The Cob Oven: Version 1.0
I have been wanting to make a cob oven for what seems like forever. I don’t even know how they got on my radar to tell you the truth, but the idea had taken root into my brain and I COULD NOT GET IT OUT.
The theme of this project was “Damn…I can’t believe that worked!”
A friend of mine lives on a piece of property that is right on the water, and her soil is really heavy clay*. She just happened to have a big plie of it laying in her yard that she needed to get rid of so I helped her out and loaded up seven buckets of the stuff.
An insulation layer was put down and then a layer of fire bricks. Sand was mounded to make the form for the oven.
The first layer of cob was applied, which was comprised of sand, straw and the clay. Looking back on this now, I realize that I didn’t add nearly enough sand. My soil is “fat” which means it has really heavy clay content (it’s super sticky) and I needed to have like a one-part clay and three-parts sand to make sure that when the cob doesn’t shrink too much when it dries.
Not too bad, eh? Looks pretty good at this point. Too bad it didn’t stay that way! Another thing I did wrong was to leave the oven uncovered as it was drying in the hot sun. I was thinking that the heat would help, but I realize that clay needs to dry slowly to minimize shrinking, which can cause….you guessed it….CRACKS!
Bummer. However, being all Glass-Have-Full like I am, I am thinking of this as a test run. I learned a lot with version 1.0 and I think that will only make version 2.0 even better! Pizza will just have to wait a little while longer.