Geodesic Pizza Oven

[MatarazzoDesign]

Hi All,

I've seen some threads/ posts on geodesic ovens and wanted to get some feedback on my idea.

Using a geodesic plugin and SketchUp I was able to make a large pizza oven dome. The inside diameter is about 42". This allows for 13" equilateral triangles (which should be large enough for my pizza peel) and 11.5"x13" triangles. Please see the attached screenshots.

I was thinking about making the two types of triangles out of Terracotta. Make a triangle block mold, wedge the clay, press into the form and voila you have a 2" thick triangle block. We have an electric kiln and could fire a few tiles at a time (maybe 4-5 depending on how many spacers and shelves we have).

From here I'm a bit confused with how to construct it. I assume I would just use a refractory mortar to set them in place. Possibly use a sand mound or wooden jig to keep the side walls in place while the mortar sets.

I'd really like to know what you think of this idea. I remember two very detailed posts on geodesic pizza ovens (though one of them failed because the clay was not dry enough). The concept seems great, I just don't know how well it works in practice. One thing I haven't looked into is Terracotta as a pizza oven. I'm sure it has been done before, considering it's history. I'm not sure if 2" thick Terracotta walls are good enough for an oven, or if I will need to add insulation.

Thanks in advance; I appreciate your help!

[Les]

Re: Geodesic Pizza Oven

You should ping Dmun. He's been down that road and would give you the best advise.

[MatarazzoDesign]

Re: Geodesic Pizza Oven

Hi All,

I brought my geodesic dome into SolidWorks and continued to work on it. While I will only need 2 sized triangles, I might need as many as 4 different ones because of the angled sides.

I've attached two PDFs with a quick drawing layout for the dome and the equilateral tile block. I color coded the blocks in the layout.

I'd really like to know what the community thinks of this design and the material choice (about 2" thick terracotta). I'm going to the ceramic supply store in Lodi, NJ to ask about terracotta and get their thoughts on the right clay mix. As a side note, has anyone had any luck using kiln shelves as a cooking floor?

Thanks in advance!

[stonecutter]

Re: Geodesic Pizza Oven

Besides cool factor, I see no advantage over traditional coursing.

[jeeppiper]

Re: Geodesic Pizza Oven

I have a couple of thoughts.

1. I have no particular experience with terracotta other than my chimney. My concern would be using the large triangular facets. Thermal stresses and particularly thermal cycling on those large, rather thin 2" triangles might be a source of cracking. I think most folks build their ovens with half-bricks (firebrick) which make for 4"-4.5" walls. This

2. Your entranceway seems small 13"w x 6.5" high. I think my 42" oven is 20w x 16 high. This small entranceway might make it difficult to build your fire and manage the inside of your oven. You also might want to include a small lip around the entrance to the oven chamber to allow for a door.

3. Kiln shelving? What is the material? Just make sure the material is durable. The floor of your oven will take somewhat of a beating. Also, using a large thin piece for a floor might be a source of cracking. Your floor is going to have a rather large temperature gradient. It will be very hot underneath the fire, and much cooler elsewhere. This difference will cause thermal stresses that can crack your floor. Making your floor out of firebrick allows for differences in expansion.

Just some thoughts....

[UtahBeehiver]

Re: Geodesic Pizza Oven

This will be interesting to watch your build. Be sure to post pics. Kiln shelves are typically made from high alumina ceramic or cordierite and normally no thicker than 1" which probably will not give you enough thermal mass for heat retention. You could add some fire brick underneath. Unless you get a deal or have access to surplus kiln shelves, fire bricks are probably cheaper.

[deejayoh]

Re: Geodesic Pizza Oven

Looks cool, but to my way of thinking - any build that starts with "first step, make bricks" has some serious drawbacks

Dmun made a geodesic design, but he didn't make the bricks. IIRC He cut them down from firebrick

[stonecutter]

Re: Geodesic Pizza Oven

Looks cool, but to my way of thinking - any build that starts with "first step, make bricks" has some serious drawbacks

That's the only way my internet buddy Erik builds. Of course, masonry supply yards are tough to get to in Tanzania. He builds awesome groined vault homes...all handmade, and fired by hand.

[MatarazzoDesign]

Re: Geodesic Pizza Oven

Hi All,

Thank you for your advice. I visited the "local" ceramic supply store in Lodi, NJ and told them about my idea. He recommended this. My reasoning for making terracotta "tiles" and assembling an oven is that I have no experience with brick laying/ cutting or casting concrete. I have had experience with clay (though not exactly like this).

In my mind it seems easier to build a wooden mold (or a large cookie cutter) and make these tiles. Then fire and assemble them (hopefully with as little mortar as possible). I assume I would then have to use some insulating blankets or built a surrounding housing to help retain the heat.

The kiln shelves were an idea but I see what you are saying about their thickness. And yes, firebrick is cheaper for the floor. Though I am curious about possibly casting refractory cement in triangle molds.

My wife thinks it would be easier (and therefore more likely for me to finish) to build a mold out of blue foam and cast the oven dome in place (or dome sections). This would still involve a firebrick cooking floor and entrance. What are your thoughts?

Would you be able to enlighten me with some links to other builds that I can look into? I sent Dmun and edschmidt PMs because of their builds. If you can think of anyone else I would greatly appreciate it.

Thank You,
Dan

[UtahBeehiver]

Re: Geodesic Pizza Oven

If you are interested in cast ovens, looks at Mikku's or Iron Pony's thread. There are a couple more but so look under "Other Oven Types".

[MatarazzoDesign]

Re: Geodesic Pizza Oven

Thanks, I'll check them out. Stupid question, but does "beehive" refer to your oven style or are you an apiarist? I ask because I'm working on an observation beehive at work.

Thanks again.

[UtahBeehiver]

Re: Geodesic Pizza Oven

Oven style, but I let my neighbor use a part of my property to place a couple hives and a they drop off some honey each year. The bees are pretty low key unless I get closer than about 5 feet from the hive. Plus Utah is known as the beehive State.

[Vichi Lobo]

Dan, did you ever finish the schematics for the geodesic pizza oven? I am also interested in a winter project and casting three dimensional triangles seems to be a good one.