Castable Fibers

[jbuildarkansas]

I installed a Casa2G 100 about 2 months ago and am very happy with it. I've done lots of pizza and some bread and most everything has turned out great.

Today I was inspecting the inside of the oven and notice two very thin hairline cracks in the back piece of the dome. On one of the side pieces is a tiny hole about the size of a small pebble. Could this have resulted from steaming the oven? I've read all about cracks on the outside of ovens but haven't seen anything about cracks on the inside of modular ovens. I cured it per the instructions.

I was just wondering if this is okay or something I should be concerned about. My gut says it's probably nothing but as much money as I've put into this thing I'd hate to think there's somthing wrong with it. I last used the oven two nights ago and it seemed to work fine. I can't see the exterior of the oven since it's enclosed in a stone house.

Thanks for any input!

Jim

[ThisOldGarageNJ]

re: Castable Fibers

My gut says it's probably nothing

Hey Jim, Go with your gut,,, prob nothing,, keep an eye on it if it changes,, otherwise dont worry

Cheers
Mark

[jbuildarkansas]

re: Castable Fibers

Thanks Mark.

[james]

re: Castable Fibers

Hey Jim,

I agree. Keep an eye on it, but it won't be a problem. You can see small hairline cracks on the inside of the dome (on occasion), but relative to the thickness of the dome those thin lines are really OK -- they definitely do not go through to the outer edge of the dome.

Keep cooking and keep enjoying your oven!

James

[jbuildarkansas]

re: Castable Fibers

Thanks, James. That's reassuring.

Jim

[blackjack]

re: Castable Fibers

I built a WFO using a modular kit last Autumn. I recently noticed cracking EVERYWHERE as well as the surface of the dome spalling off in certain areas. Some of the cracks seemed to be right the way through.

I got in touch with the company that sold it to me and sent them photos. Initially they suggested that it was just minor cracking - I told them I expected such cracks but this was much, much worse. I was able to prove it was correctly installed and "seasoned" with small fires first. They looked into it and it seems that a new employee may have omitted to use the fibre they normally mix into the cement.

They are replacing the modular oven FOC and paying to take the tile roof off the housing and reinstall and reinstate.

BTW - I've still been using it. I think a WFO would have to be falling apart before it was unusable!!

[jbuildarkansas]

re: Castable Fibers

Thanks so much for your reply. My oven hasn't suffered any severe cracks so far but I'll keep an eye on it.

[dmun]

re: Castable Fibers

They looked into it and it seems that a new employee may have omitted to use the fibre they normally mix into the cement.

Refractory concrete is an extremely difficult substance to work with. But fibers? I thought that stainless steel needles were standard reinforcement for this stuff. Hmmm.

[james]

re: Castable Fibers

I would note that that was not a Forno Bravo oven. :-)

James

[blackjack]

re: Castable Fibers

Refractory concrete is an extremely difficult substance to work with. But fibers? I thought that stainless steel needles were standard reinforcement for this stuff. Hmmm.

Different countries do things in different ways. I know that some US building practices would not be allowed over here and vice versa.

I'm also pretty sure that the use of stainless steel needles is a fairly new practice and not essential for a safe and effective WFO.

The cob bread oven in my friends farm is nearly 500 years old and still usable. No S/S needles used in that construction.

[david s]

re: Castable Fibers

The stainless steel fibers are called melt extract fibers, even though they're steel. Other fibers used are added to the mix and are designed to burn away at about 160C leaving tiny holes where steam can escape. Maybe these are what was omitted.

[dmun]

re: Castable Fibers

The stainless steel fibers are called melt extract fibers, even though they're steel. Other fibers used are added to the mix and are designed to burn away at about 160C leaving tiny holes where steam can escape. Maybe these are what was omitted.

Huh. Live and learn. Thanks for the info. It makes sense to use a metal fiber in refractory concrete: I'm told the needles are sharp, and have a tendency to poke holes in things like hands and gloves.

[david s]

re: Castable Fibers

Yes they are sharp, but you learn to handle the mix carefully and it's not too bad. The worst is the cost of the things, because you need a fair amount.

[Johnny the oven man]

Re: Castable Fibers

$10/kg is about normal rate.