DIY castable refractory

[david s]

Re: DIY castable refractory

You did a fine job building your moulds, I was in no way being critical of your work.. However, they must have taken you many hours to build and prepare for casting. How many castings have you produced from them since? A sand castle mould is so fast to make that you can complete the sand part of it in around an hour. If the intention is to create a single casting this method is far less labour intensive. Builders can make up their own minds how to do it.

[mikku]

Re: DIY castable refractory

Well we disagree on another topic.

If a job is worth doing, why not try to do it right?

And, how many people know the first time around exactly what they want?

If you make a decent form, you can modify it if you do not like the first results. But with your "so easy- sand method, you have to start from scratch--or more specifically dirt".

So the "so quick" now becomes "so slow"! And there is no consistency.

But that is IMHO!

[david s]

Re: DIY castable refractory

If you are going through the effort of making good forms, don't waste your time with homebrew castable...buy the real stuff. It is not that expensive--my entire dome only took 9-25kg bags of castable for a 80mm thick 750mm inside diameter dome. I'd never screw around with a homebrew under any circumstances...if you value your forming time!

Unless you are planning on making several castings from the one mould, creating "good forms" is a waste of time IMO. It is easier to make a single cast over a sand castle, so quick and easy.

[mikku]

Re: DIY castable refractory

Equivalent of 252 US dollars, probably cheaper where you are. Japan is usually two to three times higher than anywhere else.

[michelevit]

Re: DIY castable refractory

how much was 9-25kg bags?

[mikku]

Re: DIY castable refractory

If you are going through the effort of making good forms, don't waste your time with homebrew castable...buy the real stuff. It is not that expensive--my entire dome only took 9-25kg bags of castable for a 80mm thick 750mm inside diameter dome. I'd never screw around with a homebrew under any circumstances...if you value your forming time!

[deejayoh]

Re: DIY castable refractory

I think for a pizza oven you want calcium aluminate cement instead of portland, and firebrick grog instead of clay (as aggregate). I think most instructions call for SS needles for strength as well.

[david s]

Re: DIY castable refractory

I've cast an oven with the following recipe.

1 part lime
1 part fireclay
1 part portand cement
3 parts sand.

Mix well dry.
Add minimum amount of H2O.
Cast away.

Add some polypropylene fibres to the mix to assist in removing the water more safely.
Should probably add some stainless steel needles at 2% by weight too. They're called "melt extract fibres" in the trade.

[michelevit]

Re: DIY castable refractory

I've cast an oven with the following recipe.

1 part lime
1 part fireclay
1 part portand cement
3 parts sand.

Mix well dry.
Add minimum amount of H2O.
Cast away.

[hamaxx]

I am sure this question has been asked and answered many time, but I have done many searches and forum reviews without any luck. I am interested in a mix design for home made castable refractory concrete. Interested in casting some panel sections for a wood oven project. Any help would be great. Thanks Rod - Wisconsin USA