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making bricks

updated wed 28 apr 10

 

mel jacobson on mon 5 aug 02


i would like to hear more from
those that have made brick. ifb's in
fact.

it peaks my interest, and i would
like some clear information...tested information,
not hear-say.

i have thought before that i would like
to make some door bricks...special sizes. just
sounds interesting. like, something i have
never done in clay.

mel
From:
Minnetonka, Minnesota, U.S.A.
web site: http://www.pclink.com/melpots

Ann Brink on mon 5 aug 02


Hi Mel- I made 6 large bricks for the door of the gas kiln years ago, using
a variation of one of Lowell Baker's refractory material recipies. I
remember it had 1 part Lumnite refractory cement, 1 part fireclay and 3
parts vermiculite in it by volume. There is a photo of my bricked up kiln at
this URL: http://www.impulse.net/~billann/gasfiring.html

They are fairly lightweight. They did shrink, so I stuff some fibre in
between the bricks.
I made them on the driveway, setting up some 1x6es crosswise (with slits).
The sides, back and top of the kiln are the same stuff. As it all shrank,
and developed cracks, last year I lined the top with fibre to stop the
crumbs. I only fire it a few times each year- mostly I use the Skutt.

Regards,
Ann Brink in CA

Mel wrote:
> i would like to hear more from
> those that have made brick. ifb's in
> fact.
>
> it peaks my interest, and i would
> like some clear information...tested information,
> not hear-say.
>
> i have thought before that i would like
> to make some door bricks...special sizes. just
> sounds interesting. like, something i have
> never done in clay.
>
> mel
> From:
> Minnetonka, Minnesota, U.S.A.
> web site: http://www.pclink.com/melpots
>
>

Hank Murrow on mon 5 aug 02


> i would like to hear more from
>those that have made brick. ifb's in
>fact.

Dear Mel;

While at U of Oregon, Bruce Finch, now of Roseburg, OR, made
some sponge with slip and yoghurt. The yoghurt fermented creating
bubbles in the slip which was poured into molds. Very smelly
operation done in garbage cans. Bricks fired and used in kilns there.
I can't offer you figures, but will try to reach Finch for his
recollection.

Cheers, Hank in Eugene

Michael Wendt on wed 7 aug 02


Mel and all,
I have made a lot of insulating firebricks and very large scale ones too !
Some were 24" X 12" X 2.5" . Is it practical for the everyday potter? No.
I mine the clay 30 miles north of Lewiston, Idaho at Helmer. Result= low
clay cost.
I get the sawdust at Juliaetta from a saw mill for nearly nothing and they
produce semi loads every month. Result= low burnout cost.
Mixing is done in a large clay mixer, not by hand. Again, a low cost in
time.
Forming is done in a metal mold with hydraulic ram. Very fast!
Firing must be a couple cones higher than you plan to use the brick, so a
gas kiln is a must. Mine is rated to 2600 degrees F.

Most people don't have this equipment and it is far cheaper to buy bricks
than to buy all this equipment.
Why am I? I plan to make very large scale monolithic brick for sale to
potters who want the special properties the hybrid "C" form gives, fast
heating, slow cooling and light weight.
This all started because I wanted a special shape for the calciner I built.
Now we are almost ready to begin production of Helmer calcine in the flash
calciner.

Sponge is the reverse of what you want for a burnout matrix. You wind up
with loosely bonded spheres. The best and strongest bricks would have
spherical voids of modest size to reduce stress concentrations. The webs
would then be thick and strong.
Sawdust has sharp edges and so is not the best medium for burn out, but it
is very cheap.
Durability can be very good, though. The bricks I made a year ago have fired
over 100 times now and still look new and uncracked.

Try this: mix 0.8 lbs of Kaolin with 2 cups of water , 2 cups of paper
fiber and 1/4 cup of Palmolive detergent. Stir vigorously and add a little
water at a time until you get about 1 gallon of foam. Pour this out in a
thin sheet on newspaper and let dry. Fire. Add another layer of the foam and
fire. Build up layers of foam until you get the desired thickness. Then hard
fire one last time and cut into shapes needed. That is how we make Helfoam
for flame retention flanges and deflectors. Easy, too.
Regards,
Michael Wendt wendtpot@lewiston.com
Wendt Pottery
2729 Clearwater Avenue
Lewiston, Idaho 83501
1-208-746-3724
wendtpottery.com

John Goode on sat 24 apr 10


Hi Frank and all
I live near Elgin Texas where there are three brick factories.I have toure=
d
the facility at Acme brick and this is how they do it with a few more steps
for some clays as they run up to 40 mixes. Most of the clays come from the
ground to kiln with NO additives, others just a few. There are four to five
clays in this region with in 5- 10 miles that are all unique.If anyone ever
comes here there are free tours with advance notice.One of the factories
makes 1x1 tile and fire bricks you can purchase there.It is amazing to see
the amount of clay burning at once.This community east of Austin 22 miles
has hundreds of clay workers from the factories strip mines of ALCOA to
potters to tile makers etc. The mayor of Elgin is a tilemaker and has an
excellent line of tile.If anyone has any questions about this area please
let me know and maybe I can offer some insight.
John Goode
watermarktile.com

On Sat, Apr 24, 2010 at 7:46 PM, Frank Gaydos wrot=
e:

> Taking a break from final firings for the semester. Doing six kilns a day
> for the last four days, another four days ahead for sure, maybe more. A
> mixture of bisque, soakings and glaze firings. Under the gun to get it do=
ne.
>
>
>
> Watched one of the how they do it shows and it featured brick making:
>
>
>
> Crush equal parts of clay and shale into a fine powder. Add a smidgen of
> Barium.
>
> Add just enough water to clump the dry mix.
>
> Extrude the clay into 11 foot long slugs with three holes built into it.
>
> Push the slug through a wire mesh making 50 bricks.
>
> Load 10,000 bricks into a car kiln and soak for 2 days in 250F heat.
>
> Fire to 2000F with natural gas.
>
> Bricks emerge weighing one pound less.
>
>
>
> Pretty amazing.
>
> Frank Gaydos
>
>

Snail Scott on sun 25 apr 10


On Apr 24, 2010, at 7:46 PM, Frank Gaydos wrote:
> Watched one of the how they do it shows and it featured brick making:



Nearly the last local brick factory is still operating just
down the road from me, and I begged a tour one day.
It was much as you describe.

They have two huge piles out back: one of local clay,
and one of local shale. Weeds growing on them, etc;
not clean or processed in any way. A front-end loader
dumps a scoop of each into the hopper of the mixer,
which dumps straight into the extruder. This is a smaller
operation than you may have seen on TV, so the extruder
just does a one-brick-around sized pug, about 10 bricks
long. That gets sprinkled with colorants and run between
texturing rollers which get swapped depending on how
'rustic' the desired effect is to be, then a mandolin-type
cutter drops and cuts the bricks apart.

(This explained a long-pondered mystery for me. When I
would sit in the drive-through lane at the fast-food places,
I'd get a long look at the bricks of the building, and notice
that the textures repeated on the bricks - one distinctive
divot might appear on, say, one in every half-dozen bricks,
but not in exactly the same position on each brick. Now I
know why!)

The separated bricks would run on their conveyor belt
to the kiln car, where they were stacked on the car until
it was full and the next car was rolled into place. (The
manager told be that they had tried to automate the car
loading, but it proved difficult to get any new machine to
synch up with the pace of the existing machines, or vice-
versa, so they went back to human manual labor.) The kiln
cars roll into one end of the tunnel kiln and out the other
as finished fired bricks (17 hours, I recall.) The brick clay
is very, very stiff coming out of the extruder, already stiff
leather-hard. It goes in to the kiln within about ten minutes
of extrusion; more like one minute if it's the last load onto
the car.

At the other end, the kiln cars are unloaded by humans,
and a gang of six guys stands around of a sort of steel
carousel which holds wooden frames. The first guy
stacks the bottom row of bricks into the frame, which
turns and the second guy loads the second row of
bricks onto it, then on the third guy and so on until the
frame is full, then a big piston shoves all the bricks out
of the frame onto a pallet, and when the pallet is full it
gets strapped and taken out to the yard. I was amazed
to see so much human labor still involved, but it's just
not a large enough operation to make machines more
cost-effective. The loaders basically get paid by the job
rather than by the hour, so they work amazingly fast
so they can go home sooner. As soon as they load
(I think it was) 10,000 bricks they are off-shift, usually
by 2 pm.

I went there hoping I'd be able to buy unfired brick to
carve. It turns out that the design of their production line
is such that you really can't get at the bricks at that stage,
as it's all on a high conveyor belt with only a catwalk
alongside until it reaches the kiln car. Not worth it for
them to disrupt the whole loading operation unless I
was gonna buy a whole lot more than I wanted to. Still,
nice to know there's still a small-scale operation in the
area for the future.

-Snail

Frank Gaydos on sun 25 apr 10


Taking a break from final firings for the semester. Doing six kilns a day f=
=3D
or the last four days, another four days ahead for sure, maybe more. A mixt=
=3D
ure of bisque, soakings and glaze firings. Under the gun to get it done.=3D=
20



Watched one of the how they do it shows and it featured brick making:=3D20



Crush equal parts of clay and shale into a fine powder. Add a smidgen of Ba=
=3D
rium.=3D20

Add just enough water to clump the dry mix.=3D20

Extrude the clay into 11 foot long slugs with three holes built into it.=3D=
20

Push the slug through a wire mesh making 50 bricks.=3D20

Load 10,000 bricks into a car kiln and soak for 2 days in 250F heat.=3D20

Fire to 2000F with natural gas.=3D20

Bricks emerge weighing one pound less.=3D20



Pretty amazing.=3D20

Frank Gaydos=3D20
=3DC2=3DA0

jonathan byler on mon 26 apr 10


how do they stack these bricks in the kiln? is there a bunch of
airspace between them or are they tightly packed? the one time I
tried to fire a load of bricks in one of our gas kilns - needless to
say, it wasn't pretty.

Snail Scott on mon 26 apr 10


On Apr 26, 2010, at 2:12 PM, jonathan byler wrote:

> how do they stack these bricks in the kiln? is there a bunch of
> airspace between them or are they tightly packed?


Sort of a basketweave stack, one layer front-to-
back, and the next side-to-side, nothing tight together:
maybe a 1/2" between bricks, and the holes in the
bricks go crosswise. I think they rely a lot on air
movement (convection) within the kiln, and not much
on radiant heat, but this is just my conjecture.

-Snail

Tim Frederich on tue 27 apr 10


Hi all,
I call on about 25 brick plants in my sales territory. Most plants today us=
e
setting machines to automatically place the brick on the kiln cars. The
brick are placed very close together and the rows are alternated. Depending
on the size of the tunnel kiln and the kiln car, there can be up to
10,000-12,000 brick on a car. I call on one plant that produces 185 million
brick a year. Needless to say, their business is not very good at this time=
.
The kiln cars are run through dryers that use waste heat from the tunnel
kiln and can be in the dryer for up to 24 hours before entering the tunnel
kiln. The kiln has a preheat zone, a hot zone, and a cool down zone. It
might take up to 40 hours for a car to pushed through the kiln. Most of the
large tunnel kilns are fired with natural gas but they also use methane,
petcoke (a mixture of petroleum and coal) or sawdust. These kilns are eithe=
r
side or top fired and can have up to 100 burners on the kiln placed on both
sides. Most have forced air and the firing atmosphere can be very turbulent
in the hot zone. The slow push rate allows the heat to penetrate most of th=
e
brick. There is always a percentage of loss in the process and a lot of
plants grind this material up and use it as grog in the next batch of
material.

Tim Frederich
Dublin, Ohio

On Mon, Apr 26, 2010 at 7:32 PM, Snail Scott wro=
te:

> On Apr 26, 2010, at 2:12 PM, jonathan byler wrote:
>
> how do they stack these bricks in the kiln? is there a bunch of
>> airspace between them or are they tightly packed?
>>
>
>
> Sort of a basketweave stack, one layer front-to-
> back, and the next side-to-side, nothing tight together:
> maybe a 1/2" between bricks, and the holes in the
> bricks go crosswise. I think they rely a lot on air
> movement (convection) within the kiln, and not much
> on radiant heat, but this is just my conjecture.
>
> -Snail
>



--
Tim Frederich; Diversified Ceramic Services Inc.; 7144 Scioto Road, Dublin,
Ohio 43017; phone: 614-946-2156; fax: 614-873-6614; e-mail:
tfrederich@gmail.com