My previous oven committed suicide going over the railroad tracks last year so I finally got around to replacing it. Actually, I'm under the gun as we plan to use it for an event on May 6. Given a 2-week curing time, I just barely made it! I obtained a new trailer from harbor freight that is rated at 1100 lbs, but still managed to bust this limit. I believe this unit weighs about 1400 lbs. Nevertheless, it is much tougher than the last unit and I have high hopes for it. Working weather has been near perfect. The refractory mortar specifies avoiding temperature below 40, and all week it never got below 45 at night. Eric assisted me this morning with the concrete cladding, which is still wet in the below picture. I used 5000 psi pre mix and applied it at about 1.5" thickness, using a total of 3.5 80lb bags. Can't wait to try this unit out!
The general layout is a layer of 2 x 6's screwed and bolted to the trailer, followed by a layer of 3/4" plywood, followed by a layer of tile backer, then a reinforced slab of concrete about 1.5" thick, then a base of 42 firebricks laid flat (would prefer them laid on edge to better insulate the wood below). The brickwork used up the equivalent of 125 red clay bricks and slightly more than 2 50lb bags of refractory cement. I am using medium duty refractory mortar from Menards and it is not drying real hard. I think I will use the more expensive stuff from the brickyard next time. The dome is poured on top of several layers of aluminum foil and reinforced by a piece of chicken wire.