Budget Build 36"

[stonecutter]

Re: Budget Build 36"

Your bricks are what they called Dough Boys, when they fired the bricks in way back when they used to stack a whole bunch together in a kiln then fire it, the bricks in the middle didnt get fired too well an were called Dough Boys,

Interesting term, considering were they will (may) be used. Around here, under fired brick are call Salmon Brick.

[brickie in oz]

Re: Budget Build 36"

One of the forum mods needs to limit image sizes to 800 pixels, it will avoid what has just happened in my last post........

[brickie in oz]

Re: Budget Build 36"

Interesting term, considering were they will (may) be used. Around here, under fired brick are call Salmon Brick.

Its an English term that was transported here along with the inmates.

[david s]

Re: Budget Build 36"

There is evidence to suggest that lower temp fired bricks with a groggy body may actually be better performers for an oven.

Probably trial and error is the best method. The temperature the bricks are fired to and the composition of the clay body are the two most important factors and the seller of the bricks is unlikely to be able to give you this information.

"Fireproof bodies is a popular and indefinite term which simply means those which have a relatively good resistance to thermal shock. It covers two distinct kinds: (a) ordinary ovenware of various kinds ranging from soft-fired porous earthenware to the well known types of ovenproof stoneware, and (b) flameproof cooking ware able,like metals,to stand direct contact with the flame. In this latter class may be placed the soft-fired unglazed cooking pots of West Africa, made from bodies of an extremely coarse and open texture;and in the same class but at the opposite end of the scale, flameproof porcelains fired* between 1400 C and 1500 C. Between these two extremes, it seems rather doubtful whether a satisfactory flameproof ware can be made in the stoneware range, 1200 to 1280 C."
Michael Cardew, Pioneer Pottery
In the case of the African pots they are fired in a range of 600 - 670 C.
However it is highly unlikely that you can get commercial bricks fired at temperatures as low as this.
In the case of house bricks they have to be fired high enough to partially vitrify so they become waterproof enough not to let the weather through the walls. In the case of firebricks, they are usually designed for much higher temperatures (double what we fire to) so they don't melt.

[cobblerdave]

Re: Budget Build 36"

Gudday
Well what constitutes enough clay to make a pizza oven work?
Cob? Not fired enough by normal oven firing temps to survive normal wheathering from rain and storms.
And firebrick ? Overkill on the temp requirements for pizza building.
Inbetween? .... What is useable from common brick and paver?
I don't know. I tend to graduate back to the original plans which says simply if given the choice between building an oven and not building an oven for lack of firebrick build an oven with brick commons anyway!
Bevan your the man calling the shots. You have got a bit to do yet , a slab to form, an insulation layer to lay, plenty of time for other things to change.
Regards dave

[Laspaz]

Re: Budget Build 36"

Yep Dave you are right, plenty of time yet. Either way I am pretty committed to these bricks, mainly because of my very limited resources.

I have been out this morning and split a few with my bolster, no crumbling, just 2 or 3 hard sharp sections. Not that that proves anything!

I am going to have to use these for the dome. Worst case scenario, I have to rebuild the dome at a later point in time when I come across better bricks at a good price. That means I get a practice dome build under my belt and when the rebuild comes around, I am better prepared. Also the project at that point is much lower cost and everything from the oven floor down would stay, even the outer arch and chimney if I am lucky.

Or the clay bricks might be fine and dandy. I haven't come across anyone that reports a mass fail with lots of spalling and crumbling, even from those using house bricks with holes in them. And I think I read that the spalling isn't likely to happen when I want to cook, but later when cooling?

Stay tuned for the results

Thanks for everyone weighing in.

Bevan

[Laspaz]

Re: Budget Build 36"

I think it was DavidS that said hitting a brick with a hammer is pointless and proves nothing. I would like to confirm his hypothesis with my experiment detailed below.

12lb sledge hammer head dropped from waist height onto various bricks.:


First up is the real deal commercial refractory fire tiles:


Second is the proper marked firebricks from a firebox:


Third is a solid cream brick from the 1950's. These are pressed and a potter I was talking to this week (not selling anything) said they have some refractory properties to the clay they were made from and he uses them as firebrick.


And last are my crumbly orange bricks. I smashed two, one held together well (this photo) the other crumbled badly (photo next post)


Next post to continue....

[Laspaz]

Re: Budget Build 36"

Ok, so I would like to submit a comparison of the cream solid pressed bricks I could keep an eye out for if you guys really feel they will be significantly better and more suitable for the oven.

First off the second red brick that crumbled badly:


Here are the two options side by side:


Close up of the cream brick interior after 12lb sledge:


The red bricks weigh 7lbs (3.2kg)
The cream bricks weigh 8lbs 6oz (3.8kg)


So I can save up and get the cream bricks for about $1 each if you think it's the best road to take...

Cheers,

Bevan

[cobblerdave]

Re: Budget Build 36"

Gudday Bevan
It's seems to be the nature of things people tend to post their successes, and nevertheir failures. I have yet to see pic with a spalled brick , plenty of cracks but people wear those as a badge of honour!
It's good your going into this with you eyes open and a good attitude!
I mentioned "QLD Pizza Oven" thread before if you want to read Worbs comment click on my avatar it will take you to my page and Worb has left a visitor message about his 3 yr old brick common oven. How knows he might respond to a post on his thread
Regards Dave

[Laspaz]

Re: Budget Build 36"

Dave, that is a pretty good endorsement from Worb! I wonder what the quality is between solid reds that you guys have and what we have here. I feel like my orange (red) brick might be inferior but the creams are more on par? Who knows..

I think whatever I use should work... Hopefully.

Lets see if my wood stand can support the 400kg on concrete I have ready to go on it first.

Thanks mate,

Bevan

[cobblerdave]

Re: Budget Build 36"

Gudday Damon
Sorry there are precious few examples of common brick ovens on the forum. So I've used Worbs oven as an example.
One thing I did notice in those photos is those bricks had been in contact with the ground. I don't think the constant moisture is a good thing.It would make them crumbly.
I would consider how the bricks were stored and in the very least if stored on the ground,only use those that were on the top. You could use any rejects as paving in front of your oven.
Brick commons are not that common up he in Brisbane most of the older housing is hardwood construction. There are some good old pressed commons to be found. For the money though I would go for pressed clay pavers. Although you have to be careful there too as there are a lot of cement pavers about and they are definitely not suitable.

[Laspaz]

Re: Budget Build 36"

All my bricks are rain wet but only the bottom ground layer will be saturated.

I got the concrete slab done while I was losing my mind over stupid bricks!



Should I give it a mist with the hose every now and again or just let it do its thing?

Cheers,

Bevan

[ATK406]

Re: Budget Build 36"

Keep it damp for at least 3 days (a week is better). Concrete builds strength with moisture.

[shortnstout]

Re: Budget Build 36"

Hi guys, don't want to hijack your thread but as another kiwi trying to come to grips with building a pizza oven I have a question about fire proof materials. I built a furnace for melting aluminium and I used a refractory cement I bought from a foundry supply place in Auckland. I was wondering if the same could be used for a pizza oven? It would need to be reinforced so it didnt colapse, so my thought would be to construct with ordinary brick and plaster with refractory cement. Thoughts anyone.

[brickie in oz]

Re: Budget Build 36"

Thoughts anyone.

Start your own thread.