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pinging crazing

updated sun 21 aug 05

 

bill edwards on wed 17 aug 05


If anyone here has information that provides health
information where a crazed pot has caused them harm,
please send me that information. Now with that said.

Pots that are crazed are not durable or stable over
the long haul. It doesn't mean you will be poisoned by
it unless there is toxic ingredients in ammounts known
to cause harm upon the human body and that would be
rare under the worst conditions. (don't let this open
a can of worms) There's more dangers to your coffee
mug handle popping off and spilling hot coffee on
someone IMHO than food poisoning or a bacterial
outbreak from a crazed piece of pottery. That fear is
out of place again but I respect those who use it to
train others not to mess up and learn how to calculate
glazes even when they can't get a decent clay
analysis. And it's my opinion not a scientific study.
The reason I asked about that is explained above.
Anyone???? Out there know of another person who has
became ill or sick from a crazed piece of pottery.
This would be good information to have on hand. And
no, I wouldn't use a crazing glaze for stable
functional work where food is going to be placed or
acidic attack be an issue such as in cooking where
tomatoes or something else might be cooked. I wouldn't
trust that good food to potentially getting wasted on
the bottom of the oven for that matter or a pot
popping in someone's hands. Now thats more of a
concern to me and more of a threat! :)

Since clay manufacturers seldom give the potters
expansion charts, its up to the potters to figure out
how to match their glaze as best they can to the clay.
Raise the glaze expansion if it crazes, check for
color loss with vinegar and lemon. (Adding silica
alone isn't always the right answer, there's a balance
to achieve.) While the difference between glaze and
clay can be only slight its something like having a
shell over something that is either too big or too
little. The idea is to get those two pieces to fit
comfortably and uniform with similar contraction and
expansion. Sometimes you will see crazing in heavily
applied areas of glaze and not on the rest of the pot.
(Some drop the rate of cooling too fast or rob their
kilns too early) Thats a sign your close but need to
raise it up another notch to prevent delayed crazing
or let it cool slowly and stop peeping in and looking.
And yes, there's poor teachers. No one can really keep
up with everything but teachers catch heck way too
often. They deal with students, they deal with bosses,
they deal with multiple clay bodies and constantly are
dealing with countless glazes. They wouldn't have time
to teach if all they did was one thing or they would
get fired. So we have to really watch out how we place
things in such a large way to encompass a group, those
that have contacted me are often trying to fix their
problems not make problems worse. I am sure that the
bad apples are out there (I learned the hard way) but
there's always bad where you find honesty and
integrity as well. They often live side by side. I
have seen some really good questions get posed to the
group that I failed to answer for one reason or
another but the new potter gets slammed dunked first
time out and told to go to the back of the line or
check the archives but someone of good faith will
usually beat me to the answer and the other becomes
null and void. The archives isn't always up to date
with todays technical end of things. I am just sorry
that some feel they have to appear as leaders and not
take all that energy they put in a post to conquer a
new potter, but instead use it to teach a new potter
and help them define themselves better. Most of the
time they get great help, some of the time they get a
lashing and yet I am suprized to see it when we talk
negative at all about a teacher without all the facts
and using it in such broad terms. The same can be said
for many here as well. I won't even qualify myself for
a post like this. 9 out of 10 of my responses are
often done one on one. Am I helping anyone at all? But
I feel we can work on our own self images before we
work on some others out there. If you know a really
bad teacher, talk to their boss or tell them head on.
But be sure you are qualified to back up every word
you say.(This is a qualified statement) Wait till you
have had someone steal your glaze book you wrote with
over 30 good glazes and was about to release it and
then hire a lawyer to get it back and then latter
start seeing some of these glazes being sold at
galleries on their pots, then you can get mad. Thats
after them being handed a copy to comply with the
legal end of things such as not using the materials
since the information was obtained through false
means, no copying or reproducing of any kind. These
kinds of teachers, they got to go and fast. Life
happens, it's almost as crazy as some of the things
that go on in clay and glazes and making a match or
marriage though thermal dynamics. I found myself
respecting Ron and John for asking nicely for those
who use their glazes without reproducing the
formulations for a mutltitude of reasons for a period
of time. (Was there a time limit, I know the
information was bought and sold so when will those
recipes become less an issue to publish so others can
rant or rave over them based on formulations?) We
sometimes don't always see the same things in the same
ways but I consider them a friend to the potter as
well as to myself, they worked hard. We all do our
best but there's always something else to consider and
nothing can beat a new potter's questions posed to
this group because its so fresh and often so new and
honest. I'm not being rude today, I am being honest
and making an observation that I have held off doing
for awhile now. I can take the heat better than some
pots out there but I am more non-utilitarian than I am
functional or stable right now. (Just pulling your
leg)Have a great day today and a better one tommorow.

Bill Edwards
Edmar Studio and Gallery
302 South Main St (Shipping)
POB 367 (Mailing)
Camp Hill, Al. 36850
http://apottersmark.blogspot.com/
"!" And I quote that
CampHillBilly

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Wayne Seidl on thu 18 aug 05


Bill:
I've not, to my knowledge, ever been harmed by a crazed pot.
I have questioned my sanity though, after hanging out with
crazed potters! Does that count?

Best,
Wayne Seidl

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of bill
edwards
Sent: Thursday, August 18, 2005 12:01 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Pinging crazing

If anyone here has information that provides health
information where a crazed pot has caused them harm,
please send me that information.

Antoinette Badenhorst on thu 18 aug 05


Well, coming from Africa where conditions are often not sanitized, I do
think one can get ill from crazed ware, but that being said, I do not =
know
of anyone that did get sick because of using crazed pottery. Some ten -
fifteen years ago I discovered that my mom was drinking from one of the =
very
first cups I made in the 80's. Did not look for crazing, but the piece =
were
chipped. I dropped it on the floor and immediately gave her a new one =
that I
did not check to see if it is crazed. She was very shocked and =
disappointed
with me, till I explained to her about all the germs she is taking in =
with
that mug.
I think that experienced potters should have the morality to check for
defects in glazes and inexperienced potters should have an example to
follow. I think we all let crazed pieces slip by. Often times it is not
intentional. Like you mentioned there might be a delayed crazing. Most
potters are not too serious about technicality that the eye can not see. =
It
does not take us off the hook though, but I do think there should be a
balance in anything we do.=20
A while back I had an 80+++ year old client that collect Rookwood and =
other
Americana in my studio. I showed him a tiny crack in a porcelain piece =
I've
made. He bought it with the comment that my honesty about my work might
shoot me in the foot some day.
Let us not shoot ourselves in the foot with dishonesty or too much =
honesty.
Let's do the right thing at the right time.

Antoinette Badenhorst
105 Westwood Circle
Saltillo MS, 38866
www.clayandcanvas.com

Ron Roy on sat 20 aug 05


I tend to agree with Antoinette,

I think there are many potters who say they accept grazing simply because
they cannot fix the problem.

The other side of this is the very real opposite problem - when the
expansion of a glaze is so low that dunting or shivering can be the result.


It is just not that difficult anymore - to know the general expansion rates
of all out glazes - so we can know that to expect with every clay/glaze
combination.

There are many glazes that can be adjusted while keeping them looking the
same. It's not a question of perfection so much as a question of doing a
good job. The benefits should be obvious to everyone.

We have no control over how our pots will be used - it just makes sense to
me that we try to do as good a job as possible - call it professionalism if
you like - just trying to do the job properly.

It is a curious thing - most of the students that take my glaze calculation
courses are amateurs - once on a while a pro will show up - but mostly
those who don't make a living selling their work. It makes me wonder about
the frequent discussions here about who is a professional and who is not.

RR


>I think that experienced potters should have the morality to check for
>defects in glazes and inexperienced potters should have an example to
>follow. I think we all let crazed pieces slip by. Often times it is not
>intentional. Like you mentioned there might be a delayed crazing. Most
>potters are not too serious about technicality that the eye can not see. It
>does not take us off the hook though, but I do think there should be a
>balance in anything we do.
>A while back I had an 80+++ year old client that collect Rookwood and other
>Americana in my studio. I showed him a tiny crack in a porcelain piece I've
>made. He bought it with the comment that my honesty about my work might
>shoot me in the foot some day.
>Let us not shoot ourselves in the foot with dishonesty or too much honesty.
>Let's do the right thing at the right time.
>
>Antoinette Badenhorst

Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513