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fire bricks

updated fri 3 mar 06

 

John Baisch on sat 17 aug 96


Hello all,

I'm in the process of re-vamping my Raku Kiln and
have run out of fire bricks. I checked with the local supplier
and I can't find any low cost 2200F bricks.

If anyone has some used fire bricks they would like to
get rid of, I would be more than happy to negoiate
a reasonable price + shipping costs.

I only need 30 - 50 fire bricks....

Thanks,

JB
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~ John Baisch ~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~ E-Mail: jbaisch@micron.net ~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Carl Ross on sat 17 aug 96

JB,

We are having our heating redone in our bakery where i'll be setting up shop,
I'm not sure of the quality, but the brick around our old boiler is
refractory however i'm unsure of the temp. rating. the building is 102 years
old and this is the original furnace (it used to burn coal, then oil and
until now, natural gas). The brick seems newer then the furnace though, it
looks almost like it was some state code requirement since it could work just
fine without it. Anyway, if you can tell me how to tell, I'll gladly look
into shipping for some negotiable offer.

hope to hear from you,


Carl in Phillips

Tim Knick on thu 23 feb 06


I am planning on building a woodfire kiln that will go to cone 13. Brick
cost is too expensive. So, I was tinkering with homade (inexpensive)
castable recipes. What if i were to mix 50 percent aluminum hydrate, 25
percent whiting, and 25 percent coal powder? I could make a big brick
form, let them dry and then fire them too cone 10 in my electric. My
thought process was this: Because of the coal the brick would get hotter
in the electric at cone 10 than it would ever get again (even in a cone 13
woodfiring). Also, where the coal burned out would be those insulating air
pockets. Is this a bad idea?
Thanks for your response,
Tim

Hank Murrow on thu 23 feb 06


On Feb 23, 2006, at 2:45 PM, Tim Knick wrote:

> I am planning on building a woodfire kiln that will go to cone 13.
> Brick
> cost is too expensive. So, I was tinkering with homade (inexpensive)
> castable recipes. What if i were to mix 50 percent aluminum hydrate,
> 25
> percent whiting, and 25 percent coal powder? I could make a big brick
> form, let them dry and then fire them too cone 10 in my electric. My
> thought process was this: Because of the coal the brick would get
> hotter
> in the electric at cone 10 than it would ever get again (even in a
> cone 13
> woodfiring). Also, where the coal burned out would be those insulating
> air
> pockets. Is this a bad idea?

dear Tim;

Have you thought of what effect the reduction of the coal when burning
would do to your elements? And what about a firing that went beyond
Cone 10, or whatever your eloectric is rated for?

Thinking twice, Hank in Eugene
www.murrow.biz/hank

Vince Pitelka on thu 23 feb 06


Tim -
You need to do some serious research into refractories. The object you
refer to would not be a brick. After firing it would be a pile of powdered
alumina and whiting, with nothing to hold it together. The coal dust would
not make the brick fire any hotter than the temperature of the kiln. Also,
a brick that you make with 50% alumina would likely be more expensive than
high-duty commercially made firebrick. You can find good sources of used
brick if you do some research. It takes a tremendous amount of planning and
hard work to build a wood kiln. Why make it form some sort of haphazard
homemade refractory that could fail soon? Save your pennies and buy brick.
Good luck -
- Vince

Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/

Tim wrote:
>I am planning on building a woodfire kiln that will go to cone 13. Brick
> cost is too expensive. So, I was tinkering with homade (inexpensive)
> castable recipes. What if i were to mix 50 percent aluminum hydrate, 25
> percent whiting, and 25 percent coal powder? I could make a big brick
> form, let them dry and then fire them too cone 10 in my electric. My
> thought process was this: Because of the coal the brick would get hotter
> in the electric at cone 10 than it would ever get again (even in a cone 13
> woodfiring). Also, where the coal burned out would be those insulating air
> pockets. Is this a bad idea?

Michael Wendt on thu 23 feb 06


Tim,
Use kaolin, not whiting. Use fine saw dust if you wish. do trials until you
find the correct density although the usual thought is to use high density
hard brick as a liner for wood fired kilns.
Regards,
Michael Wendt
Wendt Pottery
2729 Clearwater Ave
Lewiston, Idaho 83501
USA
wendtpot@lewiston.com
www.wendtpottery.com

Paul Herman on thu 23 feb 06


Tim,

You wrote:
> I am planning on building a woodfire kiln that will go to cone 13.
> Brick
> cost is too expensive. So, I was tinkering with homade (inexpensive)
> castable recipes. What if i were to mix 50 percent aluminum
> hydrate, 25
> percent whiting, and 25 percent coal powder?

Well Grasshopper, it sounds like you need some more experience around
cone 13 wood fired kilns. Is there a competent wood firer nearby who
might let you attend a firing or two? I live in California and you
can visit April 11 or 12 when we're firing. Successful wood fired
kilns I've seen are hard firebrick inside and insulation outside.

Yes bricks are expensive, but they are way cheaper than alumina
hydrate. And whiting is a flux, you don't need that!

Get some good books on woodfire. Jack Troy, and Minogue & Sanderson
are authors I like. Get Michael Cardew's "Pioneer Pottery" and read
the sections on refractories and brick making, and that will give you
a foundation to plan from. Brick making is painful too, like spending
dough on bricks.

Consider scrounging for the brick. Many industries throw away vast
piles of that stuff as they modernize or go belly up. Look for a
dying industry that uses a heat treatment process of some kind. My
brick came from a sawmill modernization. A lifetime supply (four semi-
truck loads) for virtual peanuts.

Good luck on the woodfire adventure, it ain't easy!

Best,

Paul Herman

Great Basin Pottery
Doyle, California US
http://greatbasinpottery.com

tim knick on mon 27 feb 06


Another question about firebricks.
What if I were to take grog (composed of crushed firebrick $460 for
2000lb) and mix it with refractory cement (calcium aluminate not portland).
Has anyone tried this?

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tim knick on tue 28 feb 06


to Everyone who responded to my firebrick question-
I found calcium aluminate cement that i can mix with crushed firebrick. In
essence, this would be refractory concrete. The cement (lafarge "secar 71")
has a cone rating of somewheres around 30. Crushed firebrick would have
varied cone ratings, as each little peice may have come from a different
brick with a different rating, but regardless i think it would work fine. i
could stretch it with kyanite (powedered) as regular concrete is generally
stretched with sand. crushed brick and kyanite are very inexpensive, both
around 450$ a ton. the cement is going to be the costly part, how far i can
stretch it will be a factor (without crumbling blocks). lafarge is going to
call me in the next day or two with a price including shipping from VA.
After that i have to wait for the 100lb bag to arrive and experiment with
ratios, and crush weight and such.
i can get mid. duty (2600) firebrick, 9 by 4.5 by 2.5 for 1.35$ a piece.
Maybe i will be able to make a 12 by 12 by 6 block for the same price. i
don't know. i will post my findings to the list after the bag arrives.
Take a look at some of the products lafarge makes if you like
http://www.lcainc.com/product.html#cements
thankyou for responding (my kiln would thank you too if it could talk,
coal=bad idea)
Tim

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Ivor and Olive Lewis on tue 28 feb 06


Dear Tim knick,

You ask ..."What if I were to take grog (composed of crushed firebrick =
$460 for
2000lb) and mix it with refractory cement (calcium aluminate not =
portland).
Has anyone tried this?"...

You do not give the cost of Calcium Aluminate. As I recall from 1965 =
that stuff in not small bickies

Yes it will work but it will be costly. Remember, you will need brick =
moulds which you will have to make.

Much better to go scavenging. My first kiln was made from "Seconds", =
slightly sub standard because they were not of the correct thickness. =
Manager at the Brickworks was really helpful. Only wanted two bob a =
hundred. The arch was cast from the mixture you describe. Stack was 8 =
inch sewer pipes.Think I had four to give me a twelve foot draw. =
Bellowed like a church organ at full draught.

Some domestic bricks are made from almost pure Kaolin. They are =
refractory. By the palette they are reasonable in price. Pays to ask =
around ! !

Reckon you will have to get in and get your hands dirty and you nails =
chipped.

Regards.

Ivor Lewis.
Redhill,
South Australia.

John Britt on wed 1 mar 06


Tim,

Call Jim Wunch at Larkin and see what he says. He may be able to get you a
better deal on ready made castable. Or have some advise for you. Thirty
years (or more) in the brick industry might save you some headaches and
money.

Best of luck,

John Britt
www.johnbrittpottery.com