Friday 12 September 2014

Adventures in Cob - part 2

Where we learn what we did wrong...

We made a door, based on more mathematical workings out we knew based on the radius and height of our pizza oven what width and height the door needed to be. I had checked that a pizza tray would fit through that gap and looked at my bread tins too.

We had found an old mortar board which we thought would make a perfect door so cut that down to size and then drew round it it make a paper template. We then used that to cut around into the cob to create the door.

door space cut out

This is actually far scarier than it sounds - it involved cutting a hole into our carefully constructed cob dome and removing part of it. You can't wait for it to be properly dried out as a) it would be a real bugger to cut through inches of fully dried out cob and b) it won't properly dry out all the time it is filled with three wheelbarrow loads of wet sand. Well not in my lifetime anyway.

Next we checked the door fitted in place. It did. This was good.
Next, according to all our books and internet research we had to scoop out the wet sand from the middle. All a bit 'moment of truth'. Scoop until you hit the newspaper around the outside of the sand leaving only the outer layer of cob.

It was a lot of sand. It took a while.
This is where we learned our lessons. What we should have done is either - scoop out quick and then put the door in to assist in propping up the doorway hole. Or leave the sand in for a longer period once the door was cut out. Or - my personal favourite not cut the door hole into the north facing side of the pizza oven which never gets the sun shining on it and so therefore does not dry out and means the wind is not getting blown in and the oven is not drying from the inside out either as the entrance is both sheltered and in shade.

The consequence? A slightly dented dome where the cob has slipped a little and is no longer quite big enough for the door to go in. The options to remedy the situation? 1. Pull it all down and start again heeding the knowledge that hindsight has granted us and moving the door to the east or south facing side. 2. Hope it dried out soon and then trim off the excess so the door fits and maybe simply for aesthetic reasons fill in the slight dent with some more cob - it will mean that inside we have a slightly non-domed bit but I am fairly sure this will not impact adversely on the cooking quality of the oven and from the outside no one need ever know.

At the moment we are planning on going for the second option - Fingers crossed it continues to dry out and we are able to do that fairly soon. We may try and light a small fire in there to assist with the drying out process.

4 comments:

  1. Mistakes or no, I still think it's really clever! :D

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  2. https://www.khanacademy.org/about/blog/post/95208400815/the-learning-myth-why-ill-never-tell-my-son-hes

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  3. The video is worth you watching. You could have made it yourselves! X

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  4. I'm looking forward to reading about the outcome of this experiment!

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