Castable Floor????

[ddchef]

Hey Everyone, I just bought a used WFO trailer and need to replace the cooking floor. Currently there are 5-6 tiles that are only a 1inch thick. I was wondering if anyone has made a casatable floor for their oven. I would like to try this method so i can get the right thickness that i have room for.

Any thoughts, suggestions or comments?


thanks

[dmun]

Re: Castable Floor????

Firebrick is better and cheaper. Is there insulation under those tiles?

[ddchef]

Re: Castable Floor????

yes there is about 2 1/2 inch layer of some kind of sand mixture

[james]

Re: Castable Floor????

It sounds like you are in good shape. Firebricks will work great, and you can work them nice and level in the sand mixture.
James

[dmun]

Re: Castable Floor????

yes there is about 2 1/2 inch layer of some kind of sand mixture

Sand, or a sand/fireclay is a good leveling medium for firebricks, but it's no insulation. While you're digging stuff out stuff you may want to make some room for insulation board.

[james]

Re: Castable Floor????

That's an interesting question. What do you do if you don't find any insulation?
James

[david s]

Re: Castable Floor????

I think that a cast floor for a mobile oven has advantages over firebrick floor. A number of pieces are more inclined to rattle to bits, this is also true for the dome. My mobile oven has a one piece cast floor, although now I make the floor in two pieces to reduce the tendency for the floor to crack down the middle.

[ddchef]

Re: Castable Floor????

I know there is no insulation underneath the sand. The cooking floor sits ontop of the sand and the sand then sits on top of restaurant grade stainless steel. Underneath the stainless steel does get warm, but that heat does a second job which is heating a 6 gallon water tank for hand washing so i'm ok with that.

David, i was thinking the same as you less for movement in two pieces, so less chances of chipping. What did you use to cast your floor and how is it working out?

[james]

Re: Castable Floor????

The cast floor question has been floating around for a while and I come down solidly on the side of using firebricks. Firebricks are compressed and kiln fired to become vitreous, making them much more durable than any castable. Plus they cook great.

Mainstream castables do not put up with the thermal shock and abrasion that the cooking floor sees, and they will definitely crack and spall. There are ultra low cement castables (96%+ alumina, silica and titania) that you can find, but they are expensive, hard to work with, use only 5 1/2% water and require a vibrating table. I think that is something your should leave to the pros.

Will an ordinary cast floor wear out with heavy catering use? Yes.
James

[david s]

Re: Castable Floor????

ddchef,
I cut out the shape of the floor from 5 mm plastic and then split it down the middle Then made a band 3" high which runs around the two plastic pieces and held in position with a clamp. A piece in the middle which separates the two pieces and I then cast this with a layer of vermicrete, so there is 1" insulation cast into the floor and the rest with castable reinforced with stainless steel needles. It works pretty well and leaves you with two managable pieces. The needles do a good job of strengthening the material but are expensive.

[ddchef]

Re: Castable Floor????

Ok so i've decide to go with the firebricks, but i have a couple questions.

First the bricks are wet, using these to replace the floor will this pose any issues, such as steam when i fire it up? Will this effect the old oven dome?

Second do i have to cure the floor or can i just fire it up to temp and get cooking?

thanks guys

[enz]

Re: Castable Floor????

Check out http://www.fornobravo.com/forum/f28/...rill-2207.html

This oven is still going strong after 50 some odd firings. The beauty of the mizzou castible is that the thermal properties are exactly the same as fire brick.

Enz

[david s]

Re: Castable Floor????

DDCHEF,
Sorry have missed this thread for a while. Yes, you will need to fire the thing slowly to drive out the moisture in those bricks. Fire bricks are not vitrified and therefore not waterproof, they are porous so you need to remove that water slowly.