80-85% alumina bricks

[Keenan]

So, I have seen that the medium duty fire bricks may be ideal for pizza ovens. I can get a couple of pallets of unused heavy duty kiln bricks for free. Any issues using brick with such a high alumina content? They were used in an animal feed plant, so I'm not concerned about toxicity issues.

[UtahBeehiver]

i used super duty on my build, the only draw back is the bricks are harder to cut and take their toll on diamond wet saw blades. I went through a dozen blades but I went for very tight fit and mortar joints.

[Gulf]

I totally agree with Russell about the the hardness of the super duty brick and the toll it will take on blades that are not designed for cutting them...... Free?..... I would get the the two pallets of free brick and rat hole them, even if I could not use them at the moment. What size (shape) are the super duty fire brick?. I have built retaining walls, fire rings, and an outdoor fireplace out of super duty kiln brick. You just have to figure out where you can use them and minimize the cuts.

[Keenan]

Well there are a couple of different bricks. I was going to get a pallet of flat and a pallet of angled. The flats are around 9x12x2 and the angled are 9x7 and taper from 4 to 3.5. I figured the flat would be good for the hearth and I could cut the angled bricks into 4 pieces to build the dome. They are already angled so that would potentially reduce the number of cuts. But cutting the bricks into forths may negate that. And yes free. They are left over from a plant where I work that has been decommissioned. I wanted to use them if I could because it would obviously drastically reduce the cost to build. I could probably go through a dozen blades and still be in the green. I laid the design out in cad. I think I can cut 50 bricks into fourths (100 cuts) and have enough.

[UtahBeehiver]

So the taper on the 8 x 7 is on the thickness side. You can make it work but it will take some creative placement since the brick face may not be perpendicular to the center of the dome floor pivot point. The floor bricks are only 2" thick so on the thin side for thermal mass, you may need to install a double layer. Also, since these are super duty, I would not cut the floor to fit inside the dome but rather rough cut and leave proud the floor and build the dome "On" the floor. It will save on saw blades.

[Keenan]

I was going to cut those into 4 smaller bricks and use the slope on the top face to help build the curve of the dome. I was going to just leave the sides square. The the grout joint will have to be thicker on the outside for the horizontal curve. I think I should be able to keep them mostly perpendicular to the center. I should have enough to do two layers if needed. That was my plan exactly. I'd just get them close and build the dome right on the hearth. I'm probably going to brick around it when done anyways.