My latest precast oven, struck today

[sonomacast]

I have been putting in an hour a month for some time now on this oven. I set out to build the perfect precast oven using the corect formulas I have learnt from this site and along the way. Internally the floor is 1050mm in diameter (41.3 inches) The walls and dome roof are 75-80mm (3") thick, the floor has yet to be cast but shall be 75mm (3") thick, The flue maintains 50 square inches though it starts off a rectangle and ends as a circle (8" dia)

the height of the interior dome is 90% of the radius of the oven floor?
The Door opening height is 63% of the dome height?
The area of the flue is 10% of the area of the door opening?
The ideal door is 22" wide at the dome?
The flue should be 10% (area) of the area of the doorway
the ideal floor is 2 1/2" thick?
The minimum thickness of refractory (cast) concrete is 3"?

And also I have cast the segments so they interlock, 5 triangles, one capping stone (round top) the porch and a piece above the porch.
Something I am very proud of. Hope you like it

[sonomacast]

here are some other photos

[GianniFocaccia]

Sonomacast,

Great-looking oven! Not sure if you're asking questions in the second paragraph, but your dimensions are consistent with proven designs. If I were to cast an oven I would model it after yours. The only thing I think I'd do different is go with either a firebrick or soapstone floor.

Great job so far. Very nice interlocking castings.

John

[Les]

Very impressive! James, you have competition.

[david s]

If you are planning on casting a floor as well I suggest you do it in a few pieces as well. A one piece floor is likely to develop cracks due to uneven heating, mine did, i now do it in two interlocking pieces. I like the design of your flue gallery, nice and shallow for easier access.

[sonomacast]

I am casting the floor into 8 pieces, 6 equal triangles and one round centre piece and a seperate piece from the door back to the entrance to help with insulation (heat leak).
Evwrything is segmented for ease of assembling however the porch weighs far too much for one person to lift..at the moment the whole dome weighs 400 kilos (880lbs) without the floor.....

[sonomacast]

Originally Posted by GianniFocaccia

Sonomacast,

Great-looking oven! Not sure if you're asking questions in the second paragraph, but your dimensions are consistent with proven designs. If I were to cast an oven I would model it after yours. The only thing I think I'd do different is go with either a firebrick or soapstone floor.

Great job so far. Very nice interlocking castings.

John

I was thinking of casting the floor in segmented refractory cement but laying a slab of granite or marble on top for a super smooth finish

[dmun]

granite or marble on top for a super smooth finish

Granite or marble are not good cooking surfaces. They will spall and crack at oven temperatures. Soapstone is the only proven high-heat natural stone.

That said, firebrick is nearly ideal. If it's laid properly it's more than smooth enough.

[brickie in oz]

I put some marble in a large fire ages ago to see how it would stand up to the heat with the intention of using it for an oven floor, it turned to dust.

[lwood]

Nice job Sono. That's a lot of work making the forms. What receipe did you use for the refractory....or is that proprietary? Looks like you have like you have thought of everything and the refractory looks solid.

Have you decided on the floor yet?