Carolyn Sawyer on fri 25 jun 99
Hi everybody,
When I take my pieces out of the kiln (at room temp) they ping. Should I be
worried? Is there something I'm doing wrong? They aren't crackling or
crazing but I just think it shouldn't be doing this.
Also, if you were making a glaze that called for just Rutile and you had
light and dark on hand, which would you use? I fire ^6 ox.
Thanks
Carolyn
Campobello SC
Jeri Palmer on sun 27 jun 99
The pinging you hear is your pots singing to you. This is one of my favorite
parts of firing. Actually it is the sound of your pieces cooling. I can sit
for hours and just enjoy this sensual feast of the colors, forms, textures
and to have the music of the pots too is almost more beauty than I can bear.
Enjoy. Jeri
Jeri Palmer on sun 27 jun 99
The pinging you hear is your pots singing to you. This is one of my favorite
parts of firing. Actually it is the sound of your pieces cooling. I can sit
for hours and just enjoy this sensual feast of the colors, forms, textures
and to have the music of the pots too is almost more beauty than I can bear.
Enjoy. Jeri
Mike Gordon on sun 27 jun 99
Hi,
I, too have been experimenting with commercial glaze, a clear, brushed
over B-Mix from laguna and fired at cone 06 oxidation. They ping for 2
or 3 weeks. I rub ink into the cracks. Sometimes I re-heat to maybe 150
degrees and spray with water to increase the cracking. When I ink as
soon as possible the cracks seem to be larger. They get smaller the
longer it pings.Experimenting is the fun part! Mike
Mike Gordon on sun 27 jun 99
Hi,
I, too have been experimenting with commercial glaze, a clear, brushed
over B-Mix from laguna and fired at cone 06 oxidation. They ping for 2
or 3 weeks. I rub ink into the cracks. Sometimes I re-heat to maybe 150
degrees and spray with water to increase the cracking. When I ink as
soon as possible the cracks seem to be larger. They get smaller the
longer it pings.Experimenting is the fun part! Mike
elizabet on mon 28 jun 99
>>The pinging you hear is your pots singing to you. This is one of my favorite
parts of firing. Actually it is the sound of your pieces cooling. I can sit
for hours and just enjoy this sensual feast of the colors, forms, textures
and to have the music of the pots too is almost more beauty than I can bear.
Enjoy. Jeri<<
This post reminded me....recently I fired my first load of crackled pots. I had
only before tested the crackle glaze on little tiles, so the pinging was minim
Nothing that I had read prepared me for the experience of the cooling of my
first real load. For more than an hour, it sounded like miniature wind chimes
as they pinged randomly in different pitches, over and over. It was
magical!!!! I decided the reason that I never read anything about it was........
it's a potters' secret so as not to ruin the surprise!!!!! A concert by the
teeney tiny Ping Pixies. ;-)
Elizabeth, who can't wait for her next little concert.
Gary & Carla Goldberg on mon 28 jun 99
> >>When I take my pieces out of the kiln (at room temp) they ping. Should I be
I had some pieces that did the same thing. I could hear them pinging 2
weeks after taking them out of the kiln. I took the pieces to a local
pottery store and they said the glaze is not compatible with the clay.
They suggested I put the commercial glaze on while the clay is leather
hard and then fire it. Before that, I was firing the piece and then
putting glaze on it, and firing it again. I followed their suggestion
and it worked, but I didn't have as much control of the glazes that I
like when applying to bisque.
Phyllis Gibson on wed 30 jun 99
In a message dated 6/28/99 8:25:30 AM Central Daylight Time,
elizabet@cecomet.net writes:
<< CLAYART@LSV.UKY.EDU
I am just so upset after all these years not to have heard the "ping
pixies"...and from a full load too!
Do you hear this after using crackle glazes? I don't use very much crackle
glazes but if I have to do a full kiln load to enjoy this experience, then I
want to plan to do so.
If crackle is used and is fired to 06...it won't hold water will it?....so,
would one use another type glaze for the interior of their ware?
Thank you,
Phyllis Gibson
Alabama's still raining
----------------------------Original message----------------------------
>>The pinging you hear is your pots singing to you. This is one of my
favorite
parts of firing. Actually it is the sound of your pieces cooling. I can sit
for hours and just enjoy this sensual feast of the colors, forms, textures
and to have the music of the pots too is almost more beauty than I can bear.
Enjoy. Jeri<<
This post reminded me....recently I fired my first load of crackled pots. I
had
only before tested the crackle glaze on little tiles, so the pinging was
minim
Nothing that I had read prepared me for the experience of the cooling of my
first real load. For more than an hour, it sounded like miniature wind
chimes
as they pinged randomly in different pitches, over and over. It was
magical!!!! I decided the reason that I never read anything about it
was........
it's a potters' secret so as not to ruin the surprise!!!!! A concert by the
teeney tiny Ping Pixies. ;-)
Elizabeth, who can't wait for her next little concert.
>>
Sharon R Pemberton on wed 30 jun 99
Phyllis,
Glaze does not make a pot water tight, firing to clay maturation does that.
The best stoneware still absorbs a small amount of moisture even if you
cannot discern. This is also true for the lower fired clays as well.
From the floor of the desert inferno,
Pug
Mike Gordon on wed 30 jun 99
Phyllis,
If you use a crackle on the outside than it is wise to use another
tighter fitting glaze on the inside. I haven't found one yet at 06, so I
seal the inside with an acrylic varnish. It seems to work in tests so
far. Mike in Walnut Creek, Ca. 102 degrees.
elizabet on thu 1 jul 99
Phyllis wrote:
>>>I am just so upset after all these years not to have heard the "ping
pixies"...and from a full load too!
Do you hear this after using crackle glazes? I don't use very much
crackle
glazes but if I have to do a full kiln load to enjoy this experience,
then I
want to plan to do so.
If crackle is used and is fired to 06...it won't hold water will
it?....so,
would one use another type glaze for the interior of their ware?<<<
Yes, I hear it after using crackle glazes. I fire to cone 5 but I don't
use it on
functional ware so I'm glazing with crackle inside and out.
Hope you get to hear the Ping Pixies,
Elizabeth
Annie on fri 2 dec 05
I poured molds with Laguna stoneware (grits) slip. I used Spectrum high
fire glazes. When my pieces came out of the kiln they were pinging like
crazy. The kiln was cooled completely before I opened it. Why would the
pieces be pinging? I thought this only happened it you did not let the
pieces cool? Any ideas. Thanks
John Hesselberth on fri 2 dec 05
On Friday, December 2, 2005, at 07:34 AM, Annie wrote:
> I poured molds with Laguna stoneware (grits) slip. I used Spectrum
> high
> fire glazes. When my pieces came out of the kiln they were pinging
> like
> crazy. The kiln was cooled completely before I opened it. Why would
> the
> pieces be pinging? I thought this only happened it you did not let the
> pieces cool? Any ideas. Thanks
Hi Annie,
Pinging is caused by glazes cracking or crazing. While cooling too fast
is one reason they can craze, the basic cause is that your glazes do
not fit the clay body you are using. The glazes have a higher
coefficient of thermal expansion/contraction than the clay body, i.e.
they shrink more on cooling than the clay body does and the glaze
breaks apart.
Unfortunately, since you are using commercial glazes and casting slip
we can't advise you on what to change except to say you will have to
use a different casting slip or different glazes or both. I would call
Spectrum or Laguna directly and ask them for recommendations of a
casting slip/glaze system that will solve your problem. If you mixed
your own glazes we could help you reformulate them yourself for better
'fit' between clay and glaze, but without knowledge of the composition
of the glaze we would just be guessing.
Regards,
John
Annie on fri 2 dec 05
John:
Thank you so much for your quick reply. Since I am using Laguna slip, I
will take your advice and give them a call to see if using their glazes
will solve my problem. I just happened to have found Spectum colors that
I love. Thanks again for the help.
This is just a hobby for me and I run into so, so, many problems. It is
nice to have a place to ask questions. Thanks again.
Annie
Ivor and Olive Lewis on sat 3 dec 05
Dear Annie,=20
This is one of those cases where the glaze does not fit the clay.
All I can suggest is that, if you are compelled by circumstance to use =
ready prepared glazes, that you ask your clay manufacturer for =
suggestions of glazes from their range which will not do this with your =
chosen clay and firing cycle.
If this does not solve the problem start asking more questions.
Best regards
Ivor Lewis.
Redhill,
South Australia.
Diane Palmquist on thu 16 nov 06
----- Original Message -----=20
FromSubject: pinging
Hi all,
Well for lack of a better word I am wondering if anyone could =
enlighten me on an unusual amount of "pinging" that I am experiencing in =
two pieces I have. I unloaded them from the cone 6 firing 3-4 weeks ago. =
They are loudly making this noise-I can hear it in the other room. It is =
not a constant but a daily ritual. I am not always close by so I really =
can't say how often it is occurring but I notice it in the evening when =
I am settled down from a long day of work! So the question for me is-why =
and any other concerns about these pieces?
Thanks,
Diane
John Rodgers on thu 16 nov 06
Pinging will occur with virtually all pottery, some more that others.
It's related to the releiving of stresses in the pottery piece after
firing.. It is mostly - maybe all - related to the fit of the glaze to
the clay. Good fit - minimum pinging. Not so good a fit, then it might
ping forever.Sometimes that pinging is the fore runner to a lots of
problems - Shivering of the glaze and crazing of the glaze. The strain
on a pot where the glaze does not fit can crack a bowl in half. BTDT!!
Had a large bowl sitting on the table - a day or so after it came out of
the kiln - when there was a loud "Ping!" and then this death rattle as
the bowl halves rocked back and fourth on the table top. When I went to
look for this strange sould, there was my bowl - split in to.
Regards,
John Rodgers
Chelsea, AL
Diane Palmquist wrote:
> ----- Original Message -----
> FromSubject: pinging
>
>
> Hi all,
> Well for lack of a better word I am wondering if anyone could enlighten me on an unusual amount of "pinging" that I am experiencing in two pieces I have. I unloaded them from the cone 6 firing 3-4 weeks ago. They are loudly making this noise-I can hear it in the other room. It is not a constant but a daily ritual. I am not always close by so I really can't say how often it is occurring but I notice it in the evening when I am settled down from a long day of work! So the question for me is-why and any other concerns about these pieces?
> Thanks,
> Diane
>
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>
Dave Finkelnburg on fri 17 nov 06
Diane,
You are hearing either crazing or shivering. Yes,
shivering can make pings, too, though the odds are you
have crazing. Delayed crazing due to absorption of
atmospheric moisture causing the ceramic body to swell
slightly may be at work.
You do understand what crazing is, I am sure, but
for those who may not, it is simply a case where the
glaze is stretched too tight to fit the clay body
after the two are fired together.
How does this happen? First, remember at the end
of a firing (before the kiln cools) the glaze has
melted into a glass, admittedly sometimes with
crystals in it. The body has never fully melted, and
is a mix of raw materials like quartz or grog,
possibly crystals of aluminum silicate called mullite,
and a glass phase. The point is, the body and the
glaze are together, but they are not the same, and
thus they may not fit together perfectly once they
cool down.
Both body and glaze begin to cool, and shrink.
(Note: I have been told by those with much more
potting experience than the little I have that only
clay bodies shrink, that glazes "contract." I think
you get the picture)
The clay and glaze cool and slowly get slightly
smaller. At some point the glaze freezes to a brittle
solid.
This is where it gets interesting. The body keeps
cooling, and shrinking, until it's at room
temperature. At this point the glaze has either
contracted as much as the body (perfect glaze-body
fit!), or less than the body (glaze is in compression,
may shiver) or more than the body (glaze is in
tension, may craze).
In your case the glaze is likely in tension, though
from your description, only a little. Thus it slowly
cracks from not being able to stretch over the ceramic
body. Brittle materials just don't stretch. The
pinging you hear is the sound of the glaze cracking.
Excessive glaze compression can cause the glaze to
crack...you'll usually see bits of it literally pop
off the rim or some other edge if that is happening,
and that is called shivering. Like crazing, shivering
is also audible.
No, I won't comment on whether crazing is good or
bad. Those worms won't fit back in the can! :-)
Good potting,
Dave Finkelnburg
--- Diane Palmquist wrote:
> Well for lack of a better word I am
> wondering if anyone could enlighten me on an unusual
> amount of "pinging" that I am experiencing in two
> pieces I have.
____________________________________________________________________________________
Do you Yahoo!?
Everyone is raving about the all-new Yahoo! Mail beta.
http://new.mail.yahoo.com
Ron Roy on fri 17 nov 06
The implication in the statement below is that all pottery will either
craze or shiver - that is not true.
I have seen many ancient pots in museums that are neither crazed or shivered.
The bowl mentioned below suffered from shivering - - the glaze expansion
was so much lower then the clay expansion that the inside glaze forced the
bowl apart. Saying it that way makes it more difficult to understand than
if I say -
During cooling the glaze contracted less than the clay - with the glaze
winding up too "big" for the clay.
The opposite (crazing) is when the glaze contracts more then the clay
during cooling and has to break up (craze.)
What is most likely happening to Diane - pinging for days after it's out of
the kiln - is crazing - the fact that it is still happening also means it
is almost a good clay glaze match and will be relatively easy to fix.
If it is shivering - a good way to find out is to freeze the piece - that
continues the cooling and will make any mismatch worse. If boiling water is
poured into the frozen ware (in the sink in case it cracks) the inside
glaze will expand a fraction of a second before the clay. If the glaze is
already too "big" for the clay the ware should crack if it's going to.
RR
>Pinging will occur with virtually all pottery, some more that others.
>It's related to the releiving of stresses in the pottery piece after
>firing.. It is mostly - maybe all - related to the fit of the glaze to
>the clay. Good fit - minimum pinging. Not so good a fit, then it might
>ping forever.Sometimes that pinging is the fore runner to a lots of
>problems - Shivering of the glaze and crazing of the glaze. The strain
>on a pot where the glaze does not fit can crack a bowl in half. BTDT!!
>Had a large bowl sitting on the table - a day or so after it came out of
>the kiln - when there was a loud "Ping!" and then this death rattle as
>the bowl halves rocked back and fourth on the table top. When I went to
>look for this strange sound, there was my bowl - split in to.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Ivor and Olive Lewis on sat 18 nov 06
Dear Diane Palmquist,=20
The sound you are hearing is your glaze cracking. This is because it is =
still trying to contract even though it is cold. After your work has =
matured and the cones have done their work both clay and glaze are still =
plastic and can move relative to each other. But below a certain (But =
probably unknown ) temperature called the Glass Transition Point both =
become rigid. But at they continue to cool they both contract. If the =
glaze contracts more than the fired clay it suffers from strong tension. =
But because it is now brittle it has no elasticity. So it snaps. In the =
worst case possible, and this has happened to me, a pot will =
disintegrate as though shot with a rifle.
Potters who make their own glazes try to construct recipes which =
minimise the difference between the Coefficients of Thermal Expansion of =
glaze and clay to eliminate this problem. Some potters encourage the =
effect and call the result Crazing. They accentuate the shatter lines in =
the glaze with black stain, India Ink or black acrylic paint.
There may be cause for concern. If your Cone 6 clay is not fully =
vitrified then you pots may leak if they are used to contain fluids.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
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