Ivor and Olive Lewis on sat 15 jul 06
Dear Fred Parker,
You tell us <<....In my short adventure into clay and glazes I have been =
puzzled by a single
question: with all the exposure I have had to chemistry and chemical =
engineering, and with all the books I have read on glazing (including =
yours), and with all the test glazes I have mixed and tried (I'd =
guestimate around a hundred at this point), why does glaze "chemistry" =
still seem like voodoo to me?...>>
Fred, the simple answer to that question is that you are primarily =
trained as a scientist and not as an artist. Therefore you seek the =
rational and not the irrational. You understand the precise but not the =
nebulous.You are in the position of Galileo Galilie who was told by the =
Inquisition that so many Pope's could not be wrong. Heaven revolves =
about the Earth and must continue to do so. Dogma.=20
Your request to John for a <<...universal format for communicating =
glazes...>> would perpetuate the Voodoo and not lead to an understanding =
of the complexity of Glaze Science or reveal the principles that are =
currently ignored or are misrepresented in much of the literature =
published for Studio Potters.
I am, by the way, a great advocate of "Mastering Cone Six Glazes". John =
and Ron have given a new generation of studio potters a basis for =
understanding and exploration. Their format does not "Perpetuate the =
Voodoo". I use a different system and my first step is to mix a hundred =
and eight samples when I search for specific qualities.
There are many question to solve. I hope you are able to make a unique =
contribution by applying your scientific training to debunking Dogma =
from the past.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Fred Parker on sun 16 jul 06
Dear Ivor Lewis:
At the risk of being grossly misunderstood, let me attempt to clarify a
couple of the points I made, and correct a misinterpretation I believe you
might have made also. Let's do you first:
Most of my training/education is in architecture -- not science. I was a
practicing architect for many years, and although science is involved in
architecture, its basis is significantly more in art than science. My
science comes from my younger years wandering through the deliciously
tempting gardens of academia trying to learn everything there was to know
about everything -- something I would still enjoy doing today given the
resources to do so. I was fortunate to have an interest in chemistry --
and later, in chemical engineering, in addition to art -- before an event
in Southeast Asia abruptly changed my journey by snatching me into the
jaws of reality for a four year, all-expense paid side trip with the U.S.
Air Force during the 1960's. When I finally received my five-year B.Arch
degree, I learned through the "registrar's check" that I had 170 "excess"
academic hours beyond what I needed for my degree. Much of that came from
a penchant to take courses I had an interest in, and many of those were in
the art department, a sister department to architecture in the "school of
architecture and fine arts."
So, today I do not regard myself as a scientist; rather, some kind of lost
soul wandering between the abstractions, fantasies and freedoms of the
Fine Arts on the one hand, and what is probably a better understanding of
science and engineering than most artists have. In one way, I am
fortunate. In another, I am lost in the surging tides of artistic
freedoms constantly agitated by the scientific realities that step in when
my imagination begins heating up.
When I asked John,"...In my short adventure into clay and glazes I have
been puzzled by a single question: with all the exposure I have had in
chemistry and chemical engineering, and with all the books I have read on
glazing (including yours), and with all the test glazes I have mixed and
tried (I'd guestimate around a hundred at this point), why does
glaze "chemistry" still seem like voodoo to me?..." I was indirectly
commmenting on the point he made in his original post -- that glazes are,
for the most part, communicated as "cookbook recipes" without the "how to"
section. Even in chemistry, reaction are often shown with symbols
indicating reaction conditions, whether catalysis is required,
exothermicity or indothermicity etc. Yet in glaze "alchemy", where much
seems to be happening at the physical and chemical levels -- and where
many, many conditions yield vastly different results, we traditionally see
only an ingredients list.
I believe it is time for change now (and I did not read your message as
disagreeing with this). When I suggested to John that he consider
developing a "universal glaze format" I meant it -- no Voodoo included. I
must vigorously disagree with your comment that such a format "...would
perpetuate the Voodoo and not lead to an understanding of the complexity
of Glaze Science or reveal the principles that are currently ignored or
are misrepresented in much of the literature published for Studio
Potters." To the contrary, a well thought out format, universal and
globally recognizable by potters everywhere would go a long way toward
eliminating the fog surrounding glaze chemistry today. There is simply no
way providing more information about a glaze, its reactive content, proper
mixing, application and firing conditions -- and doing so in a consistent
format -- would "perputuate the Voodoo" compared to today's standard (also
a type of "universal glaze format", incidentally) which tells a potter
nothing beyond ingredients and relative amounts.
I suspect, when it comes down to it we are probably saying the same
thing. I am not always the clearest of communicators and I will never use
those little symbols to indicate if I am speaking tongue-in-cheek,
grinning, angry or sitting on the can as I write, so let me apologize for
any misreading I might have caused. I'm glad you commented on my
suggestion, and I hope others will also. I am convinced it is needed.
Finally, just in case my message miscommunicated my opinion of "Mastering
Cone 6 Glazes" let me clarify that misconception. I have read the book at
least two-and-a-half times, believe it is certainly among the most
informative on the market (I have not read them all) and have nothing but
respect and admiration for its authors. I would like to see more of their
clear thinking published in an expanded book on glazes, and I recommend
MC6G to anyone interested in learning more than how to set up a line blend
or some other trial-and-error studio experimental approach.
Thanks for thinking,
Fred Parker
Alisa Liskin Clausen on sun 16 jul 06
and I recommend
>MC6G to anyone interested in learning more than how to set up a line blend
>or some other trial-and-error studio experimental approach.
>
>Thanks for thinking,
>
>Fred Parker
>
Dear Fred,
In my experience, a line blend, simple where you keep one constant and
increase one other material, or more complex like a Currie Grid, are not
trial and error. They are controlled tests to see how materials influence
the glaze. A Brian Gartside experiment with just two materials at 50/50%
will also tell you a lot. The key is at least four fold:
Learning what groups the materials fall in and understanding their
influence in a glaze.
Looking at the results, and discovering which material(s) caused which
surface effect.
Learing how groups of materials work in relationship to each other, on
order to develope your recipes.
Glaze calculation will show you characteristics you cannot see, in order
to adjust COE or sil:alum. or how to get the glaze also visually altered
to your needs, via levels of glass, Calcium, etc.
I think trial and error is unguided or guess work, with little chance
other than luck, to get you results. Then it would be difficult to
reproduce those results or even work further with them if you did not have
systematic tests and good notes. On the contrary, line blends are an
important equal partner to glaze calculation.
But, we all have our own methods, just that we keep going further in our
interests.
Regards from Alisa
John Hesselberth on sun 16 jul 06
Hi Ivor, Fred, Mel, and everyone else who commented on this thread,
Thanks to all of you. It has been interesting to sit back for a few
days and watch the comments fly. I had to slap my hands a couple
times to keep them from trying to respond for me sooner. I obviously
did hit a couple people's nerves, but that is OK. Harsh responses
have never bothered me and there is sometimes a gem of insight hidden
in the outburst.
I do have a point to make in that I hate to see potters continue to
struggle and get frustrated with glazes. I have had a number of
workshop participants tell me it is the one area in the world of
pottery that is always a crap shoot with them--and a very frustrating
one with a high failure rate. I contend that doesn't need to be.
The golden age of research into glazes ended in about 1960. That is
when most ceramic scientists turned their attention to more glamorous
applications like space, electronics, and medicine. That is not
likely to change. So if we potters want to continue to develop better
understanding and get better success rates with glazing/firing we
will have to do it ourselves. Each of us as we mix glazes, apply
them, and fire our pots learns a bit about those glazes and how to
use them successfully. Those learnings are probably not highly
scientific but they often could help other potters and, taken
collectively, could slowly help us advance the knowledge base
together. But when we just communicate the recipe, and nothing else,
we fail to communicate any of the learning. It is lost--maybe even to
the person who learned it because they have not consciously thought
about what they learned and documented it in their notes. On the
other hand, there are some on Clayart who conscientiously document
their work and do report their learnings--Alisa is one of the best at
doing that and I applaud her efforts--we all do judging from the
positive comments that flow in after she posts her latest tests.
As a start, that is all I would ask for--just some descriptive text
telling people what you think is important to know about successfully
mixing, applying and firing that glaze. Now is that really so hard to
do?
Fred, I have shied away from trying to develop a specific format for
people to use. One thing I have learned since becoming a full time
potter a decade ago is that quite a few potters rebel and dig their
heels in against anything that smacks of "formality" or "systems".
You saw some evidence of that in the initial outbursts to my note.
True there are others who would appreciate having a format to work
with so I could just say "screw it", let the rebels rebel. The rest
of us have work to do. And the time may come when I try that
approach, but I'd rather win by seduction if I can.
And I think I can. Potters as a class are a group of very
intelligent, observant people. Furthermore we are a sharing group--we
enjoy helping each other. I suppose some of us might be concerned to
share our observations out of worry that we might be told we are
wrong by some self-appointed "expert" (who really is not), but my
experience on the list is that we have run most of those folks "out
of town" by now. It certainly seems better to me than it was about 8
years ago when I first found Clayart. And besides we can now count on
Lili to reign them back in when they get too high on their high
horse. How can you go wrong with Lili on your side?
I have gone on long enough so I will just end by saying that it has
been a useful discussion for me and I have more hope that I will
begin to see more descriptive sentences or paragraphs accompany the
recipes that are posted from time to time.
And yes, I'll probably poke a stick at this subject sometime again in
the future. I try to be predictable!
Regards,
John
Fred Parker on sun 16 jul 06
Hi Alisa:
I didn't mean to suggest that a line blend is trial-and-error. I should
have crafted my sentence more clearly. I see a huge gulf between applying
a scientific method -- such as a line blend procedure -- to a given
formula, and actually understanding the dynamics behind the results
produced. What I was trying to say was more like "...to anyone interested
in learning more about what is actually happening in the glaze firing than
can be learned in a line blend -- or, for that matter, some trial-and-
error approach..."
Apologies for the misunderstanding. By the way, thanks for your
incredible committment to testing and sharing glaze information. It
didn't take long to see the quality of your posts, and to glean much very
good information from them. Several of my tests have included glazes you
reported positively on.
Maybe you already have the "universal format" figured out?...
Regards from the Deep South, USA.
Fred Parker
On Sun, 16 Jul 2006 13:32:09 -0400, Alisa Liskin Clausen
wrote:
>and I recommend
>>MC6G to anyone interested in learning more than how to set up a line
blend
>>or some other trial-and-error studio experimental approach.
>>
>>Thanks for thinking,
>>
>>Fred Parker
>>
>
>Dear Fred,
>In my experience, a line blend, simple where you keep one constant and
>increase one other material, or more complex like a Currie Grid, are not
>trial and error. They are controlled tests to see how materials influence
>the glaze. A Brian Gartside experiment with just two materials at 50/50%
>will also tell you a lot. The key is at least four fold:
>
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