please help!!!

[rsavarese]

I'm building my pompeii oven (3") following the strict plans from forno bravo and i just completed laying the base firebricks using the 1 part fireclay-1 part sand......i was just ready to mark my inner circle to be followed the dome and BAM! i noticed that all my base bricks are moving.....i used a knotched trowel like placing ceramic tiles and i'm guessing the right mixture of mortar as said before....is this normal? being that the dome, with a different mixture (fireclay, portland, lime, sand) will be on top and therefore hold in all in place? or did i just completely mess this up?
Any suggestions would be greatly appreciated!!
thanks

[eprante]

RS,
are you planning on putting your soldier course on top of the floor bricks or around the edge. If you are going around the edge,then the soldiers which will be mortared will hold the floor bricks in position. Once you start firing the oven ash will fill in any crevices, you just want them level so your peel doesn't hang up as you are sliding pizza or bread into the oven. I think soldiers outside of the floor is better, then if you ever have to replace any floor bricks they are free to be pried out.
Eric

[DaveW]

It takes a few days for the fireclay/water mix to dry. Then it gets pretty solid. Even still the bricks can move around because they are not stuck to the base. I think you are ok.
Your slab looks great but I don't see the floor insulation. Is it embedded in the concrete?

Dave

[rsavarese]

Hi Dave,
yes the floor insulation is embedded in the slab itself, about 4 inches worth.
are you sure? because those bricks on top, literally no pressure and they are separating from the ~3/8" layer of fireclay and sand mortar i layed.....i do't want them just poppoing off or moving while the dome is resting on them after the fact...i was going to rip it out and start over by adding portland cement in the mixture for some rigidity. A mason told me that in order for everything to stick together rock hard the fireclay needs lime and portland. btw thanks for your input..Riccardo

[dmun]

A mason told me that in order for everything to stick together rock hard the fireclay needs lime and portland

We don't recommend this. Laying your floor in concrete makes replacing a damage brick a nightmare.

Did you wet your floor after you laid it? Or did you trowel on a mixure with water? I'm thinking three eighths of an inch may be more than you need.

[100million]

I think you should think about using the POOR MANS MORTAR for WFO
3 parts SILICA sand 1 part fireclay 1 part cement 1 part lime

or spend alot of money for stop 50

I would not use 1 part fireclay and 1 part sand

[dmun]

I would not use 1 part fireclay and 1 part sand

He's using it for the leveling medium for the floor, not for the mortar between the bricks. That said, Frances used this mixture to mortar her entire dome, and it worked fine.

[100million]

Originally Posted by dmun

He's using it for the leveling medium for the floor, not for the mortar between the bricks. That said, Frances used this mixture to mortar her entire dome, and it worked fine.

I understand this But just takes too long to dry

But it works

[rsavarese]

ok base bricks and first layer of "soldiers" are in....everything seems to be drying nicely....now comes the hard part....the dome. I'm contemplating styrofoam vs sand...i have both just need to decide which way.
thank you all for sharing and for the input. btw i did wet the base before putting everything on.