantage) and have a coarse open body. I think very groggy hand building stoneware clay would be quite suitable.Italian biscotti ovens are low fired for this reason, also the low fired South American and African pots that will handle direct contact with stoves are also an example of this.The big advantage is the reduced fuel to fire at this lower temp.

[Gulf]

Re: Homemade Brick WFO

Crazed Dawg Buck,
I can't contribute, since I know nothing about firing clay. But, I am interested every technique. I understand making bricks curved to fit your oven. I can't help but notice though, that they are rounded too. It appears that they are rounded on the inside also. Sort of like curved "lincoln logs". Is that going to effect the overall thermal mass? Or, do you have plans for this also?

I'm watching this build with great interest. I do love it when anyone thinks "outside the box" .

[Tscarborough]

Re: Homemade Brick WFO

Low fired is the way to go (for home-made), but you will need to add sand to the clay body to make it work. I have tested, i.e. thrown them into bonfires and the hot fires of the oven, the Mexican brick that we sell and they survive just fine though multiple firings with no cracking or spalling. They are less dense than firebrick, but only by about 20% and they cost 1/3.

[crazed dawg buck]

Re: Homemade Brick WFO

TScarborough, I am going to low fire per your advice. Dave and Gulf, I hope that it all works...the inside will be rippled like a cartoon beehive......hope it doesnt matter. I have been inspired to just give it a go by Kiko Denzers book. I hope it all works!!!!!! Also the clay body is sandy enough to make hands hurt of inexperienced potters. Hope hope hope.

[crazed dawg buck]

Re: Homemade Brick WFO

Have some new pics of the build. iPad will only let me post one pic at a time! Also have the spec sheet on the clay. Fire away on advice!

[crazed dawg buck]

Re: Homemade Brick WFO

Data sheet

[crazed dawg buck]

Re: Homemade Brick WFO

The door and chimney with a bit of the dome top in view. Advise away....let the drying begin.

[david s]

Re: Homemade Brick WFO

If it were mine I'd be making the entry a lot shallower to make the oven easier to work. You could also flare the front of it which will also help. The vent area can be the same if you make it rectangular rather than square ie wider but shallower.

[crazed dawg buck]

Re: Homemade Brick WFO

Awesome, thanks David. I can adjust all of that easily. Not pictured here is also a custom chimney with opposing dragon heads!

[calipizzanapoletana]

Re: Homemade Brick WFO

I'm really looking forward to seeing how the inside of this will look when finished. I assume you're planning on leaving the scalloping of the plugs of clay on the inside? If so- would that effect the heat distribution (spiky interior space vs. smooth curvature)?

Cheers!
-Si

[UtahBeehiver]

Re: Homemade Brick WFO

Crazed Duck,

Both Dave S and I have pottery/ceramics backgrounds and have traded pictures of our work so let's see some of yours, ie the twin dragon heads. I been watching your progress and interested to see if you are going to do just a bisque fire or go to cone 6. I see your clay can go to cone 10 as well. Looks like your formed your brick right out of the pug mill. Like Gulf say, looking with interest on outside the box builds.