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The 1st pizza

I manged to bake my 1st pizza on this weekend. As it was baked in higher temprature than a usual electric oven, its surface was very crispy but still it kept moisture in crust and felt soft. After long, devoted 6 months work, my wife and I really savoured its taste, although it was a little hectic to go back and forth between a coffee table in the living and the oven in the garden. I look forward to spending an afternoon around the oven in a warm day in the next summer.

I found a couple of issues. There came no instruction with the oven, I need to do some experiments on the use, especially on firing. Today, I burned fire woods 10-15cm thick, but they took for a while to burn up. I think a quick hot fire is better than a slow, long fire. I will use more kindling size wood next time.

Also, my rake, which is used to pull out coals at the end of firing, is too large. I often scraped the wall around the door. I have to make the rake smaller and need some reinforcement of the door area.

Break-in

It was a cold showery day, but I have been waiting for two weeks the earth oven to get dried. Today is the day to cut the oven door and remove the sand form!

I started a little bit cautiously and dug a small entry on the oven wall. I was scared that the oven would collapse and whole thing would return to just a pile of sand and clay. But, the oven wall was more solid than I expected. It was not so easy to cut the door using a table knife, so I power-drilled many holes and carved out the door.

As wider the entry became, I was relieved that it was not likely to collapse. The 2nd layer was a bit crumble as there are spaces between sand particles, but thanks to straws, it looked that sand and clay firmly got hold together. The 1st layer seemed more tight and well compacted. There was no worry of collapse.

After removal of sand, I stared a small fire in the oven. It was already dusk and a little bit too late to heat up the oven warm enough to cook something. But, the fire is going! It just made me feel warm and happy.

Finished the 2nd layer

This blog is the translation of the one I wrote in Japanese. When I started writing this in English in May, my earth oven project was already in the final stage. I am lazy even writing in my 1st language, and more so in English. If I were to write in this slow pace, I'm afraid I couldn't finish it before my oven would get eroded by harsh Wellington weather. That's why I thought it would be better to start writing from the latest status. Also, I am an impatient person. I hate TV programs which abruptly end in a scene just before the climax with a subtitle saying "See you next week on the same channel, same time". I don't want to put my readers into the same situation.

So, the picture was taken on 16 May, when I finally finished the 2nd layer of the oven wall. This week, I made an oven door from wood while letting the oven get dried. Hopefully, I can cut the door on the oven wall next weekend and start a fire.

In terms of the material, I could not find good soil which contained sufficient clay for COB around Hutt Valley nor Wellington. So I mixed 15% of pottery clay with 85% of sand. I am bit worried how this will work. I'll just have my finger crossed and hope the oven won't collapse when I cut a door.

Foundation

I decided to use river stones for the foundation. River stones look beautiful. Also I like the idea of buiding the oven from something I can find localy. However, I hadn't imagined that it would be such a big job.

On the last weekend, I took around 60 stones home from a local river, which was only enough to make a circle of 1.2m in diameter. Since I chose rather small but flat shape stones that would be easy to stack, a layer of circle is not so tall. If I continue with this size of stones, 7 to 8 layers of stones will be required. If one layer needs 60 stones, 420 stones are required for 7 layers. That's huge. Carrying 60 stones on a hot summer day was a good excuse to drink a bottle of beer. 420 will make me feel like a slave in egypt who built a pyramid.

Searching for Clay

First of all, I need mud, which contains sufficient clay. A gardener told me that the soil in my garden was clayish, so I dug and got small amount of soil from my garden.

Build Your Own Earth Oven talks about how to test whether your soil contains enough clay and how much.
Putting a handful of soil into a water bottle with water and shaking well. If the soil settles within 40 minutes and water becomes clear, it indicates that the soil does not contain sufficient clay. Because particle of clay is finer than sand and silt, usually it will take more than 40 minutes to settle.

40 minutes later, the water in the bottle is still muddy. Seems like the soil contains clay. As another test, adding some water to dry soil, puddling it and it becomes sticky. I can roll and make a snake! Is this clay??

Build an oven

Since I saw a scene of baking pizza in a big old masonry oven on the TV program, Fork to Fork, I was fascinated with that oven and the idea of building such an oven began to raise in my mind.

I ordered a book Build Your Own Earth Oven to amazon for a reference and started my big earth oven project. Earth oven is made of clay, sand and straws. By mixing clay with sand and straws, stacking the mix into the form of a igloo, then drying the object, it will be a firm oven shell.

As for materials, you need sand, mud that contains clay, straws, bricks for hearth and stones which will form foundations for the oven. You can use horse or cow manure for plaster applied on the surface of the oven, but I prefer lime plaster.