Sunday was a nice day to work outdoors. The guys spent the day in the garden, Jordanne took care of the animal chores and leveling out the ever growing pile of compost that accumulates in the animal enclosure and I spent the day preparing and putting on the finishing coat of plaster on the cob oven.
I made a plaster mixture (3 parts sand, 1 part clay with chopped straw) that Ray told us about on his last visit. Then I completely re-plaster the top of the oven and the bottom. As you can see, the top oven is a different color from the bottom. We thought that a “two tone” oven would look prettier, not to mention that the bottom being a darker color means you can’t see the smoke marks from the firing chamber. I covered the oven with a tarp overnight and Monday I was at it again mixing up more batches of plaster to add another coat.
Trying to figure out a better way to make this last coat of plaster to be nice and smooth, I sifted the straw and sand through an even smaller screen to get any big pieces/rocks out. Then before adding the clay to the sand I mixed some hot water into the clay to break it down, making it the consistency of pudding. Then I added the clay pudding to the shifted sand and mixed thoroughly, lastly adding the finely shifted straw. The straw acts as a binding agent to keep the plaster from cracking. This technique seemed to work much easier and made a great plaster mix!
Cob oven’s done!
I tried working using gloves to protect my hands, but I like the way the clay makes them feel soft afterwards; however, my palms are scratched up because the abrasiveness of the sand in the mixture. Also putting the plaster mix on with your hands you get the feel of the mix better and the texture looks natural.I am happy to say that after two days of plastering – Mission Accomplished. The cob oven is done (well that is the plaster dries nicely and doesn’t crack!) Then Ray says that all we have to do is apply a coat of boiled linseed oil for added protection.
Last night had to run outside and tarp the oven – didn’t want all the work washed away! (Who’d have thought that there would be rain in September?)