Fire clay failure.

[brickie in oz]

Fire clay failure.

Many years ago long before I got onto wood ovens, fire clay and all that stuff, I was asked by a builder to build him a fire place, and chimney, no problems.

He was one of the most stubborn blokes I have ever met and you couldnt discus or differ from his "way" whats so ever, anyway, as I get prepared to start building the fire box he gives me a plain brown paper sack with the words "Fire Clay" and nothing else printed on the side.

He told me its what I have to use to build the fire box and roll back, I asked what I mix with it and he said "nothing just water".
I told him it wouldnt set as its basically just mud and as soon as it gets moist from the atmosphere in the air it will be mud again.

I mixed it as directed and all I got was some brown gloop that was basically unusable, I queried the directions only to get yelled at, so I proceeded to build the fire box.

As I was laying the courses you could see the who lot wriggling around and moving, once again I queried only to get more abuse.

I finished off the fire place and chimney but you could see the whole lot slumping very very slowly. I got paid and was gone.

About 3 weeks later the builder rings me up and tells me the whole lot had collapsed, I just laughed and told him it was his method with the fire clay that caused it.
When he asked if I could go and redo it all again I laughed and hung up the phone.

[Tscarborough]

Actually, the old school masons around here do it exactly like that. Basically they make a slurry, dip the bedded face in it and lay the fireplace up. The secret is that you have to have dimensionally perfect brick and basically no joint. I see fireplaces that are 50 to 150 years old that were done this way still working fine. I still sell the fireclay, although I have edumacted most of them, even the old timers, about the advantages of using refractory cement, either home made or pre-mixed.

[brickie in oz]

Originally Posted by Tscarborough

Basically they make a slurry, dip the bedded face in it and lay the fireplace up. The secret is that you have to have dimensionally perfect brick and basically no joint.

Yep, thats how it was done.

Have you any pics of the fireplaces?

[Tscarborough]

No, normally when I am called to look at them it is not for issues with the firebox but of the cap and chimney.

[Lancer]

Ever see anything like this brickie? I was pretty amazed and figured 'if this works I'll be okay with my build.'

How to make a cob oven or clay oven Part three - YouTube

[sandgroper]

This sounds more akin to refractory work which requires a specific brick more suited to kilns than a fire place or oven.

Read Forno Bravos mortar mixes which are more suited for lower temp items than making steel.

Id say you were bullied by the self righteous Brickie

Originally Posted by Tscarborough

Actually, the old school masons around here do it exactly like that. Basically they make a slurry, dip the bedded face in it and lay the fireplace up. The secret is that you have to have dimensionally perfect brick and basically no joint. I see fireplaces that are 50 to 150 years old that were done this way still working fine. I still sell the fireclay, although I have edumacted most of them, even the old timers, about the advantages of using refractory cement, either home made or pre-mixed.

[Lancer]

I have worked for the sort that brickie described, full of themselves, unable to learn through their pride...I know exactly the frustrations brickie was dealing with. To be a professional and be told to do something one knows is wrong is a very difficult position to be put in.

It sounds like brickie's "bloke" was one of these, and must live with the results.