Slip Joint or not?

[bricks]

Hi Out there,

I will be building an outer arch out of Bullnose bricks 9". I'm leaving the half bricks out to create a toothing which will be filled with 3" of blanket 1" of vermiculite/fondu then 3/4" of render 41/2" of the Facade bricks will overlap 41/2" of the firebrick inner arch should this overlap be a slip joint would appreciate any thoughts.Bricks

[brickie in oz]

Re: Slip Joint or not?

The outer arch looks from the pic like it will be in contact with the heat and flames?
If so it will crack with the heating and cooling cycle.

[bricks]

Re: Slip Joint or not?

Hi Bricky in Oz,
I'm thinking the same. Perhaps a 5mm gap between the to arches as both are selfsuporting.Or because its the furtherist from the fire a bed of fire clay or ramming puttey between the two could work.bricks

[brickie in oz]

Re: Slip Joint or not?

a bed of fire clay or ramming puttey between the two could work.bricks

Or some ceramic rope?

[david s]

Re: Slip Joint or not?

About 6:1 vermicrete will work well too.

[bricks]

Re: Slip Joint or not?

Thanks for the info David S.Does this mix have normal cement or fondue. Bricks

[bricks]

Re: Slip Joint or not?

Hi Bricky in Oz,
Just thinking that if i cut a channel into the internal and external bricksto take the rope it would act as an anchor and a great seal still allowing say a3mm gap to difuse heat transfer to the facade. Bricks

[david s]

Re: Slip Joint or not?

Thanks for the info David S.Does this mix have normal cement or fondue. Bricks

I just use Portland. It is in a slightly cooler area and seems to work ok. Fondue is a bit of an overkill IMO when used outside the main oven. It is also way more expensive.