kelty-huber on wed 29 nov 00
louis
try putting some fine grog or sand under the platter while bisque fireing.
it may be getting hung up on the shelf while shrinking.
tom
At 05:25 PM 11/30/00 -0500, you wrote:
>I'm hoping that the experienced hands and minds of Clayart can help me
>with this one.
>
>I have been trying for months to make big platters. Not huge, just
>about 16 - 18" in diameter. I have no problem throwing the things.
>My problem comes in the bisque. I can't seem to get one out without
>having a big crack in it, usually from rim to centre. It's usually a
>straight crack through it, stopping at the middle. Sometimes it's a
>"Y" looking crack.
>
>I rarely have problems with s-cracks on anything, and i can do 12"
>dinner plates no problem. In fact, I don't have problems with my 14"
>platters. But once I go bigger than that, forget it. I have been
>paying close attention to the compression when I throw. Maybe I need
>to do it more?
>
>I am using standard #213 porcelaneous stoneware, and bisquing to ^06.
>I put the platters on their own shelf, with nothing on top of them ( I
>thought maybe the weight of other ware might have something to do with
>it, but no). I let the platters dry for weeks before bisquing, and
>they seem to be completely dry when I bisque them.
>
>Thanks in advance. I am most grateful for your help.
>
>...Lois
>
>___________________________________________________________________________
___
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>
Eric Lidicker on thu 30 nov 00
In our experience, cracks in large platters & signs comes from uneven drying
or stresses caused during drying that don't always reveal themselves until
one of the firing processes. You are drying for weeks, but are you getting
them "bone dry" and are they exposed to just below boiling point temps for a
period of time? If not, they may seem dry but there is H2O in there still
which you got by with with your plates but won't on larger pieces. The size
increase you mention may not seem large, but it is exponentionally more
difficult to create platters as you increase the size....so the platters you
are trying to make are much, much harder to make than the plates you have
done in the past and any errors you may make which slide thru on a smaller
piece are magnified.
----- Original Message -----
From: "Jean Cochran"
To:
Sent: Thursday, November 30, 2000 3:59 PM
Subject: Re: All cracked over over cracked platters
>
> Dear Lois,
>
> I've, also, dealt with this problem. One thing that has helped me is to
make
> little round balls out of a kiln wash mixture. I place eight of these
around the
> bottom of the foot with one in the center of the bottom of the platter, so
that it
> is supported equally at all points. This means the platter rests on these
little
> "wads". I believe that the atmosphere can get underneath the platter this
way, and
> that the "wads" help ease the shrinkage stress. Mel will, no doubt, have
some good
> suggestions. He has fed me more ideas to deal with this problem.
>
> Good luck,
>
> Jean Wadsworth Cochran
> Fox Hollow Pottery
> New Haven, Kentucky
>
>
> Lois Ruben Aronow wrote:
>
> > I'm hoping that the experienced hands and minds of Clayart can help me
> > with this one.
> >
> > I have been trying for months to make big platters. Not huge, just
> > about 16 - 18" in diameter. I have no problem throwing the things.
> > My problem comes in the bisque. I can't seem to get one out without
> > having a big crack in it, usually from rim to centre. It's usually a
> > straight crack through it, stopping at the middle. Sometimes it's a
> > "Y" looking crack.
> >
> > I rarely have problems with s-cracks on anything, and i can do 12"
> > dinner plates no problem. In fact, I don't have problems with my 14"
> > platters. But once I go bigger than that, forget it. I have been
> > paying close attention to the compression when I throw. Maybe I need
> > to do it more?
> >
> > I am using standard #213 porcelaneous stoneware, and bisquing to ^06.
> > I put the platters on their own shelf, with nothing on top of them ( I
> > thought maybe the weight of other ware might have something to do with
> > it, but no). I let the platters dry for weeks before bisquing, and
> > they seem to be completely dry when I bisque them.
> >
> > Thanks in advance. I am most grateful for your help.
> >
> > ...Lois
> >
> >
____________________________________________________________________________
__
> > Send postings to clayart@lsv.ceramics.org
> >
> > You may look at the archives for the list or change your subscription
> > settings from http://www.ceramics.org/clayart/
> >
> > Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>
>
____________________________________________________________________________
__
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
Donald G. Goldsobel on thu 30 nov 00
At 05:25 PM 11/30/2000 -0500, you wrote:
>I'm hoping that the experienced hands and minds of Clayart can help me
>with this one.
>
>I have been trying for months to make big platters.
BIG platters can be a big problem if the drying is uneven. I leave mine on
the bat and wrap in plastic for two days, then I tear a small hole in the
center of the plastic and loosely cover it with another piece of plastic.
If it is hot and I am concerned about fast drying, I'll put a towel over
the plastic with the hole in it and then the loose plastic.
Haaandle it as little as possible and lift it with very even support. I
invert it on to another bat to finish the dryin and trimming, but I support
the large flat area with a piece of uphoster's foam alittle thicker than
the depth of the plate.
Try putting some rough sand, like builders sand under it on the shelf when
firing.
Good luck
Donald.
michael wendt on thu 30 nov 00
Hi Lois,
No one gave this idea yet so try this: Get insulating fire brick. You can
cut them up and split them lengthwise with a handsaw if you want different
heights and thicknesses to match your platters. Stack your bottom layer with
taller pots. Put on a shelf layer large enough for your platters. Place the
platters lip down on that shelf layer. Ring the entire perimeter of the
platter shelf layer with the brick. Stack a new tall layer on the next shelf
layer above the platters. This causes them to be heated from both above and
below at the same rate and slows both edge heating and cooling, the main
reason large things crack. I Just finished a pair of 17" sinks. They start
out 20+" in diameter. I fire them upside down in bisque, ringed with brick.
I also make wheel thrown and altered oval platters as large as 24" and this
works for them too. This will also work with large tile forms. Just remember
to alternate taller brick free layers with the brick ringed layers for best
effect. It is very helpful at cone 10 too!
Good Luck,
Michael Wendt wendtpot@lewiston.com
-----Original Message-----
From: Lois Ruben Aronow
To: CLAYART@LSV.CERAMICS.ORG
Date: Thursday, November 30, 2000 4:11 PM
Subject: All cracked over over cracked platters
>I'm hoping that the experienced hands and minds of Clayart can help me
>with this one.
>
>I have been trying for months to make big platters. Not huge, just
>about 16 - 18" in diameter. I have no problem throwing the things.
>My problem comes in the bisque. I can't seem to get one out without
>having a big crack in it, usually from rim to centre. It's usually a
>straight crack through it, stopping at the middle. Sometimes it's a
>"Y" looking crack.
>
>I rarely have problems with s-cracks on anything, and i can do 12"
>dinner plates no problem. In fact, I don't have problems with my 14"
>platters. But once I go bigger than that, forget it. I have been
>paying close attention to the compression when I throw. Maybe I need
>to do it more?
>
>I am using standard #213 porcelaneous stoneware, and bisquing to ^06.
>I put the platters on their own shelf, with nothing on top of them ( I
>thought maybe the weight of other ware might have something to do with
>it, but no). I let the platters dry for weeks before bisquing, and
>they seem to be completely dry when I bisque them.
>
>Thanks in advance. I am most grateful for your help.
>
>...Lois
>
>___________________________________________________________________________
___
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>
vince pitelka on thu 30 nov 00
> try putting some fine grog or sand under the platter while bisque
fireing.
> it may be getting hung up on the shelf while shrinking.
Tom -
While this may work fine on your claybody, I generally advise against it,
because it insulates the bottom of the platter even more. The bed of sand
or grog works well for really large sculptural pieces, but there are better
solutions with big platters. In that case I think that uneven heat rather
than difficulty of movement is the primary culprit. Dannon's suggestion of
thin shims under the platter has always been my favorite solution, in order
to allow air circulation beneath during heating and cooling. And for really
large platters, I just roll out a supply of pencil-thin coils of clay, and
arrange them in a sunburst pattern, and nestle the platter down gently on
top. This supports the platter absolutely evenly, even if it has multiple
foot rings.
And if the platter has a fairly thick rim, do like Dannon mentioned and
simply fire it on edge. As long as you bisque fire no higher than cone 08
they will never warp, and they will heat very evenly.
Best wishes -
- Vince
Vince Pitelka
Home - vpitelka@dekalb.net
615/597-5376
Work - wpitelka@tntech.edu
615/597-6801 ext. 111, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
http://www.craftcenter.tntech.edu/
Lois Ruben Aronow on thu 30 nov 00
I'm hoping that the experienced hands and minds of Clayart can help me
with this one.
I have been trying for months to make big platters. Not huge, just
about 16 - 18" in diameter. I have no problem throwing the things.
My problem comes in the bisque. I can't seem to get one out without
having a big crack in it, usually from rim to centre. It's usually a
straight crack through it, stopping at the middle. Sometimes it's a
"Y" looking crack.
I rarely have problems with s-cracks on anything, and i can do 12"
dinner plates no problem. In fact, I don't have problems with my 14"
platters. But once I go bigger than that, forget it. I have been
paying close attention to the compression when I throw. Maybe I need
to do it more?
I am using standard #213 porcelaneous stoneware, and bisquing to ^06.
I put the platters on their own shelf, with nothing on top of them ( I
thought maybe the weight of other ware might have something to do with
it, but no). I let the platters dry for weeks before bisquing, and
they seem to be completely dry when I bisque them. =20
Thanks in advance. I am most grateful for your help.
....Lois
Linfield College on thu 30 nov 00
on 11/30/00 2:25 PM, Lois Ruben Aronow at gilois@BELLATLANTIC.NET wrote:
>
> I have been trying for months to make big platters..... no problem throwing
the things.... problem comes in the bisque. I can't seem to get one out
without
> having a big crack in it, usually from rim to centre.
> Thanks in advance. I am most grateful for your help.
Lois, the rims of your platters are heating and cooling much faster than
the centers. You can remedy this by putting small shims made of fiber or
soft brick or bisqued or un-bisqued clay. Space the shims evenly around
the platter, leaving plenty of space between shims. This permits the air
and heat to move in/out beneath the platter, and it will heat and cool
more evenly. The heat gets trapped beneath the platter, keeping the
foot and bottom hot while the rim is cooling, or conversely the rim heats
much more rapidly than the bottom, which is protected by the foot-ring and
the shelf.
Another way to fire without these cracks is to fire your platters on edge,
like a tile. Both methods work. You can also notch the foot after
trimming, if it suits your work and your eye to do so. I do this, simply
because I like it, and it has the salutary effect of permitting me to fire
large pieces without cracking in the bisque.
regards
Dannon Rhudy
Cindy Strnad on thu 30 nov 00
Lois,
My cure-all for cracks in big pots: first try adding grog.
Cindy Strnad
Earthen Vessels Pottery
RR 1, Box 51
Custer, SD 57730
USA
earthenv@gwtc.net
http://www.earthenvesselssd.com
June Perry on thu 30 nov 00
Lois, firing too fast can cause the cracking on those large platters. Also,
try putting them on silica sand. It can act as ball bearings, helping the
platter move more easily. Another trick is to use little clay props/wads
under the bottom to raise the plate/platter a bit and permit circulation. T
The cracking can be caused by the rims heating/cooling faster than the flat,
horizontal surface of the base of the platter.
Another trick sometimes used is to make foot on the platter and cut out
holes in a few places along the foot where it meets the bottom of the pot, or
if you prefer, at the bottom of the foot. . You can make that a decorative
aspect of the platter. If you are throwing a sturdy enough rim, particularly
where the rim joins the platter bowl/dish shape, you can try firing them on
their sides in the bisque; but if your rims are too thin and/or too thin
where the rim meets the rest of the platter, you can get a deformed rim.
You may want to check you thickness on the cracked platters and see you have
a fairly even thickness.
Check the archives. This subject has come up before on the list and those
messages should probably be in there.
Regards,
June
Elca Branman on thu 30 nov 00
Wrap the edges in plastic and let the neters dry first.
Elca Branman.. in Sarasota,Florida,USA
elcab1@juno.com
________________________________________________________________
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Jean Cochran on thu 30 nov 00
Dear Lois,
I've, also, dealt with this problem. One thing that has helped me is to make
little round balls out of a kiln wash mixture. I place eight of these around the
bottom of the foot with one in the center of the bottom of the platter, so that it
is supported equally at all points. This means the platter rests on these little
"wads". I believe that the atmosphere can get underneath the platter this way, and
that the "wads" help ease the shrinkage stress. Mel will, no doubt, have some good
suggestions. He has fed me more ideas to deal with this problem.
Good luck,
Jean Wadsworth Cochran
Fox Hollow Pottery
New Haven, Kentucky
Lois Ruben Aronow wrote:
> I'm hoping that the experienced hands and minds of Clayart can help me
> with this one.
>
> I have been trying for months to make big platters. Not huge, just
> about 16 - 18" in diameter. I have no problem throwing the things.
> My problem comes in the bisque. I can't seem to get one out without
> having a big crack in it, usually from rim to centre. It's usually a
> straight crack through it, stopping at the middle. Sometimes it's a
> "Y" looking crack.
>
> I rarely have problems with s-cracks on anything, and i can do 12"
> dinner plates no problem. In fact, I don't have problems with my 14"
> platters. But once I go bigger than that, forget it. I have been
> paying close attention to the compression when I throw. Maybe I need
> to do it more?
>
> I am using standard #213 porcelaneous stoneware, and bisquing to ^06.
> I put the platters on their own shelf, with nothing on top of them ( I
> thought maybe the weight of other ware might have something to do with
> it, but no). I let the platters dry for weeks before bisquing, and
> they seem to be completely dry when I bisque them.
>
> Thanks in advance. I am most grateful for your help.
>
> ...Lois
>
> ______________________________________________________________________________
> Send postings to clayart@lsv.ceramics.org
>
> You may look at the archives for the list or change your subscription
> settings from http://www.ceramics.org/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
Earl Brunner on thu 30 nov 00
I have also noticed that I have trouble getting large wide things
through the electric kiln at the art center intact.
I haven't noticed it as much in my gas kiln, but lately the electric has
been killing them.
If the foot has to span over two shelves it can cause problems, even if
the shelves look level.
I move them to the middle of the kiln as much as possible, with things
around the edges to act as heat sinks to hold heat in.
Linfield College wrote:
> on 11/30/00 2:25 PM, Lois Ruben Aronow at gilois@BELLATLANTIC.NET wrote:
>
>
>> I have been trying for months to make big platters..... no problem throwing
>
> the things.... problem comes in the bisque. I can't seem to get one out
> without
>
>> having a big crack in it, usually from rim to centre.
>> Thanks in advance. I am most grateful for your help.
>
>
>
> Lois, the rims of your platters are heating and cooling much faster than
> the centers. You can remedy this by putting small shims made of fiber or
> soft brick or bisqued or un-bisqued clay. Space the shims evenly around
> the platter, leaving plenty of space between shims. This permits the air
> and heat to move in/out beneath the platter, and it will heat and cool
> more evenly. The heat gets trapped beneath the platter, keeping the
> foot and bottom hot while the rim is cooling, or conversely the rim heats
> much more rapidly than the bottom, which is protected by the foot-ring and
> the shelf.
>
>
--
Earl Brunner
http://coyote.accessnv.com/bruec
mailto:bruec@anv.net
Sue Warrington on fri 1 dec 00
My experience is that it is probably a firing problem rather than a making
problem.
What sort of kiln do you use? Some of the single brick kilns like Skutt are
diffiicult for large platters
Usually it is casued by uneven heating.
Suggestions
Put large plates at the middle to top of the kiln NEVER AT THE BOTTOM
Leave at least 2 - 4 inches above the plate before setting next shelf
Surround the edges of the plates with kin fillers or props to even the heat
if they are near the elements - also helps to stop sudden cooling
Fire the first 450 celsius slowly 60 degrees per hour
Fire down if you think it is cooling too quick.
Other hints could be to put a small layer of zircon silicate or such to help
it shrink and move on the kiln shelf
Good luck
Sue Warrington
JODO96@AOL.COM on fri 1 dec 00
Lois
We had this problem several years ago. Not only did we have cracks in our
platters but it many other items. We lost 75% of our ware due to cracks. So
you can imagine what we were thinking. First we examined our technique.
How thick we were throwing.
Flat bottoms vs footed and double footed
How much pressure we were applying to the bottoms as well as the rims in
trimming.
Using a support in the center of the platter when trimming or not.
Slab work vs thrown.
Rate of drying, as well as how we dried, using plastic and the location of
drying the ware whether it was too close to the heat source, example top
shelf vs bottom/middle..
Drying upside down vs right side up.
How we bis, rate /temp.
For us it did offer an opportunity to improve on our procedure. But it was
not our technique,
Finally call your supplier and ask if there have been any changes to your
clay body. Or call the manufacturer. For us we were using standard 245 and
they changed the ball clay, which was ultimately the problem. This lead to a
lot of testing again for a new clay body.
Hope this is helpful
Dorothy Weber
JoDo Pottery
Manakin-Sabot, Va.
Billie Neal on fri 1 dec 00
and lets not forget about firing standing on edge either.....i have had nary
a platter crack since changing to this method in bisque. mel gave a very
good description of "how to" several months back
billie
Joseph Herbert on sat 2 dec 00
Leaving aside steam explosions, pots crack for one of two reasons: Impact or
differential expansion/contraction. Unfortunately, there are many times and
circumstances in the life of a pot that can allow these things to happen.
Drying, heating, and cooling easily lead to parts of a pot expanding or
contracting faster than the rest of it. Some treatments on pottery faults
will try to identify the source of the crack from its form. These can be
helpful. Mostly what you have to do, after you see all the advice of “Do
this,” “Don’t do this” is to devise ways of working that avoid the stresses
(or impacts) that cause cracks.
I once had a greenware lady bisque fire some of my thrown pots. Several
showed dunting cracks across the foot ring. She never had any trouble with
cracking in her firings she did for herself. I eventually figured out that
her slip cast pieces were all one thickness - totally uniform. For those
pieces, the rate of heating and cooling wasn’t much of an issue after the
requirements to avoid cracking during quartz inversions. For my pieces,
where the foot ring contained a considerable portion of the mass of the pot,
it was. If the foot ring stayed hot (and large) while the rim of the pot
cooled (and got smaller), considerable stresses built up and there were
cracks. Pieces that were more uniform, smaller bowls with small foot rings,
had no problems.
Anyway, it is easy to state and difficult to diagnose. Try to keep in mind
the expansion and contraction that takes place during heating and the
contraction during drying. Tailor your methods to reduce the suddenness of
changes and things should get better.
Joseph Herbert
Ron Roy on sun 3 dec 00
Hi Lois,
I have been watching the answers to this and I'm surprised at how much
misunderstanding there is on this subject.
There are two possible kinds of cracks - if the cracks are "open" (not
closed) then they are work or drying related and are either there or
potentially there before the firing started.
The second kind are closed (not open) and are due to uneven cooling through
the quartz inversion at 573C. Rim goes through the quartz inversion before
the rest of the plate - tries to get smaller - can't because the other
quartz in the foot and walls is not cool enough to go through the
inversion. Rim has to crack. It's called bisque dunting.
Craig has one of the solutions - bisque higher to make the ware stronger.
Shimming the foot up off the shelf helps to cool the plate more evenly,
keep the ware at the top of the kiln where it cools slower and more evenly.
Stacking the plates rim to rim helps delay the rims cooling - not my
favorite because it can lead to other problems. Keeping the rims heavier
and trimming the foot and body more to have a more even cross section will
help. Firing down through the quartz inversion will do it. Make sure there
are no drafts (vent systems off and/or dampers closed and all ports and spy
holes closed.
This problem is directly related to how much free quartz is in the body -
porcelain usually has about 25% free quartz so the problem is even more
serious in that case.
Any way you can slow the cooling of the rims will help.
If you could see the crack when it first happens it will be open - as the
rest of the pot goes through the inversion the crack closes up.
RR
>I'm hoping that the experienced hands and minds of Clayart can help me
>with this one.
>
>I have been trying for months to make big platters. Not huge, just
>about 16 - 18" in diameter. I have no problem throwing the things.
>My problem comes in the bisque. I can't seem to get one out without
>having a big crack in it, usually from rim to centre. It's usually a
>straight crack through it, stopping at the middle. Sometimes it's a
>"Y" looking crack.
>
>I rarely have problems with s-cracks on anything, and i can do 12"
>dinner plates no problem. In fact, I don't have problems with my 14"
>platters. But once I go bigger than that, forget it. I have been
>paying close attention to the compression when I throw. Maybe I need
>to do it more?
>
>I am using standard #213 porcelaneous stoneware, and bisquing to ^06.
>I put the platters on their own shelf, with nothing on top of them ( I
>thought maybe the weight of other ware might have something to do with
>it, but no). I let the platters dry for weeks before bisquing, and
>they seem to be completely dry when I bisque them.
>
>Thanks in advance. I am most grateful for your help.
>
>...Lois
Ron Roy
93 Pegasus Trail
Scarborough
Ontario, Canada
M1G 3N8
Evenings 416-439-2621
Fax 416-438-7849
kelty-huber on sun 3 dec 00
Thanks Roy
as usual, a precise answer that increases our understanding.
Tom Huber
At 01:36 AM 12/3/00 -0500, you wrote:
>Hi Lois,
>
>I have been watching the answers to this and I'm surprised at how much
>misunderstanding there is on this subject.
>
>There are two possible kinds of cracks - if the cracks are "open" (not
>closed) then they are work or drying related and are either there or
>potentially there before the firing started.
>The second kind are closed (not open) and are due to uneven cooling through
>the quartz inversion at 573C. Rim goes through the quartz inversion before
>the rest of the plate - tries to get smaller - can't because the other
>quartz in the foot and walls is not cool enough to go through the
>inversion. Rim has to crack. It's called bisque dunting.
>
>Craig has one of the solutions - bisque higher to make the ware stronger.
>Shimming the foot up off the shelf helps to cool the plate more evenly,
>keep the ware at the top of the kiln where it cools slower and more evenly.
>Stacking the plates rim to rim helps delay the rims cooling - not my
>favorite because it can lead to other problems. Keeping the rims heavier
>and trimming the foot and body more to have a more even cross section will
>help. Firing down through the quartz inversion will do it. Make sure there
>are no drafts (vent systems off and/or dampers closed and all ports and spy
>holes closed.
>
>This problem is directly related to how much free quartz is in the body -
>porcelain usually has about 25% free quartz so the problem is even more
>serious in that case.
>
>Any way you can slow the cooling of the rims will help.
>
>If you could see the crack when it first happens it will be open - as the
>rest of the pot goes through the inversion the crack closes up.
>
>RR
>
>
>
>
>Ron Roy
>93 Pegasus Trail
>Scarborough
>Ontario, Canada
>M1G 3N8
>Evenings 416-439-2621
>Fax 416-438-7849
>
>___________________________________________________________________________
___
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at
melpots@pclink.com.
>
Bob Hamm on mon 4 dec 00
> And if the platter has a fairly thick rim, do like Dannon mentioned and
> simply fire it on edge. As long as you bisque fire no higher than cone 08
> they will never warp, and they will heat very evenly.
> Best wishes -
> - Vince
>
To say that plates will never warp may be a wee bit overstated Vince.
I used to fire all my plates, up to 20 inches green, on there edge when I
was working with a cone 8 clay. Bisgued to cone 010 in an electric kiln and
never had any cracked or warped plates.
Then I switched to cone 6 and still bisqued to cone 010. The first time
bisqued plates, I loaded up a whole kiln load of plates, must have been 50
to 60 pieces, dinner plates to 15 inch platters. A cone 010 bisgue and all
the plates had a flat spot on the bottom edge. I do believe this method will
work for high temperature bodies ,but I would test the lower temperature
bodies before I loaded a big batch.
As to firing large plates. I fire plates up to 22 1/2 inches wide, often
very flat. I load them on a dry shelf, no shims, and in the case of the
largest the rims are touching the brick on opposite edges. I have never had
any problems, cross my fingers, knock on wood. I don't know why it works for
me, but happy it does. I do fire my kilns slower then anyone I know.
Bob Hamm, getting ready for my last sale this year while trying to complete
my last wholesale and retail orders. As the days go by the mind and body are
becoming increasingly tired and sluggish. Two more weeks. Sigh.
I can hardly wait.
Bob Hamm
Super Mud Works
Kelowna, B.C. Canada
Phone 250 765-8876
Email bobhamm@look.ca
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