Fondue and vermiculite dome!

[Chickensoup]

Hello everybody,
I would like to commend you on a great forum, i've been sculking around for a while i finally decided to join you all as i'm in the middle of an oven build, and desperately need some advice.
I've just had my wages cut due to...........need i say! and money is tight to finish my oven, i originally wanted to use firebricks on the inner dome and a rendered exterior, but the cheapest brick i've found are ?1.12 each( i need 300) then theres the thermal blanket and fondue and vermiculite etc.
The thing is, yesterday i was chatting with my nearest refractory supplier and he suggested casting a 4" fondue/vermiculite dome over a sand shaped mould and once its dry dig out the sand and hey presto a heat resistant and insulated oven.............................................. .................................................. .......Will this work?

yours Chicko

[david s]

Re: Fondue and vermiculite dome!

No. The inner dome needs to be very dense, so don't use vermiculite here, it will reduce the density and strength of the inner dome. Use the vermiculite outside the dome and under the floor, but don't waste your money on mixing fondue with it, you only need enough portland cement (10%) to make it stick together.

[Lars]

Re: Fondue and vermiculite dome!

What is fondu?

[dmun]

Re: Fondue and vermiculite dome!

he suggested casting a 4" fondue/vermiculite dome over a sand shaped mould

This can't work. Insulating concrete won't retain enough heat to do any cooking.
Just as an oven won't work without insulation, it won't work without thermal mass inside.

What is fondu?

A type of refractory material found in other English speaking countries. No need to worry about it unless you're shopping for materials in Canada.

[Chickensoup]

Re: Fondue and vermiculite dome!

Thanks for the advice lads, i'll just have to wait and save then. I'll upload some pics of my work so far, in a while.

Chicken