kiln shelfing for cook surface

[waynebergman]

I want to put in the center of my WFO over my cooking floor a 21" diameter round Kiln shelf. It is 3/4" thick and I think it would be more like a high duty brick than my medium duty bricks in place now. I have all medium duty firebricks in my build so not sure how this would act for a cook surface for pizza but wanting some input from those that may know. I have some chips and errosion on my floor and thought this would be a good solution to kind of clean things up and also it may be nice to have the cook area for pizza's to be slightly higher that the rest of the floor so ashes dont slide into pizza's so easy.
So a couple of questions.
1. Is this a good idea, not sure if this Kiln shelf is food safe and if the high duty rating on the stone is better or worse than my med duty now being used.
2.Should I mortor it in place or just sit it losley on some ashes?
3.Do i need to go through the gradual heat up process with it in place as i did when oven was just built or just fire it up and go for high heat right away?

thanks for this ....wayne

also since I have last visited this site I have completed my roof for the oven if anyone is interested in checking out the photo album link.

[dmun]

Re: kiln shelfing for cook surface

Kilns Shelf Basics - Basics of Kiln Shelves
There are two entirely different kind of kiln shelves. The high alumina ones seem like high duty firebrick, and should be fine. The corderite, or silicone carbide ones I don't know about. They were invented since I had anything to do with pottery.

[waynebergman]

Re: kiln shelfing for cook surface

thanks dmun....yes they claim to be "high alumina" so am I correct in assuming they are food safe?

[waynebergman]

stone now in place

photo here shows this kiln shelf in place in my oven. Wondering if I should have a bed of fire clay under to help with pressure points so it doesn't get cracked or maybe I should mortor it in place? Any ideas on this? thanks wayne

[dmun]

Re: kiln shelfing for cook surface

Wondering if I should have a bed of fire clay under to help with pressure points so it doesn't get cracked

It can't hurt, particularly if it's rocking. Wood ash would work as well. As far as strength, those suckers are strong. They go up to bright red heat supported by three little kiln stilts. They also can be banged around by teenage art students without visible damage.

[Les]

Re: kiln shelfing for cook surface

Wayne, What is Kokopelli made of ? - Very cool! I find it curious because the Hopi is not very close to Canada.

Les...

[waynebergman]

Re: kiln shelfing for cook surface

Les I bought the Kokopelli from a flea market in Mesa Arizona for 15 dollars. It is made of mild steel with a patina made to look like copper. The artist would not tell me the process used for patina. After I mortared the piece in place covered it with the same sealer I used on the exposed agragate. Seems to be holding up ok.

[ThisOldGarageNJ]

Re: kiln shelfing for cook surface

Hey Wayne,
Just checked out your pictures... Great build.. Love the door and the river rock..

Beautiful job

Cheers
Mark

[altamont]

Re: kiln shelfing for cook surface

Earlier in the post there was mention of kiln shelving made of silicon carbide. It is typically very expensive due to manufacturing costs. Silicon carbide is noted for its very high thermal conductivity, excellent thermal shock resistance and its strength. There should not be any problem using any type of clean kiln shelving in WFO's.