Sunday, July 24, 2016

Going in for the Landing

Now that the dome is complete, I’ve got to create the landing area in front of the oven maw and the chimney system. The landing area will be just in front of the ash slot and the ash slot will be underneath the chimney. There will be a lot of weight on the front arches with the chimney, so I’ll be adding some fairly solid buttress components on the front sides.

I did a dry stack on the sides to get an idea of final heights for base of the chimney “arch” support. I then cut some concrete block and laid it on the oven platform in front of the ash slot and across the front span of the oven. Next I mortared bullnose bricks across the top for my landing.

I built up the sides of the oven front entrance to the point I wanted the arch to start. Once the bullnose bricks were mortared in, I took common brick and laid it to provide some significant lateral/buttress support. Being an overachiever, I also ran a pieces of rebar down through the brick holes and mortar to help keep the side mass from shifting. With the sides now solid, I laid out two brick arches that would span the entry. The back arch was made of firebrick and the front was made with common reds. In looking at my completed arches, I concluded that 1) not only am I spatially challenged, but apparently I have trouble making things square and 2) as a total brick novice, I shouldn’t have been doing the final arch work (my first) by flashlight.

So after the mortar had set on the arches, I concluded nobody but me would know how bad it looked (...hmmm, then why did I take these pictures and now post them?) I next started creating the smoke gathering chamber that leads into the chimney. The template to create this flue “throat” was something I saw in the Forno Bravo forum. It involved cutting two sections of 8" diameter clay flue pipe at an angle and joining them together. The result was a section of flue that was wider at the bottom than it was at the top. The joining at the top was back to the original 8" diameter. This throat piece was mounted on top of my entry arches and serves as the smoke collector for the oven’s upper chimney segments. I laid firebricks across the top of the entry arch sides, joining with the throat piece at the apex. Thankfully, the buttressing I had added on the lower sides of the arch did their jobs and the oven’s chimney system is still standing.

With the oven landing and chimney arches set and the lower throat piece of clay flue section in place, I was ready to build up the oven front. Brought up the sides and the arches to form a level top and "pleasing" front. Put a chimney cap with cinder/ash screening in place and decided it was time to start curing the oven.

Again, it's good to know how many novice errors can be covered up with a little effort "up front".