new to the forum

[brickie in oz]

Re: new to the forum

then I will insulate with red clay brick so I think this is my best option without spending thousands.

What do you think of that plan.?

Cheers Grant.

Clay bricks are not insulators, also if you have clay bricks why not build the oven out of them?

[UtahBeehiver]

Re: new to the forum

Why don't you post pics of the bricks you have to work with? Brickie makes a good point about clay bricks. Going back to Bookemdanno's build, he used solid reds on his dome.

[clinch]

Re: new to the forum

Thanks for the advise on the bricks,

If you want to see one of the storage bricks its in one of the pictures sitting on the top of the stand ready to go under the floor.

I had a good talk with the wife about it last night, her thoughts were that if I cant find out whats in the storage brick,"she wouldn't eat out of it"

And that leads to other questions about whats in a fire brick that is chemical.

So here it is I think the final plan.

storage brick under the floor, then clay tile for the cooking floor, then clay brick for the dome.

The other good think about red clay brick is there is plenty of them around after the earthquakes, so it should be my first choice really.

So I just needed some expert advise from the forum, and the wife to tell me what I should have allready known!.

Cheers for know, grant.

[brickie in oz]

Re: new to the forum

If you have access to lots of pressed clay bricks I would be mucking around with bricks that have unknown qualities.

[david s]

Re: new to the forum

Neither heat storage bricks or solid pressed red clay bricks are designed to perform at WFO temperatures. They are both designed for other purposes. Either may be suitable for an oven and could possibly work quite satisfactorily; on the other hand they may fail. Many builders have reported that their solid reds have worked ok, others have found they have failed, because the clay composition of bricks will vary enormously. You have a better chance of success with a brick made of clay than one which contains Portland cement. Fire bricks are however designed to withstand the temps we use.

[clinch]

Re: new to the forum

Hi there David,

I appreciate your advise, I have a problem with the fire brick, they are far to expensive if you read my posts and they are made in china.

As far as the clay brick goes, it really does depend on what tempertures you are trying to reach, it says in the forno bravo pompeii instructions that thay are fired at 2000 to 3000f, so they will take some heat say before stress 800cell.

I fiqure if you heat them slowly they should be fine to cook some food, considering most food cooks in a fairly ineffecient steel box at around 200cell.

So it all comes down to how long you want to wait for your food and or pizza to cook.

I will also be making my roof and back of my oven housing removable so if the bricks fail I will just repair it or build another.

Red brick are plentifull, fire brick are not in this country.

Cheers grant.

[Toomulla]

Re: new to the forum

The oven temps will 800F not 800C 800 F is about 400 C
I agree that fire bricks are costly in North Queensland (aust) I paid about $5.50 I expect a well fired solid brick or clay paver will see you out

[clinch]

Re: new to the forum

Its good to find that I maybe on the right track, I will throw some money at the floor though, with fire brick.

Cheers Grant.

[david s]

Re: new to the forum

Grant,

I wasn't trying to steer you away from using the solid reds, just giving you the facts. If i were in your position I think I'd be using the reds too. But just be aware that they may fail. The temp they are fired to is only one factor. Their ability to withstand thermal shock time and again and the rapid rate of temp increase is your main enemy. If you fire carefully and only raise the temp 100C/hr it will probably be safe, but no one heats their ovens that slowly in the real world.I would be looking around Christchurch fireplaces (if any are still standing) and taking a good look to see if solid reds are used for the hearth. If they are and they aren't spalled then you are probably ok to use them. If the hearth bricks all seem to be firebricks then you can probably assume that the local Christchurch reds proved to be unsuitable.

Dave

[clinch]

Re: new to the forum

David, thanks

You have very sensible advise, what Iam going to do, with reds I have is dry them out slowly and test them in the open fire underneath, Iam going to use them in there anyway.
I know it will be nothing like an oven but it may give me an idea of there properties.
I can select different types and test them.

Iam looking into a soap stone supplier in our country at the moment, it sounds like that could be ideal for the oven job, depending on cost.


Grant.

[david s]

Re: new to the forum

Putting the red bricks into a fire is hardly going to tell you much. Fire them a hundred times might though, but I doubt you'd want to go to those lengths. That's why I suggested you check out local old fireplaces. Presumably most of the bricks in Christchurch have come from local brickworks using similar clay deposits. I have seen plenty of old fireplaces in Victoria, Australia, that have badly spalled red brick hearths, so would assume that those bricks would be unsuitable. WFO builders in South Australia however report that their solid reds work fine in their ovens. Can only conclude that the clay in different areas has a different composition. Unfortunately you won't really know if they're ok or not. Just build it anyway.

[clinch]

Re: new to the forum

Hello David,
You have convinced me on the fire brick, I will go that way for the dome , I have a large wet saw for stone so I will cut the fire bricks in thirds they will be 75mm thick getting my costs down a bit, I think 75mm is enough for the brick, I will then build up with fire clay then insulate.

This will have to be better than red brick at 100mm.

Thanks again for the help I will keep you posted, when I get into it.

Grant.