Brick type decission to be made

[jwnorris]

Re: Brick type decission to be made

Interesting floor. I like the concept - the larger the pieces, the better the surface. This is the best of a modular along with a brick dome.

J W

[Bacterium]

Re: Brick type decission to be made

Thanks jwnorris - I'm not sure how I will go with the red bricks next to the fire tile as far as different expansion rates?

Neil mentioned these local red bricks are generally quite some years old - mine are the "Hallet" brand (this company still exists locally).

I was talking with a very experienced brickie mate recently about the variations we have noticed with solid reds (I was a sparky for 13yrs so spent plenty of time mounting equipment on/in brick walls).

A couple things ??.. Some are very crumbly or "sandy" like and are softer & dull looking. We figure we have only seen this sort in the houses 50+yrs old?..unless the bricks were ?recycled?.
At the other end of the spectrum (which is what I?m using) the reds are much harder and slightly glossy. Maybe some of the more knowledgeable on here would have an idea why????I?m guessing this is something around firing temps, silica (or whatever) content and other materials.

[CanuckJim]

Re: Brick type decission to be made

BT,

Not sure this will help or not, but when bricks were actually formed and fired on a building site in the olden days, the kiln was built with rings of brick. The bricks on the inside, closest to the fire, were the hardest and used for exterior applications. The bricks in the outer rings were termed "salmon," because of their lighter color. They were considerably softer and used for interior walls where they may or may not have been plastered. Before the relatively recent advent of high efficiency brick kilns, these differences persisted. So the crumbly ones of a lighter color were probably fired at a lesser temp.

Here in Ontario we also have "marl" bricks made from very dense yellow clay. On the exterior of 19th C houses that used them, they are still in very good shape because the clay made such hard bricks. We also have the red variety, but they're nowhere near as durable. In England, I've seen indigo blue bricks used as capstones and was told that's the color of the clay. Very hard they are too.

The glossy look on some of your bricks has to do with heat, but also with the makeup of the clay used. The more silica in the mix, the more gloss results.

Cheers,
Jim

[Bacterium]

Re: Brick type decission to be made

Ahhh ok, I've seen remants of old wood fired kilns in one of the local quarriy areas.

Looking at some of the old heritage buildings - not the oldest ones though - I've seen bricks more "glossier" than mine......They look that bright its as though someone has sprayed them with a coat of clear(they haven't though). What does to much silica in the brick result in?..... or can't you have "too much"?

[edschmidt]

Re: Brick type decission to be made

This may, or may not be relevent, but they also produced glazed bricks which had a coating of glaze which at temperature turns into glass. Same as pottery.

[Bacterium]

Re: Brick type decission to be made

ok, yea that would be it as the glaze doesn't run through the brick

[nissanneill]

Re: Brick type decission to be made

Damon,
my mother and grandparents lived on the corner of William St and Grange Road Beverley and I grew up in the area for some years. This area was the most widely used 'brick manufacturing' area in Adelaide, with Hallets located only 1 Km away and at the 'Brickworks Markets'. If you check out the kilns around the basketball stadium (now owned and used by the Woodville Council for their nursery division), on the corner of William St and Toogood St you will see several of the once dozens of kilns that surrounded to old 'pug holes' where the clay was excavated for both brick and terracotta products. (The basketball stadium is actually built in one of these pug holes that was filled with household barbage and some years later was re-excavated and turned into the sporting centree of today). I used to play in several of these huge holes as a young child, but they have all been filled in and built over by industry. The kilns had 4 foot long wood stacked down the side and would fire the kilns once filled and sealed. It would be fired for 3 to 4 days to get to temperature and openned after about a week to 10 days. The bricks that were nearest the heat were extremely hard and glossy and were referred to as Klinka bricks.You could hardly drill them as there were no hammer drills nor tungsten tip bits around then.
The bricks in the centre of the pile or kiln did not get anywhere near the heat and were sold as 'seconds' and used for the building of internal walls. You still see some of these bricks fretting seriously in brick fences and walls today.
The brickmaking industry no longer uses this technology and eack brick is subjected to a much highert and more consistent temperature. Littlehampton claim that their bricks are fired at 1200 deg C and that is why they are hard and shiney.
The Old Red Brick Factory is built over one of the pug holes and the William St frontage was a mass of kilns. (In fact, the beautiful house adjacent to this establishment was the home of the Williams family who made bricks there in the 40's and 50's).
I hope this has helped a fellow local.

Regards.

Neill

[daz]

Re: Brick type decission to be made

glad you found Darley i have been having the same problem, finding firebricks in Victoria. Darley say they have seconds for about 2.50 each is this what you used?

[nissanneill]

Re: Brick type decission to be made

Hi Daz
I looked at the Darley range but with the freight put them a little too expensive. I sourced some second hand bricks that were made in the Dandenongs some years ago called ORDISH with a few others with names as HAF, NGK 26 and one other which is very hard to decipher but looks like Konprite ???ssolox. A real mixture, but I had about 10,000 bricks to choose from but I got 200 good bricks (clean sharp edges with minimal chipping) from only 3 palettes for $1.00 each. The bricks vary in size by up to 6mm but having to cut many to fit properly, I don't anticipate a problem. 90% of the bricks are the same size 'Ordish' brand. I also found around 10 taperred bricks for the arches but will probably use only on the oven entry arch.
They were from a rather large boiler that was dismantled from one of our old abbertoirs.

[Paulygbme]

Re: Brick type decission to be made

Hi Neill, Damon, Everyone,
Gee starting to think us South Aussie people are keen DIYers!!
What a great site - good posts. Great to find such good info after trolling through so much on the net.

Am also going to set out to build the Pompeii style oven - looks good!!

Neill - I have, As i am sure you did, priced Littlehampton firebricks ($5). Just wondering where you picked up your second hand ones at $1 each?? Hopefully there is still enough good ones left from the 10,000??

I too thought of purchasing around 200 to make a 42 inch oven.

Have a nice old rainwater tankstand foundation which i was going to use as my foundation so step one's already done!

Regards
Paul

[nissanneill]

Re: Brick type decission to be made

Hi Paul
welcome to this wonderful informative forum. You will spend many hours sifting through all or some of the information.
I got my grichs from the demolished boiler fo the old abertoir but when I went past it the other week, everything was gone.
Keep your eyes open on ebay and in the saturdays advertiser as they come up occassionally. I have around 80 left over but a friend of the family said that they wanted them for an oven they want me to build down at Tintinara.
I will probably use common solid old reds which I firmly believe are more than adequate, even though many of the posts here recommend the fire bricks.
Read the book from Russel Jeavons, he has built 5 ovens and the 2 in his restaurant at Willunga, are used on a commercial basis 3 night a week for around 4 years and absolutely no troubles. I went down there for my son's birthday, had a damn good look in them, took some pics and sampled his temeratures. Apart from that, you can usually get then for free and just scrape the old mortar off them, cut them in half and use the cheap man's mortar, 1 portland cement, 1 lime, 1 fireclay and 3 brickie sand, to stick it all together. After all, the Italians used very non special mortars in their ovens which have stood for hundreds of years.
I would not get the Littlehampton firebricks as they don't know (or won't tell you their content) but they did tell me that they sell mostly their 4" solid pavers to brick oven builders as they are fired at 1200˚C. Our ovens are only heated to around 500˚C max. I think that their firebricks are for open fireplaces rather than real refractory items.

Neill