A cladding is something that overlays and encases. This is useful for the brick oven because it helps it retain much more heat. It may also help hold the core together more firmly. The recommended cladding for the brick oven is regular concrete (as opposed to cinder concrete), but first, all the bricks are covered with aluminum foil.
This is just aluminum foil that you can buy at the grocery store. The sheets were overlapped some, to form a space-age looking capsule. Then, some malleable wire was pushed into a shape that loosely hovered over the tin foil. As usual, this was to strengthen the concrete so that it should be less likely to crack. The wire that Greg used was some left over bits of animal fencing that he had saved.
As with the pillar leg construction, Greg preferred to save on materials for the concrete forms. He only built it up a section at a time. This also meant he didn’t have to have a lot of concrete mixed at one time, but could work with his own small mixer. In the photo above left, you can see the cladding already in place along the side, as Greg proceeds to work on the rounded top. Don’t get this confused with the outer walls that will show up in later posts.
Once the cladding was finished, it was a good time to make the entry portal to the oven. This space would have the chimney hole and provide a wind break for the main opening to the oven core. This entryway to the oven is made of cinder concrete. When the fire is being started in the oven, the door is left open. That is the only time smoke can been seen coming out of the chimney. Once the fire has heated the oven hot enough, the door is closed to let the heat equalize. When it is time to cook, how the ashes are taken care of depends on the food. For bread, they are completely cleaned out. For pizza, they can simply be pushed to the back and a small fire kept going so that the cheese will brown nicely!
It was deep winter while Greg was working on this part of the oven, so if it wasn’t the weekend, it was dark out there. Nonetheless, he seemed to think it was fun. Kind of like he thinks wandering around in the mountains in the snow, cold and exhausted, while looking for wild animals to kill is fun. :-) I don’t argue. I just check once in a while for signs of life…
The entryway is the only outer aspect where the arch shape is actually seen when the oven is complete. It is purely cosmetic here. A piece of plastic was bent across to connect the entry walls, held in shape by being screwed to cut pieces of 2×4 lumber. A wire mesh was fit over that and around some foam that was shaped with duct tape to form the plug that would create a hole for the chimney. When the concrete arch was cured, clay chimney liners would be stacked over the top of it. These chimney liners would then be surrounded by cinder concrete. The hardest part of forming the arch was getting the rounded plastic/wood form out of the front after the entry roof was done. The concrete adhered to the plastic form more than expected. There were some tense moments with a saw, while trying to cut the wood out.
In this photo, the opening to the oven is closed off by the custom made cement door, which was made later.
There was some concern that the saw would damage the concrete or that the form wouldn’t come out without pounding on it. That would possibly have broken the new concrete arch. Using shims, such as were used forming the fire brick arch may have helped.
It did finally come out, and Greg was able to get busy pouring cement for the outer walls. Read more about that in the next article in the backyard brick oven series!