The sunny spell continues – but it’s highly unusual for mid-september so we had better get our oven done quickly before the rains set in. Today we achieved a big milestone by completing the basic structure: we finished the insulation layer and outer cob shell. All that remains now is plastering and some repairs to the inner surface.
It’s quite an impressive structure – larger than most backyard cob ovens we’ve seen. But it’s about the smallest you can make it if you want to do any real baking. 4” of thermal mass and 4” of insulation are just adequate; and the baking chamber isn’t huge either.
Today we started applying finish plaster. The base is Klamath Yellow clay mixed with sand at about 1:3 ratio. We also added a good measure of boiled flour paste: it makes the plaster adhere better to the surface and harden up nicely when dry. After putting on the first coat it already looks much more finished.