Refractory Mortar Question

[Balty Knowles]

Re: Refractory Mortar Question

last night I made 2 slugs of high temp mortar & stuck a couple of off cuts together so I could test the strength. After curing for 24 hours I was able to crush the mortar back to powder in my hands.

This eliminates my thought of over wetting the mortar when I sanded the floor last week & suggests that one of the ingredients is no good. I'm guessing its the Calcium Aluminate.

Any suggestions, are my ingredients wrong? Otherwise I should I go back to the store to let them know, I'd hate for some poor schmuck to finish an entire project before finding failure.

Regards

Balty

[Balty Knowles]

Re: Refractory Mortar Question

I called the technical manager at Caluchem today, they manufacture Lumnite. He told me my formula is way too light on the Lumnite he suggested the following mix for my oven mortar

2 parts sand
2 parts Lumnite (Aluminum Silicate)
1 part Fireclay

Omit the lime altogether, says it has no place in a refractory mortar.

The lumps in the Aluminum Silicate are very bad, I need to go back to the brickyard & inform him of the problem.

I will test this formula this weekend & let you know the results.

Rgds

Balty

[cristaldi]

Re: Refractory Mortar Question

Ok, after reading this thread I am confused. Are you all talking about two different mediums for construction?

One 'make yourself' and Two 'use Refmix'???

TIA

[asudavew]

Re: Refractory Mortar Question

Yes you can buy premixed high temp mortar.

Here's a link

http://www.fornobravo.com/store/RefMix-p-16154.html

Or you can make your own.
Using:

1 part cement
1 part lime
1 part fire clay
and
3 parts sand

There is also another recipe to make your own. It is supposed to handle higher temps and closely resemble refractory mortar


1 part calcium aluminate
1 part lime
1 part fire clay
and
3 parts sand

[Unofornaio]

Re: Refractory Mortar Question

Fire Clay does not reach its strength untill FIRED.

[james]

Re: Refractory Mortar Question

Not many people are mixing their own mortar with Calcium Aluminate (Lumnite), so it is not a big issue, but Balty's posting earlier in this thread on the better mix for lumnite is very useful.

2 sand
2 lumnite
1 clay

James

[That's Amore]

Re: Refractory Mortar Question

Hy guy's I am new and would like to know if the refmix is exclusive to forno bravo or can I purchase this anywhere. If only at forno bravo how do I go about ordering it. I am building the pomeii 42" and I have the FB board and am just in need of the proper morter

Thanks

[That's Amore]

Re: Refractory Mortar Question

How do I get this refrax mortars from forno bravo I can't seem to find it