refractory concrete recipe and mould plan?

[sonomacast]

I want to build an outdoor oven (Pizza) and basically I have spent a while reading the books and studying the internet and had decided to have a go at using bricks and blocks however I have not laid a brick ever but by trade I am a shuttering carpenter (Formwork) so the obvious and easiest thing to do would be to build my own form (Mould)for the dome.
Concerns I have are, what sort of reinforcement do I use as I guess that steel re-bar would expand with the heat and crack the dome or is this not the case.
(How are the other pre cast domes manufactured?)
Does anyone know of any plans for a form to make pre-cast domes and also how do I make refractory concrete?
Any other info would be greatly appreciated. Thank you

[dmun]

you might want to look at this nearly identical inquiry today.

Refactory cement comes, like quickcrete, in premixed dry bags. I've never heard of anyone making their own, but of course I haven't heard of everything.

[CanuckJim]

Refractory

You can make your own refractory concrete out of LaFarge Fondue refractory cement, pea gravel and brick sand. Just follow the proportions given on the Fondue bags. This ain't cheap.

Jim

[domenic]

Re: refractory concrete recipe and mould plan?

hi i am interested in casting my own oven as well. you were saying that fondue is suitable for making refractory cement,i have looked every were and found no information on it. what is the formula when using fondue ? do you use lime? is portland cement ok to mix it with? do you put reinforcing mesh in the base pore ?
can you plaese let me know as it would be very much appreciated as would any other advise on the topic.

[Dutchoven]

Re: refractory concrete recipe and mould plan?

sonomacast and domenic
Just my 2 cents but...I had never laid a brick in my life prior to building our oven at home and it is doing just fine...and much less to deal with than trying to cast an oven and get the reinforcement right...s-cast we had a builder in CR post a whole thread on his oven...carloswlkr...he was able to purchase tapered firebrick for about the same cost as regular, something I am very jealous of, and with tapers raising that oven dome will be surprisingly easy
All the best to you both, good luck and we are here to help whichever method you choose!
Dutch

[david s]

Re: refractory concrete recipe and mould plan?

The general consensus on a cast oven is to build it in sections to reduce stresses caused by thermal expansion. Also the most common method of reinforcing is stainless steel needles, although there are plenty of people who think that they're uneccessary. Galvanized steel apparently is a no no, some think that the heat will accelerate reaction with the zinc and its melting point ( 420 C) is close to the temps we fire to.

[Wiley]

Re: refractory concrete recipe and mould plan?

hi i am interested in casting my own oven as well. you were saying that fondue is suitable for making refractory cement,i have looked every were and found no information on it. what is the formula when using fondue ? do you use lime? is portland cement ok to mix it with? do you put reinforcing mesh in the base pore ?
can you plaese let me know as it would be very much appreciated as would any other advise on the topic.

Domenic, in searching "every were" [sic] you somehow missed your fellow Auzzies site:

Wood pizza oven Building wood burning brick bread ovens

You might give that site a look.

Also, correct spelling for the product, which used to be manufactured by LaFarge is "Fondu". At least in the USA, LaFarge has sold off that product line.


Good Hunting!
Wiley

[Neil2]

Re: refractory concrete recipe and mould plan?

Don't use portland cement based concrete. Don't use reinforcing steel.

Both give up their strength in the temperatures your oven will operate.