Oven Floor and Vent Layout

[DimTex]

Apologies in advance but I have looked through many threads to avoid asking these questions:

1.) My insulating layer came out rather "rough" definitely oatmeal, dried oatmeal that is. Rather like a kitchen sponge! I assume this means I need lay a thick enough layer of the fireclay and sand mix to fill in all the uneveness and bed the oven floor bricks properly? Or need I skim and thin layer of mortar to "seal" the insulating layer and then lay the clay and sand mixture atop it?

2.) I am building a 36 inch round oven, should the oven vent be located tangent to the inside diameter of the oven (36 inches) or outside (45 inches). Is there a difference?

3.) If my soldier bricks are positioned along the perimeter of the oven floor should they be mortared to the base/hearth or will they be mortared just to eachother side to side and just sit on the sand and fireclay mixture?

Thanks in advance for your answers I will post photos soon.

David

[Neil2]

Re: Oven Floor and Vent Layout

1) A thin weak refractory mortar layer to level the top to place the fire bricks on is all you need. I used a week 1:5 mortar to sand mix for this.

2) If you can get it tangent at the 36 inch diameter that is fine - usually the inside edge will be back an inch or so to accommodate the angle iron or whatever you are using to support the vent. I tried to keep the entryway depth down to facilitate access to the oven.

3) Either/or. There are two schools of thought on this. My soldier course sat on the hearth bricks and I mortared this joint.