Jim Brooks on wed 22 feb 06
Once glaze recipes..or most anything else..are published, they become.. for
all practical intent -- open to the public.,Ianyone can read the
publicatioin.) . An individual may make a copy for his/her personal use/ work page/copy
etc. He/she may not make copies for commercial use, resale, use in other
publications etc....nor may he/she make a profit directly from that copy.. If
multiple copies are needed ..such as for a school classes, then usually the
copier (user) can obtain permission to reproduce copies for that purrpose
only.... ONLY...
Posting a glaze recipe on the internet --to an indivudual --does not
violate copyright laws....unless it generates income or become a commercial venture.
Veena Raghavan on wed 22 feb 06
In a message dated 2/22/2006 9:14:58 PM Eastern Standard Time,
ronroy@CA.INTER.NET writes:
>
> John and I have more work to do - and we support our book - daily - it
> takes time and effort - we are proud of what we have done and are doing -
> and we thank those of you who have supported us so well and so often.
>
--
Ron (and John),
In reply to Ron's post, which I do not quote in its full length, although I
suggest everyone access it and read it, if they have not already done so. you
have said it all!
I think many of us need to understand more about glazes, although so many
clayarters are very knowledgeable on the subject, there are those of us who have
much to learn. I include myself in the latter group. Thanks to Ron, John, Tom
Buck, John Britt,and many others (too many to name), I have learned a lot, but
have a long way to go. I understand much more than I did a few years ago,
thanks to all of you, those who question and those who answer.
Thank you all, and thank you, Ron for your post.
Veena
VeenaRaghavan@cs.com
Ron Roy on wed 22 feb 06
When John and I were talking about writing a book we both had strong
feelings about what we wanted to do. It was as if we were of the same mind
and that has carried through the whole process. We still agree to a degree
that is remarkable - we are a team.
One of the problems we set out to improve was the way that glaze recipes
were tossed around - shared - with little infomation going with them. We
wanted to change the way things are done so that potters would have a
better chance of being successful - and would not discourage sales of
pottery due to pots that did not do what they are supposed to do. It is not
just the posting of our recipes that we feel that way about but the great
majority of glazes published everywhere.
We can see from the posts on ClayArt over the last few weeks that many of
you get it - that this is about making it better for everyone - not
painless - but an improvement.
We also see that there are some who still don't get it - and may never get
it - and I am not surprised. What does surprise both John and me is how
many do get it and how much we have all learned along the way.
It may have gotten lost but we have never said - don't post the molecular
formula of our glazes - in fact that is a good way to compare glazes if
what you want to know about is stability, hardness, firing temperature,
colour response and expansion.
In the end I still have reservations about posting recipes without the
addition of some important infomation. If you ask me directly I would say I
would rather you not - because I know that the opportunity to educate
vanishes at that point.
I cannot stop anyone from publishing any glazes - even ours - but I think
there has to be a better way and I believe we should be working toward a
better system.
Trying to change things is never easy - old ways die hard. The trick is to
keep what is working and productive and change what is causing problems -
no mater who's self interest is involved.
John and I have more work to do - and we support our book - daily - it
takes time and effort - we are proud of what we have done and are doing -
and we thank those of you who have supported us so well and so often.
RR
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Steve Slatin on thu 23 feb 06
Rather than all the sniping .....
This is a suggested format, that's all -- I've got
no committment to it, but let's consider it and
see if there's something better or if we can
start here.
Layout --
A. Author, name, cone, color, atmosphere,
surface
B. Recipe
C. Analysis
D. Ramp, kiln details
E. Clays used in testing
F. Comments
This is lots longer than what John B. (throw away
all of my grits) envisioned, but includes enough so
the glaze may be replicated and understood.
Example --
Author -- Steve Slatin
Recipe Name: Tarnished yellow
Cone: 6 Color: clear dark yellow, white where thick
Firing: Oxidation Surface: Glossy
RECIPE
Amount Ingredient
25 Feldspar--Custer
25 Frit--Ferro 3134
20 Silica
20 Kaolin--EPK
10 Dolomite
100 Total
Additives
8 Rutile
ANALYSIS
Unity Oxide
.192 Na2O
.098 K2O
.185 MgO
.524 CaO
1.000 Total
.414 Al2O3
.295 B2O3
.005 Fe2O3
3.444 SiO2
.003 TiO2
.001 P2O5
8.3 Si/Al Ratio
69.6 COE
Ramp -- 200 F to 200 F, 1 hour, 30 minute hold;
500 degrees per hour to 2000 F, no hold
150 degrees per hour to 2210 F, 20 minute hold,
150 degrees per hour DOWN to 1500 F, 30 minute hold
Unvented kiln, plugs inserted at 1800 on the way up and
removed after kiln drops below 800 on way down.
This is a 'hard' cone 6 ramp, a 6 cone will be tip
touching, a 7 cone will be starting to show a curve.
Clay: Tested with Seattle Pottery Supply Sea Mix 5 and
Goldstone, and Clay Art Center Bennett. Color was muddy
over Goldstone, clear over Bennett and SM-5.
Comments: Holds up well under leach testing. No visible
crazing under 30x magnifier with SM-5, some crazing
over Bennett. Not possible to see if there is crazing
with Goldstone.
That's 44 lines by my count vs. the smaller number John B.
suggests, but maybe it's a point of departure. Comments?
Do people want something more, something else, or
somewhat less?
-- Steve Slatin
John Britt wrote:
Hello David,
Thanks for the nice post.
After reading all these posts about the how futile it is to post recipes I
struck by the fact that ceramics is still alive after all these 28,000
years? But I think you guys are making it much harder than it is. It is
not rocket science or nanotechnology.
Steve Slatin --
In watermelon sugar the deeds were done and done again
as my life is done in watermelon sugar.
---------------------------------
Relax. Yahoo! Mail virus scanning helps detect nasty viruses!
Lee Love on thu 23 feb 06
On Wed, 22 Feb 2006 20:39:32 -0500, Ron Roy wrote:
>In the end I still have reservations about posting recipes without the
>addition of some important infomation. If you ask me directly I would say I
>would rather you not - because I know that the opportunity to educate
>vanishes at that point.
Knowledge, unlike material things, multiplies exponentially as it is
shared. The internet has really opened up knowledge from all places and all
times.
Our society seems to have turned to treating its members
paternalistically. Maybe it is good pedantically, in the education of
young children. But adults need not be treated this way. It is important
to trust folks to know what is best for them.
>I cannot stop anyone from publishing any glazes - even ours - but I think
>there has to be a better way and I believe we should be working toward a
>better system.
Good luck! I hope you will take into consideration and make room for
traditional, non-industrial methods too.
Hey folks. I am working on some cadogan teapots. See some photos of
historic ones here: http://hankos.blogspot.com/
--
Lee Love
in Mashiko, Japan http://mashiko.org
http://seisokuro.blogspot.com/ My Photo Logs
http://ikiru.blogspot.com/ Zen and Craft
"Imagination is more important than knowledge."
--Einstein
John Britt on thu 23 feb 06
Ron,
Thanks for the reply.
The trouble on this side of the discussion is that John lifted the ban on
publishing the recipes (which I posted to you earlier) and now you are re-
imposing it.
No matter, that is your prerogative but at least now we know. Glad I asked!
You write: "It may have gotten lost but we have never said - don't post
the molecular formula of our glazes - in fact that is a good way to
compare glazes if what you want to know about is stability, hardness,
firing temperature, color response and expansion."
I think it would be great if you posted the molecular formula so we could
compare and talk about those things listed above. I would do it myself but
after reading Mel's warning about copyright and not wanting to be sued it
may be best if you posted them.
That would be very educational although the entire discussion has been
educational!
Thanks,
John Britt
www.johnbrittpottery.com
Kathy Forer on thu 23 feb 06
On Feb 22, 2006, at 10:51 PM, Jim Brooks wrote:
> Once glaze recipes..or most anything else..are published, they
> become.. for
> all practical intent -- open to the public.,Ianyone can read the
> publicatioin.) . An individual may make a copy for his/her
> personal use/ work page/copy
> etc. He/she may not make copies for commercial use, resale, use
> in other
> publications etc....nor may he/she make a profit directly from
> that copy.. If
> multiple copies are needed ..such as for a school classes, then
> usually the
> copier (user) can obtain permission to reproduce copies for that
> purrpose
> only.... ONLY...
> Posting a glaze recipe on the internet --to an indivudual --does not
> violate copyright laws....unless it generates income or become a
> commercial venture.
The last part of this statement is wrong and the first part about
open availability has questionable repercussions. A museum is owned
by the people of a city and open at certain admission times, that
doesn't allow the citizens to take pieces home with them -- would
that were the case!
Once copyrighted, something is available to the public but not for
reuse or appropriation. Its availability is limited to the practical
issue of access. Posting something in entirety without quotation or
permission to the Internet or to a large mailing list, even without
commercial intent, or even with copyright notice fully visible, does
violate copyright law. And more than law, it violates the ownership
of the intellectual property. Some would argue for some kind of
medieval bazaar where all ideas are owned and shared equally, but
we're not there.
What would be the purpose of copyright if it entitled any and all to
reuse the work, even without profit? What you seem to be describing
is public domain, not copyright for which permission of the author is
required for any publication beyond the strictly personal.
Even reposting of copyright material to a mailing list for ostensible
public education isn't allowed with copyrighted material. You may
quote salient points, but without permission there is violation.
There is something known as "Copyleft" and could be what you would
like copyright to be, but it isn't, and shouldn't be, legally,
morally, technically.
These links might help:
10 Big Myths about copyright explained
http://www.templetons.com/brad/copymyths.html
Copyleft http://www.gnu.org/copyleft/ and wiki/Copyleft>
Curiously, Wikipedia notes that
"Typefaces
In the United States, typeface designs are not covered by copyright,
but may be covered by patents if sufficiently novel."
Kathy Forer
John Hesselberth on thu 23 feb 06
Some additional thoughts on this subject.
When I started mixing my own glazes nearly 30 years ago I scrounged
recipes from most anywhere I could find them. I mixed them, applied
them, fired them and accumulated a large assembly of the ugliest
glazes I had ever seen. Maybe 1 in 10 or 1 in 20 was worth pursuing.
I wasted a lot of time and got very frustrated following this path. I
suspect many potters have started the same way.
When I joined Clayart nearly 10 years ago it was regularly said
"glazes don't travel well" meaning that it was difficult to reproduce
another person's glaze by mixing it and firing it yourself. There are
many posts in the archives in the late '90s that made that point. And
that's not to count all the problems people have had with a glaze
like Floating Blue over the years. Just think how much agony could
have been spared to thousands of potters if 1) the composition of
Floating Blue had been well specified (it contains a lot of Gerstley
Borate which is one of the most variable materials we work with) and
2) it had been recognized that it required special attention during
firing (does better at cone 5 with a quick cool if I remember--I
don't pay a lot of attention to that one).
We now know glazes travel just fine from potter to potter if the
whole system is well defined and duplicated reasonably closely. MC6G
glazes are in use by thousands of potters in at least 20 or 30
countries around the world with a very high success rate. We have
also helped hundreds of potters modify them to use their local
materials or to better fit their clay body. We believe we have
conclusively demonstrated that, while publishing the recipe alone is
virtually useless, publishing the system description including the
unity formula, "a" recipe that results in that unity formula, how it
was mixed and applied, the clay body it was applied to, the firing
conditons, and anything else that seems relevant can result in very
high success rates by potters trying to match the glaze.
Further, with a positive early experience in mixing glazes, they
then begin to build enough confidence to go forward and modify the
glaze and make it their own--Taylor made that point very well just a
couple days ago. I just had a person send me some photos of test
tiles--he had nailed several of the glazes on the first try and I was
able to suggest a couple things on the one or two he was having
trouble with. He is a relative beginner and was having a positive
experience with glazes instead of a frustrating one like I had
initially. Try to get that success rate with the recipes in Chappell
or Conrad or CM or CT where only the recipe and the cone are given. I
never could and heaven knows I tried in the early years.
I tend to cringe when any recipe is just thrown out of Clayart with
no additional information. To be blunt, my opinion is that it just
adds more garbage to the archives to cause trouble for future
potters. That is why you will see Ron or me or someone else of like
mind often at least try to interpret and spell out what some of the
issues or strengths of a given recipe might be. Our hope is that
people will at least read enough of the thread to be alerted to some
of what we have written. And maybe even a few will be curious enough
to ask "why do you think that?".
We also still see on Clayart--though it seems to be diminishing a
bit--potters who just want the recipe. Perhaps they are behind in
meeting a class assignment, or in getting ready for a show, or
sometimes even have accepted a commission for a color they have never
made, or maybe they need a Christmas present and it is December 23
and they just finished throwing their mugs and need to match their
mother-in-law's sofa. OK, so maybe that last one is a bit sarcastic,
but it is not far off from some of the requests we seen over the
years. So recipes are offered and the odds are pretty high of another
disaster in the making. Either they won't get what they want or it
won't be suitable for its intended use or whatever. I don't have much
sympathy with these folks because they aren't really interested in
learning the craft--they just want quick and easy answers and we all
know there is no such thing in a craft as technically challenging as
ours, i.e. they just want the recipe. Some are even so forward as to
ask that it be sent off-list so they don't have to waste their time
reading Clayart messages.
So that is why I don't like to see recipes--any recipes--ours or
others--get published on a forum like this with incomplete
information on how to use them. There is enough garbage in the
archives with all our squabbling with each other--I am an optimist
enough to hope we won't add to it with things like under-described
glaze recipes. It is also why I devote a fair amount of time every
issue providing Clay Times with analyses of the recipes published in
that journal. While Polly only publishes a simple rating in the
magazine, I also provide the unity formula (where I have enough
information on the materials involved) and a commentary on why I
rated the glaze the way I did. Those get published (although a bit
sporadically) on the Clay Times web site so at least those interested
can learn a bit more about why I rated the glaze the way I did. Polly
is clearly sticking her neck out in being willing to and interested
in doing this and she deserves a lot of credit for doing so.
But on balance it is to each his/her own. Neither Ron nor I nor
anyone can stop someone from publishing recipes. We know that. It has
happened and will happen in the future. But we can hope that the
quality of what is published is influenced, in this narrow area, by
our protestations for which we usually encounter a lot of flack
although more frequently, in recent times, some indications of strong
support. But I hope that better describes why I get uncomfortable
when bare recipes--anyone's--are published.
Regards,
John
David Hewitt on thu 23 feb 06
In message , Ron Roy writes
>In the end I still have reservations about posting recipes without the
>addition of some important infomation. If you ask me directly I would
>say I would rather you not - because I know that the opportunity to
>educate vanishes at that point.
You may recall that over the years I have expressed the view on Clayart
that publishing recipes on their own is of limited value. Just giving
the firing temperature or cone and whether it is oxidised or reduced is
also not enough for getting similar results as that of the originator.
To start with recipes placed on Clayart are seen by people all over the
world. Their sources of raw materials are not necessarily the same as
the sender. A unity or % wt. formula is really a basic requirement if
glazes are to be successfully 'transported' around the world.
Gerstley borate is a particular problem. It seems to be commonly used in
North America but, while available in the UK, it is not commonly used.
Itsuse has various problems, not least being that It's analysis has
varied over the years, so what was the analysis of the GB used by the
originator of the recipe?
There are a lot of other factors which that can make a glaze work for
someone and not others. For example, what is the clay body and the glaze
application? And then, of course, there is the small matter of the
firing.
I am frequently asked for my oil spot recipe. I give this freely with as
much information as I can, but I know people have difficulty in
reproducing the same results. It, of course, includes some Red Iron
Oxide. When talking with someone who had tried my recipe resulting in
only very small oil spots, I found that she used natural RIO while I
used synthetic RIO. Was this an important matter or not? I am afraid
that I had never thought to mention it.
'Transporting' recipes from one to another successfully is certainly not
just a matter of giving a recipe alone and I have tried to elaborate on
this on my web site under - Pottery Techniques / 'Transporting' Recipes
I am not against posting recipes, but one must appreciate the
limitations if all you can add is the cone to which you fire and if it
is oxidised or reduced. The more information that you can give the
better and this should, wherever possible, include a unity or % wt.
formula.
David
--
David Hewitt
Web:- http://www.dhpot.demon.co.uk
Steve Slatin on thu 23 feb 06
Kathy --
I must respecfully disagree. A recipe is inherently not susceptible
of copyright. AFAIK it has never come up with regard to glaze
recipes, but the much larger market of culinary recipes has dealt
with the claim from time to time, and US courts always side with
the idea that a recipe is reproducible without regard to the
status of the work wherein it is found.
The broad outline for US copyrights can be found in the first
chapters of title 17, USC, on-line through ACCESS GPO
at http://www.access.gpo.gov/uscode/uscmain.html
Sec. 102. Subject matter of copyright: In general
(a) Copyright protection subsists, in accordance with this title, in
original works of authorship fixed in any tangible medium of expression,
now known or later developed, from which they can be perceived,
reproduced, or otherwise communicated, either directly or with the aid
of a machine or device. Works of authorship include the following
categories:
(1) literary works;
(2) musical works, including any accompanying words;
(3) dramatic works, including any accompanying music;
(4) pantomimes and choreographic works;
(5) pictorial, graphic, and sculptural works;
(6) motion pictures and other audiovisual works;
(7) sound recordings; and
(8) architectural works.
(b) In no case does copyright protection for an original work of
authorship extend to any idea, procedure, process, system, method of
operation, concept, principle, or discovery, regardless of the form in
which it is described, explained, illustrated, or embodied in such work.
(Pub. L. 94-553, title I, Sec. 101, Oct. 19, 1976, 90 Stat. 2544; Pub.
L. 101-650, title VII, Sec. 703, Dec. 1, 1990, 104 Stat. 5133.)
I draw your attention especially to part (b). The protection of a work
does not extend to the process or discovery it describes. To put
in simpler terms, Frank Colson's 'Rocky Raku' book is completely
protected, but the idea of making a raku kiln out of a garbage can,
or the materials list he used, or the attachment process for the
fiber, is not. (Just in case you're wondering, I think $16 bucks is
a darn fair price for the language, the step-by-step, etc. that you
get when you buy it, and Frank deserves signal honors for figuring
out how to build any kind of kiln for $50 in materials. If I ever decide
to try it, I'll definitely spring for the book.)
A recipe expressed as a Seger formula or a list of ingredients cannot
inherently be copyrighted. If you express your recipe as a poem, lets
say, or an interpretive dance, or a mime routine, the poem or routine
could be copyrighted and successfully defended -- so, for example,
you could copyright ...
Of feldspar soda, one handful
2 cups of water, dip it full!
And gerstley borate just a little and mix together till it puddle
Of silica, two handfulls put
Besides add C. Clay; stir with foot!
If it should drip so thin as milk,
Add more clay 'til smooth as silk!
(I'm not suggesting you'd want to copyright this!)
But it is nonetheless what's viewed as a 'literary work,' albiet
of dubious quality, and susceptible of copyright.
But a list
2/3 cup Kona Spar
1/2 cup G. Borate
1 1/2 cups silica
add china clay until mixture suspends
successfully with 2 cups of water
Cannot be copyrighted. Likewise a molecular
formula cannot because scientific formulae cannot
be copyrighted.
I believe it's clear that MC6G is sufficient in its literary
qualities to be considered a 'work of authorship' and
there can be no doubt that the work, as a whole, is
protected under the law. A recipe cannot be,
however. A description of how the materials in a
glaze interact during the cool-down stage of a firing
clearly can be protected. Of firing schedules themselves,
I have no opinion.
My apologies for the quality of my work --
I'm pre-heating a bisque load and cleaning
a bathroom today, and I've no time to do
better.
Best wishes -- Steve Slatin
Kathy Forer wrote:
The last part of this statement is wrong and the first part about
open availability has questionable repercussions. A museum is owned
by the people of a city and open at certain admission times, that
doesn't allow the citizens to take pieces home with them -- would
that were the case!
Once copyrighted, something is available to the public but not for
reuse or appropriation. Its availability is limited to the practical
issue of access. Posting something in entirety without quotation or
permission to the Internet or to a large mailing list, even without
commercial intent, or even with copyright notice fully visible, does
violate copyright law. And more than law, it violates the ownership
of the intellectual property. Some would argue for some kind of
medieval bazaar where all ideas are owned and shared equally, but
we're not there.
What would be the purpose of copyright if it entitled any and all to
reuse the work, even without profit? What you seem to be describing
is public domain, not copyright for which permission of the author is
required for any publication beyond the strictly personal.
Even reposting of copyright material to a mailing list for ostensible
public education isn't allowed with copyrighted material. You may
quote salient points, but without permission there is violation.
There is something known as "Copyleft" and could be what you would
like copyright to be, but it isn't, and shouldn't be, legally,
morally, technically.
Steve Slatin --
In watermelon sugar the deeds were done and done again
as my life is done in watermelon sugar.
---------------------------------
What are the most popular cars? Find out at Yahoo! Autos
John Britt on thu 23 feb 06
Hello David,
Thanks for the nice post.
After reading all these posts about the how futile it is to post recipes I
struck by the fact that ceramics is still alive after all these 28,000
years? But I think you guys are making it much harder than it is. It is
not rocket science or nanotechnology.
I wonder what is so difficult about a liner glaze that it cannot be posted
on a list serve and then be fired successfully.
I know it is possible. You don=92t need to know every bit of chemistry,
physics and geology about a glaze to slap it on a pot and get it done. You
may not be able to list the materials in very country on the planet but
surely something must be left to the reader.
Even if it is a difficult glaze surely you can list the firing cycle, the
cone, the atmosphere, thickness of application and the clay body and it
should be possible. Isn=92t this true?
I can=92t think of any glaze more difficult than an oil spot to explain to a=
reduction firing potter and yet I have done it countless time successfully.
Is it possible that you may be underestimating the audience? I have worked
with many a beginner and had great results. I have had a great response to
the recipes in my book and they were all simply laid out.
For example, here is a great clear liner:
27 Feldspar
35 Silica
19 Whiting
19 Clay
It is cone 10 glaze that is fired in about 8 =96 10 hours reduction or
oxidation, applied to about 1/16 =96 1/8 inch thick on bisque ware. On
porcelain it will be transparent white and on stoneware it will be off
white/ gray. If fired in heavy reduction it will be light blue to blue
green.
Now that is succinct and expresses enough information to get the job done.
It does not cover every eventuality and it does not explain that it is a
stable glaze or that it may crawl if it is too thick but you don=92t need
all that to try it out. So a recipe with about 4 lines of text will do the
job. We don't really need the percent analysis, the unity formula or the
molar formula. It would be nice but surely you could fire successfully
without it.
What do you think?
Over doing it a bit?
Glaze Ruler of the Universe (Since Earl Bruner is now the President of
Free Glaze Society)
John Britt
www.johnbrittpottery.com
Elizabeth Priddy on thu 23 feb 06
Well, I just got mc6g on interlibrary loan.
for those that ay that it should all be free,
you can't get much free-er than that. I want
to read it and understand it, still don't want
to shift the focus of my potter's life over
to chemistry and ramps and all that...but I
do want to understand. And it looks a lot like
I will be miles ahead of where I am with regard
to this after I read the book.
I was comfortable with buying glaze, because I
knew enough to understand what the various glaze
ingredients do, and I was not working at a mixing
level because that just ain't fun for me. I find
no joy in doing that part. And until now, no offense
to any other author, I have not had an accessible,
logical, clear academic source for understanding.
Most of the books are just elaborate lists of
formulae, pretty worthless. Like a "Joy of Cooking"
with no knowledge of how an oven works or why sugar
is to be treated as a wet ingredient.
r&j are like the Alton Browns of glaze. And that
is a really good thing (ask a foodie, they know who
he is)
So I have a good read ahead of me and I want to thank
the list for getting me interested in something I had
put aside.
E
Elizabeth Priddy
Beaufort, NC - USA
http://www.elizabethpriddy.com
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Elizabeth Priddy on thu 23 feb 06
What I think is that what you present is your
way. What they present is their way. So ...
People should be free to publish any and all
that is in your book,
and people should respect the wishes of the
authors of their book, and not.
and as the other threads have explained, to
truly present the information in their book,
you would have to copy in so much detail,
maybe more than 300 words, so the copyright
problems would prevail.
Why don't you just post your own variations
to the list and your usage info? That way,
no problem?
oh yeah, you don't DO cone 6. So why do you
seem to care so much about this? Is it just to
be able to say that you won the argument?
Philosophy is the love of knowledge, not the
love of being right, or the love of winning.
Given that, what is the philosophy that you are
arguing for? if you would bring it back out to
an esoteric instead of them specificly, because
we have it from the horse's mouth (what they want)
and I for one, see it as an issue of rudeness at
this point.
It's like in my studio when I have students working.
They use my tools sometimes and although it is
necessary, I can't watch. They do not usually treat
them with the respect that I do. But I have some
that I care deeply about, that I do let them use,
and that I specificly train them to use. And they
do not use them without my permission or without the
training. And that is just how it is.
E
OK that was an obtuse analogy. But it is late and
I have to be up by 6 tomorrow and there is survivor,
and idol, and the olympics to watch before I can
sleep. Even TIVO could not make this easy.
--- John Britt wrote:
It would be nice but surely you could
> fire successfully
> without it.
>
> What do you think?
>
> Over doing it a bit?
>
>
> Glaze Ruler of the Universe (Since Earl Bruner is
> now the President of
> Free Glaze Society)
>
> John Britt
>
> www.johnbrittpottery.com
Elizabeth Priddy
Beaufort, NC - USA
http://www.elizabethpriddy.com
__________________________________________________
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Ron Roy on thu 23 feb 06
This is a good example of the problem.
Under what circumstances would this glaze give fit problems?
Why not say for instance - while the expansion is probaly just right (using
G200 and EPK) for most porcelains - there could well be dunting problems
with any stoneware clay with cristobalite in it.
If Custer is used then the expansion is even lower.
If EPK is used the ratio is only 8.65 and it may not be a clear glaze - if
OM#4 is used the ratio is over 10 and it probably will be clear.
If Cornish Stone and EPK are used then it will break any nunmber of clay bod=
ies.
So why not include a comment on expansion and durability? Why not a warning
that the fast cooling in an elecric kiln will poduce a different looking
glaze than one fired in a gas kiln?
As is there is still a lot more information than is usually given but I
think it needs more.
RR
>For example, here is a great clear liner:
>
>27 Feldspar
>35 Silica
>19 Whiting
>19 Clay
>
>It is cone 10 glaze that is fired in about 8 =96 10 hours reduction or
>oxidation, applied to about 1/16 =96 1/8 inch thick on bisque ware. On
>porcelain it will be transparent white and on stoneware it will be off
>white/ gray. If fired in heavy reduction it will be light blue to blue
>green.
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
=46ax: 613-475-3513=20
Ron Roy on fri 24 feb 06
Hi Steve - I like it - that should be enough for most glazes - what we also
need is a list of potters on clay art who would be willing to help anyone
wishing to post a glaze - to fill in any missing information.
Many are willing to share but don't use a calculation program so would not
be able to fill in the Seger formula, expansion, ratio for instance.
Who amoung us would be available to help? I would be for one.
RR
> Layout --
>
> A. Author, name, cone, color, atmosphere,
> surface
>
> B. Recipe
>
> C. Analysis
>
> D. Ramp, kiln details
>
> E. Clays used in testing
>
> F. Comments
>
> This is lots longer than what John B. (throw away
> all of my grits) envisioned, but includes enough so
> the glaze may be replicated and understood.
>
>
> Example --
>
>
> Author -- Steve Slatin
> Recipe Name: Tarnished yellow
> Cone: 6 Color: clear dark yellow, white where thick
> Firing: Oxidation Surface: Glossy
>
> RECIPE
> Amount Ingredient
>25 Feldspar--Custer
>25 Frit--Ferro 3134
>20 Silica
>20 Kaolin--EPK
>10 Dolomite
> 100 Total
> Additives
>8 Rutile
>
> ANALYSIS
> Unity Oxide
>.192 Na2O
>.098 K2O
>.185 MgO
>.524 CaO
>1.000 Total
> .414 Al2O3
>.295 B2O3
>.005 Fe2O3
> 3.444 SiO2
>.003 TiO2
>.001 P2O5
>
> 8.3 Si/Al Ratio
>69.6 COE
>
> Ramp -- 200 F to 200 F, 1 hour, 30 minute hold;
> 500 degrees per hour to 2000 F, no hold
> 150 degrees per hour to 2210 F, 20 minute hold,
> 150 degrees per hour DOWN to 1500 F, 30 minute hold
>
> Unvented kiln, plugs inserted at 1800 on the way up and
> removed after kiln drops below 800 on way down.
>
> This is a 'hard' cone 6 ramp, a 6 cone will be tip
> touching, a 7 cone will be starting to show a curve.
>
> Clay: Tested with Seattle Pottery Supply Sea Mix 5 and
> Goldstone, and Clay Art Center Bennett. Color was muddy
> over Goldstone, clear over Bennett and SM-5.
>
> Comments: Holds up well under leach testing. No visible
> crazing under 30x magnifier with SM-5, some crazing
> over Bennett. Not possible to see if there is crazing
> with Goldstone.
>
>That's 44 lines by my count vs. the smaller number John B.
> suggests, but maybe it's a point of departure. Comments?
> Do people want something more, something else, or
> somewhat less?
>
> -- Steve Slatin
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
John Britt on fri 24 feb 06
Ron,
First, I want to say that respect both you and John and have nothing
personally against either of you. Having a discussion about differences
does not make us enemies.
But before we get off topic too far, remember that the main topic of this
discussion is still the inequity of us posting recipes and you guys not
posting. And second is the promises you made and have now broked. You are
only as good as your word.
As for your latest post:
This is not a problem. This recipe can be posted, as is and potters can
mix and fire the glaze successfully. Go ahead and add
expansion/contraction. So you can post a recipe in less than a page and
make it work. You have proven it.
The problem is your need to control and list every aspect of the process.
That is unnecessary and impossible. Why didn=92t you list Hiratsu Feldspar
or NZ FW 75? Why didn=92t you list HVAR or Imperial Ball clay? Because even
you couldn=92t physically list ALL the factors.
You cannot control every aspect, nor can you anticipate every possibility.
Thanks for the excellent discussion. I think it has been a good learning
experience for everyone.
I am eagerly waiting for you to post the Seger Formula for your glazes
like you promised --unless you changed your mind.
Best,
John Britt
www.johnbrittpottery.com
David Hewitt on fri 24 feb 06
John,
The example recipe that you give is interesting. I am sure that it has a
wide range of use, but why not give a little more detail?
Why, for example, didn't you say which feldspar? Do you mean that it
will work with any feldspar? Potash Feldspar. Soda Feldspar, Nepheline
Syenite, Custer Feldspar. G200 or Cornish Stone?
Also why not more detail as to what you use as Clay. Should it be EPK or
what I call China Clay N50 or any of the numerous Ball Clays, the
analyses of which vary quite markedly.
If you did have an analysis of your recipe to quote, then a reader with
a glaze program could reformulate this to suit the materials that they
have available.
I appreciate that not everyone has a glaze program or wants to have one,
but if you have, then why not give this information with a recipe.
David
In message , John Britt writes
>Hello David,
>
>Thanks for the nice post.
>
>After reading all these posts about the how futile it is to post recipes I
>struck by the fact that ceramics is still alive after all these 28,000
>years? But I think you guys are making it much harder than it is. It is
>not rocket science or nanotechnology.
>
>I wonder what is so difficult about a liner glaze that it cannot be posted
>on a list serve and then be fired successfully.
>
>I know it is possible. You don’t need to know every bit of chemistry,
>physics and geology about a glaze to slap it on a pot and get it done. You
>may not be able to list the materials in very country on the planet but
>surely something must be left to the reader.
>
>Even if it is a difficult glaze surely you can list the firing cycle, the
>cone, the atmosphere, thickness of application and the clay body and it
>should be possible. Isn’t this true?
>
>I can’t think of any glaze more difficult than an oil spot to explain to a
>reduction firing potter and yet I have done it countless time successfully.
>
>Is it possible that you may be underestimating the audience? I have worked
>with many a beginner and had great results. I have had a great response to
>the recipes in my book and they were all simply laid out.
>
>For example, here is a great clear liner:
>
>27 Feldspar
>35 Silica
>19 Whiting
>19 Clay
>
>It is cone 10 glaze that is fired in about 8 – 10 hours reduction or
>oxidation, applied to about 1/16 – 1/8 inch thick on bisque ware. On
>porcelain it will be transparent white and on stoneware it will be off
>white/ gray. If fired in heavy reduction it will be light blue to blue
>green.
>
>Now that is succinct and expresses enough information to get the job done.
>It does not cover every eventuality and it does not explain that it is a
>stable glaze or that it may crawl if it is too thick but you don’t need
>all that to try it out. So a recipe with about 4 lines of text will do the
>job. We don't really need the percent analysis, the unity formula or the
>molar formula. It would be nice but surely you could fire successfully
>without it.
>
>What do you think?
>
>Over doing it a bit?
>
>
>Glaze Ruler of the Universe (Since Earl Bruner is now the President of
>Free Glaze Society)
>
>John Britt
>
>www.johnbrittpottery.com
--
David Hewitt
Web:- http://www.dhpot.demon.co.uk
Noel Jensen on fri 24 feb 06
1) This discussion is starting to remind me of all the things that I
really loved about corporate America - not!
2) John's Book (/The Complete Guide to High-Fire Glazes, Glazing &
Firing at Cone 10) /is wonderful. His clay work (imho) is also top drawer.
3) Other John's (Hesselberth, that is) and Ron Roy's book (/Mastering
Cone 6 Glazes/) is also great. It's the first book that I purchased in
this incarnation as a potter.
4) If you haven't spent some time with both of these books, I'd
recommend that you make the time in the near future.
Noel Jensen
noeljensen@comcast.net
John Britt on fri 24 feb 06
David,
I agree with you completely.
You could post a more detailed recipe. Sure. I was trying to show the most
bare bones way to post a recipe. It doesn=92t take much. And this method has=
been going on for centuries and is working pretty well.
Every potter is not a retired chemist. I would venture to say that many
potters are artists. They may not, nor do they need to have a computer to
glaze their pots. And when they want to post a recipe to help other
potters they don=92t have to spend all day typing or figuring out every
eventuality that may occur across the globe. That is all I am saying.
It is nice to include the exact feldspar and the exact kaolin. It is nice
to include the formula and the exp/cont. but that is not absolutely
necessary.
Nice talking with you,
John Britt
www.johnbrittpottery.com
Sam Hoffman on sat 25 feb 06
Hi Ron & All-
I'm happy to help on the cone 10 and the cone 1 front, both
oxidation and reduction. I think the work that has been done on
glaze calc and testing in the past 10 years is absolutely
astounding. Authors like yourself and Frogpond John, Ian Currie,
John Britt, Robin Hopper, etc. have been exceedingly generous in
explaining your methods. Combining some of these new texts with the
old classics (Rhodes, Tichane, Leach, Cardew) really gives a lot to
work with. Computers have certainly advanced our field.
That being said, I think Lee Love is right on with his impressions
of historical glaze formulation. No refined materials, no glaze calc
programs, no oxyprobes, amazing glazes. Formulation and calculation
can take us so far; nothing like firing a kiln load of pots to see
what you REALLY have. Thanks to Mel for driving this point home. It
really takes the same time to fill a kiln with cups as it does to
fill a kiln with test tiles.
Anyway, cooperation is what really drives our field forward; this
list really facilitates this kind of dialog.
Peace,
Sam
S.L. Hoffman Pottery
Corvallis, Oregon
www.samhoffman.com
On Feb 24, 2006, at 8:30 PM, Ron Roy wrote:
> Hi Steve - I like it - that should be enough for most glazes - what
> we also
> need is a list of potters on clay art who would be willing to help
> anyone
> wishing to post a glaze - to fill in any missing information.
>
> Many are willing to share but don't use a calculation program so
> would not
> be able to fill in the Seger formula, expansion, ratio for instance.
>
> Who amoung us would be available to help? I would be for one.
>
> RR
Steve Slatin on sat 25 feb 06
Ron --
I can do several a day if need be; once we settle on a template
it shouldn't take too long. Or I can just do the calc for a
potter who wants to do the rest and just needs the Seger,
COE, and so on.
I see Sam H. has already offered to help as well; Lee
L has raised a question about recipes that aren't standardized
to begin with and while I can see a simple way to get there
for people who use his method (wet measure) and who
start with refined materials, I can't think of what to do with
a material of unknown constituents (i.e. 'clay from the hole
where the apple tree used to be') but I'd suggest we can
start with what we know and fill in blanks as we go along.
I do think we should consider which measure of COE we
collectively are most comfortable with, and so on. As for
comments others have made about specificity (that is,
what to do if the glaze recipe calls for 'spar' and doesn't
specify which one) I'd prefer that we only publish glaze
recipes that have actually been made, and we can just
fill in whatever class of material we actually used.
Last note -- if we start to do this, less than fully successful
recipes could also be posted, as they add to the information
base. (The 'tarnished yellow' I posted wasn't interesting
enough to pursue further for me, but it vitrified well, and
stood up to the lemon juice test.)
I don't know how many people are out there who'd want
to contribute a recipe but who can't do the calculations,
but I'd suspect it's not that great a number. It might only
take a few folks to get the thing working.
Best wishes -- Steve S
Ron Roy wrote:
Hi Steve - I like it - that should be enough for most glazes - what we also
need is a list of potters on clay art who would be willing to help anyone
wishing to post a glaze - to fill in any missing information.
Many are willing to share but don't use a calculation program so would not
be able to fill in the Seger formula, expansion, ratio for instance.
Who amoung us would be available to help? I would be for one
Steve Slatin --
In watermelon sugar the deeds were done and done again
as my life is done in watermelon sugar.
---------------------------------
Yahoo! Mail
Bring photos to life! New PhotoMail makes sharing a breeze.
David Hewitt on sun 26 feb 06
Ron and Steve,
I am always happy to convert recipes to formula if anyone asks, but I
would always give a proviso that the answer is based on the analyses of
the raw materials that I use in my glaze program. For example the
analysis of the recipe that Steve gives below comes out slightly
differently for me:-
K2O .097
Na2O .190
CaO .519
MgO .194
Al2O3 .405
B2O3 .289
Fe2O3 .004
SiO2 3.497
TiO2 .003
P2O5 .001
Al2O3/SiO2 1/8.64
COE 4.197 English & Turner x10-6/oC Linear
6.839 McLindon x10-6/oC Linear
6.048 Appen x10-6/oC linear
You may well think that the differences in the analysis in this instance
are not significant, but one should appreciate that this can occur and
would probably be more pronounced if gerstley borate was one of the
ingredients. Unfortunately so many North American recipes seem to use
this very variable material.
The differences in the COE are more important. If you do quote a figure
it is important to say whose figures it is based on and the units. Steve
gives 69.6. Obviously the decimal point has been moved one place, but
the figure would suggest that it is based on McLindon. Without such
clarification the quoting of COE figures could be very misleading.
While I have been arguing for the maximum information to be given when
one does post a recipe, I would not like to think that voicing such an
argument would put off people giving only a recipe because they did not
have an analysis. In the end, if you wish to try a recipe, however much
information you have to start with, it must be tested and adjusted, as
necessary, to suit what you want. Giving an analysis would help some one
with a glaze program to get to that end point more quickly.
David
In message , Ron Roy writes
>Hi Steve - I like it - that should be enough for most glazes - what we also
>need is a list of potters on clay art who would be willing to help anyone
>wishing to post a glaze - to fill in any missing information.
>
>Many are willing to share but don't use a calculation program so would not
>be able to fill in the Seger formula, expansion, ratio for instance.
>
>Who amoung us would be available to help? I would be for one.
>
>RR
>
>
>> Layout --
>>
>> A. Author, name, cone, color, atmosphere,
>> surface
>>
>> B. Recipe
>>
>> C. Analysis
>>
>> D. Ramp, kiln details
>>
>> E. Clays used in testing
>>
>> F. Comments
>>
>> This is lots longer than what John B. (throw away
>> all of my grits) envisioned, but includes enough so
>> the glaze may be replicated and understood.
>>
>>
>> Example --
>>
>>
>> Author -- Steve Slatin
>> Recipe Name: Tarnished yellow
>> Cone: 6 Color: clear dark yellow, white where thick
>> Firing: Oxidation Surface: Glossy
>>
>> RECIPE
>> Amount Ingredient
>>25 Feldspar--Custer
>>25 Frit--Ferro 3134
>>20 Silica
>>20 Kaolin--EPK
>>10 Dolomite
>> 100 Total
>> Additives
>>8 Rutile
>>
>> ANALYSIS
>> Unity Oxide
>>.192 Na2O
>>.098 K2O
>>.185 MgO
>>.524 CaO
>>1.000 Total
>> .414 Al2O3
>>.295 B2O3
>>.005 Fe2O3
>> 3.444 SiO2
>>.003 TiO2
>>.001 P2O5
>>
>> 8.3 Si/Al Ratio
>>69.6 COE
>>
>> Ramp -- 200 F to 200 F, 1 hour, 30 minute hold;
>> 500 degrees per hour to 2000 F, no hold
>> 150 degrees per hour to 2210 F, 20 minute hold,
>> 150 degrees per hour DOWN to 1500 F, 30 minute hold
>>
>> Unvented kiln, plugs inserted at 1800 on the way up and
>> removed after kiln drops below 800 on way down.
>>
>> This is a 'hard' cone 6 ramp, a 6 cone will be tip
>> touching, a 7 cone will be starting to show a curve.
>>
>> Clay: Tested with Seattle Pottery Supply Sea Mix 5 and
>> Goldstone, and Clay Art Center Bennett. Color was muddy
>> over Goldstone, clear over Bennett and SM-5.
>>
>> Comments: Holds up well under leach testing. No visible
>> crazing under 30x magnifier with SM-5, some crazing
>> over Bennett. Not possible to see if there is crazing
>> with Goldstone.
>>
>>That's 44 lines by my count vs. the smaller number John B.
>> suggests, but maybe it's a point of departure. Comments?
>> Do people want something more, something else, or
>> somewhat less?
>>
>> -- Steve Slatin
>
>Ron Roy
>RR#4
>15084 Little Lake Road
>Brighton, Ontario
>Canada
>K0K 1H0
>Phone: 613-475-9544
>Fax: 613-475-3513
--
David Hewitt
Web:- http://www.dhpot.demon.co.uk
Lee Love on sun 26 feb 06
On Sat, 25 Feb 2006 06:59:20 -0800, Sam Hoffman wrote:
> I'm happy to help on the cone 10 and the cone 1 front, both
>oxidation and reduction. I think the work that has been done on
>glaze calc and testing in the past 10 years is absolutely
>astounding.
I think it really started before this Sam. The workshops I attended
at Northern Clay Center on glaze theory were with Pete Pinell and John
Reeve. What they shared was indespensible to me.
> That being said, I think Lee Love is right on with his impressions
>of historical glaze formulation. No refined materials, no glaze calc
>programs, no oxyprobes, amazing glazes. Formulation and calculation
>can take us so far; nothing like firing a kiln load of pots to see
>what you REALLY have.
I don't think the methods need to be at odds with each other. There
really are different approaches to glazes that work better with different
materials and different kinds of work you are trying to do. Some focus on
control. Others on experimentaiton and discovery. All you need to
figure, is what tool best fits the effect you want to get.
Phil Roger's book on ash glazes is pretty helpful starting point for
dealing with unrefined materials. Maybe something that continues this work
should be done.
--
Lee Love
in Mashiko, Japan http://mashiko.org
http://seisokuro.blogspot.com/ My Photo Logs
http://ikiru.blogspot.com/ Zen and Craft
"We are such stuff / As dreams are made on, and our little life / Is
rounded with a sleep."
--PROSPERO Tempest Shakespeare
June Perry on sun 26 feb 06
Count me in one helping with glaze calculation. It would also be
enlightening to have more than one program involved to see the differences in the
results.
These programs are only as accurate as the raw materials formula in the
program matching the raw materials of the user; but it certainly is of some help.
I've been designing some new clay bodies and just got the typical analysis
sheet from my supplier and one of the ball clays and it is quite a way off from
the formula in my Insight program. Now I have to figure out how to put this
latest analysis in the program!
Warm regards,
June
Hank Murrow on sun 26 feb 06
On Feb 26, 2006, at 12:00 AM, Lee Love wrote:
> On Sat, 25 Feb 2006 06:59:20 -0800, Sam Hoffman
> wrote:
>
>> That being said, I think Lee Love is right on with his
>> impressions
>> of historical glaze formulation. No refined materials, no glaze calc
>> programs, no oxyprobes, amazing glazes. Formulation and calculation
>> can take us so far; nothing like firing a kiln load of pots to see
>> what you REALLY have.
>
> I don't think the methods need to be at odds with each other.
> There
> really are different approaches to glazes that work better with
> different
> materials and different kinds of work you are trying to do. Some
> focus on
> control. Others on experimentaiton and discovery. All you need to
> figure, is what tool best fits the effect you want to get.
And Hank replies to both;
As one who prospects around the NW for 'wild' materials, I can't
emphasize enough the value of Ian Currie's Grid approach to discovering
how these wild materials can be used. No analysis is needed........ the
grid system puts your unanalyzed materials in relation to varying
alumina and silica content in 35 stages so you can easily find the
melts and discover their qualities. And you have a reference tile which
is easily stored on a shelf for further ruminations as questions come
up. It has proven extremely useful for my work with materials 'from the
landscape'. Ian's "Revealing Glazes" is a great place to start, and can
be in your hands in a week from
Cheers, Hank
www.murrow.biz/hank
Bonnie Staffel on sun 26 feb 06
One of the big problems that I run into when reading about glaze recipes
from others is the use of materials with specific names with no mention =
of
where these materials can be purchased. I imagine they are regional but
then what would be a good substitution. My practice is to test with my
known materials to see what results with my own firing schedules. I =
tried a
slow cool down this past year and really ruined the whole kiln load. =
The
glaze was OK, but my decorations that involved Albany Slip and Rutile =
ran
and destroyed the painting. So I have to go by the rule, that if it =
ain't
broke, don't fix it. =20
I am having some trouble lately with my Albany Slip brown. It is =
running
too much at Cone 9. I had mixed up a new batch and this happened. Now =
I
would like it to spread just a little, so have been testing by adding =
more
Kaolin. But that takes away the intensity of the color somewhat. Is =
there
another stabilizer that might work that anyone might suggest?
Thanks, Bonnie Staffel=20
http://webpages.charter.net/bstaffel/
DVD Throwing with Coils and Slabs
DVD Beginning Processes
Charter Member Potters Council
earlk on sun 26 feb 06
On Sun, 2006-02-26 at 14:22 -0500, June Perry wrote:
> I'd be prone to try adding a bit of high bearing fireclay like Newman
> red.
> It will add some more iron and that might help retain the color you
> want.
> You can adjust it for more or less color by adding more or lessening
> it and
> adding some lower iron bearing clay.
If you were a master baker, and so was I,
and I asked you about a particular bread
you had made, you might respond with "I
used a biga preferment, 80% unbleached
flour and 20% whole wheat. I retarded the
preferment overnight in the refrigerator.".
>From that description I would know much
about how to duplicate your loaf of bread.
If you and I were only intermediate bakers
and I asked you about a particular bread
you had made, you might respond with "I
made a very moist dough with flour and a
little yeast. After it had risen for several
hours I put it in the fridge overnight. The
next day I added 6 cups unbleached flour,
2 cups whole wheat flour, and 2 cups water,
kneaded, shaped into loaves and let rise
for 3 hours. I then baked in a 425 F oven
for 30 minutes.
If I were a novice baker I would need a
couple of typed pages of ingredients and
instructions in order to make a loaf of
rustic bread.
If I had never baked before and wanted to
duplicate your bread then I better have a
whole book to study.
Are potters any different than bakers?
I don't think so. We come in all levels of
experience and knowledge, from the
neophyte to the master. When we
communicate with each other we naturally
adjust our language, adding or deleting
detail until we are efficiently communicating
our thoughts. This is much more difficult
when using the written language as we do
on clayart.
In other words, I don't think there needs to
be any "standard" for posting recipies,
except to ensure we convey our meanings
to the intended audience.
earlk...
bothell, wa, usa
Ron Roy on mon 27 feb 06
Hi Sam,
I do work on glazes which incorporate found materials - and use a technique
that does not require an analysis of the material -
Say you have a glaze with 30% ash - the rest is made up of materials you do
have an analysis for.
So you can work with the materials that constitute 70% of the glaze. This
means you can raise or lower expansion, increase or decrease melt -
optimize for certain colours - as long as you wind up with 70% - then you
add the ash back in.
If you are doing imperical blending using such techniques improves your
chances of success dramatically.
It works -
RR
>Hi Ron & All-
>
> I'm happy to help on the cone 10 and the cone 1 front, both
>oxidation and reduction. I think the work that has been done on
>glaze calc and testing in the past 10 years is absolutely
>astounding. Authors like yourself and Frogpond John, Ian Currie,
>John Britt, Robin Hopper, etc. have been exceedingly generous in
>explaining your methods. Combining some of these new texts with the
>old classics (Rhodes, Tichane, Leach, Cardew) really gives a lot to
>work with. Computers have certainly advanced our field.
> That being said, I think Lee Love is right on with his impressions
>of historical glaze formulation. No refined materials, no glaze calc
>programs, no oxyprobes, amazing glazes. Formulation and calculation
>can take us so far; nothing like firing a kiln load of pots to see
>what you REALLY have. Thanks to Mel for driving this point home. It
>really takes the same time to fill a kiln with cups as it does to
>fill a kiln with test tiles.
> Anyway, cooperation is what really drives our field forward; this
>list really facilitates this kind of dialog.
>
>Peace,
>
> Sam
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Steve Slatin on mon 27 feb 06
David --
You are right, of course, about the problem of
materials analysis. I believe I'm typical in
this way -- I don't have any means of doing
proper (quantitative/qualitative) analysis of
materials and rely on published figures.
Some things are very consistent -- silica,
for example; others a bit less so but
don't vary so very much (calcium carb and the
like) and some materials give wildly different
results (OM#4, Gerstly Borate). I happen to
use the analyses that came with my calc
program, and supplement with published
info, but there's no way of telling if
these are more accurate than any other set.
I really don't have a solution for the
problem, but in the same way that some
standards are better than no standards,
a moderately accurate analysis is better
than no analysis. And, as long as we
give source materials as well as analysis,
we have some shot at understanding
roughly what we are dealing with and
how to duplicate it.
Wiser heads than mine are working on the
COE issue (I had written something about the
same issue you raised, but I don't recollect
if it was on or off list) and may have a
suggestion soon.
-- Steve Slatin
--- David Hewitt
wrote:
> Ron and Steve,
>
> I am always happy to convert recipes to formula
> if anyone asks, but I
> would always give a proviso that the answer is
> based on the analyses of
> the raw materials that I use in my glaze
> program. For example the
> analysis of the recipe that Steve gives below
> comes out slightly
> differently for me:-
Steve Slatin --
In watermelon sugar the deeds were done and done again
as my life is done in watermelon sugar.
__________________________________________________
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Lee Love on mon 27 feb 06
On Sun, 26 Feb 2006 13:20:59 -0800, earlk wrote:
>In other words, I don't think there needs to
>be any "standard" for posting recipies,
>except to ensure we convey our meanings
>to the intended audience.
I agree Earl. Another aspect, is that we all need different levels of
control or order. For example, my wife Jean never goes to the bush stop
without first looking at the schedual. I am the type of person, that takes
a book to the bus stop and I wait for the next bus. Jean always wants to
map out any car trip. I just want to know which way I should point the car.
Jean is always trying to "organize me." For example: the plastic
filing folders she gave me to organize my paper clutter compounds the
problem, because now I have a cutter of papers and a clutter of empty
plastic filing folders on top of them. :^)
--
Lee Love
in Mashiko, Japan http://mashiko.org
http://seisokuro.blogspot.com/ My Photo Logs
http://ikiru.blogspot.com/ Zen and Craft
"We are such stuff / As dreams are made on, and our little life / Is
rounded with a sleep."
--PROSPERO Tempest Shakespeare
Lee Love on mon 27 feb 06
On Mon, 27 Feb 2006 01:38:17 -0500, Ron Roy wrote:
>Say you have a glaze with 30% ash - the rest is made up of materials you do
>have an analysis for.
This only works if you are using refined materials. As in my example,
where I thought the wood ash was the variable, I still got the unpredictable
results using synthetic ash. This means I know that either my ball clay or
my Amakusa stone is different. I am using a new bag of ball clay, so it
must be the unrefined ball clay.
I have realized that the analysis I have for most of these potter
specific materials are not reliable.
--
Lee Love
in Mashiko, Japan http://mashiko.org
http://seisokuro.blogspot.com/ My Photo Logs
http://ikiru.blogspot.com/ Zen and Craft
"We are such stuff / As dreams are made on, and our little life / Is
rounded with a sleep."
--PROSPERO Tempest Shakespeare
Lee Love on mon 27 feb 06
On Sun, 26 Feb 2006 06:55:26 -0800, Hank Murrow wrote:
>
>As one who prospects around the NW for 'wild' materials, I can't
>emphasize enough the value of Ian Currie's Grid approach to discovering
>how these wild materials can be used.
My materials aren't exactly "wild", but they, for the most part, are not
refined. Got a second set of test tiles from Genveive's last firing, and
the point out the same as my other tests: that the change in my nami jiro
glaze was probably not from the new wood ash, but rather, from the new batch
of ball clay. I figured this out by using a synthetic wood ash
substitute. As I recall, this ball clay came from Akechi, while my
previous ball clay came from the Cooperative.
> Ian's "Revealing Glazes" is a great place to start, and can
>be in your hands in a week from
It will be the next book I buy.
--
Lee Love
in Mashiko, Japan http://mashiko.org
http://seisokuro.blogspot.com/ My Photo Logs
Susan Giddings on tue 28 feb 06
Ron Roy wrote:
>Who amoung us would be available to help? I would be for one.
>
>
>
I would be happy to help. I have Insight as well as Glazemaster.
I am not a "glaze guru" still have a great deal to learn,
but I do know how to use both these applications
and I understand how to get the analysis and seger formula.
Susan
Ron Roy on tue 28 feb 06
Hi Bonnie,
Send me the recipe and I'll make some suggestions - I assume you want to
fix that batch so just want to add materials - right?
Tell me what you have added as well.
RR
>One of the big problems that I run into when reading about glaze recipes
>from others is the use of materials with specific names with no mention of
>where these materials can be purchased. I imagine they are regional but
>then what would be a good substitution. My practice is to test with my
>known materials to see what results with my own firing schedules. I tried a
>slow cool down this past year and really ruined the whole kiln load. The
>glaze was OK, but my decorations that involved Albany Slip and Rutile ran
>and destroyed the painting. So I have to go by the rule, that if it ain't
>broke, don't fix it.
>
>I am having some trouble lately with my Albany Slip brown. It is running
>too much at Cone 9. I had mixed up a new batch and this happened. Now I
>would like it to spread just a little, so have been testing by adding more
>Kaolin. But that takes away the intensity of the color somewhat. Is there
>another stabilizer that might work that anyone might suggest?
>
>Thanks, Bonnie Staffel
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Ron Roy on thu 2 mar 06
Hi Lee,
Not necessarily so - some raw materials are quite steady - Hawthorn fire
clay is a good example.
If you keep records and do regular testing you will eventually be better
able to cope with variable materials. It certainly works with the semi
refined materials. Even if you find out which materials you are you are
using are more variable it will help.
RR
>>Say you have a glaze with 30% ash - the rest is made up of materials you do
>>have an analysis for.
>
>This only works if you are using refined materials. As in my example,
>where I thought the wood ash was the variable, I still got the unpredictable
>results using synthetic ash. This means I know that either my ball clay or
>my Amakusa stone is different. I am using a new bag of ball clay, so it
>must be the unrefined ball clay.
>
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Ron Roy on thu 2 mar 06
Hi Steve,
I had to ask John about this so that is why I am late.
I see there are a few willing to do this - can I leave this to you to
orgainize - I will help of course if necessary.
I suggest someone take the expansion data in chapter five for the 5 fit
glazes ( I have no brain for arithmatic) and make an approximate table that
lists the the comparitive numbers of comparitive expansions we have
included.
349 = 6.4 = 64.8 - measured = 5.4
425 = 7.0 = 71.0 - measured = 5.78
Using the 2nd number 6.4 the next one would be 6.5, then 6.6 etc.
I can easily make some glazes that are closer to 350 and 425 if necessary -
and Glaze Master software will cycle through the three sets we have used in
the book so when you have one you have them all.
If the numbers are filled in between all five glazes then when the
expansion of a glaze is calculated it will be a simple a mater of
including all three - or 4
The list can be available to all.
I'll be happy to provide some general comments and would hope others like
David Hewitt who have such deep understanding of this aspect would do so
as
well.
Lets talk about this at NCECA and iron out the details.
Steve said:
>I can do several a day if need be; once we settle on a template
>it shouldn't take too long. Or I can just do the calc for a
>potter who wants to do the rest and just needs the Seger,
>COE, and so on.
>
> I see Sam H. has already offered to help as well; Lee
> L has raised a question about recipes that aren't standardized
> to begin with and while I can see a simple way to get there
> for people who use his method (wet measure) and who
> start with refined materials, I can't think of what to do with
> a material of unknown constituents (i.e. 'clay from the hole
> where the apple tree used to be') but I'd suggest we can
> start with what we know and fill in blanks as we go along.
>
> I do think we should consider which measure of COE we
> collectively are most comfortable with, and so on. As for
> comments others have made about specificity (that is,
> what to do if the glaze recipe calls for 'spar' and doesn't
> specify which one) I'd prefer that we only publish glaze
> recipes that have actually been made, and we can just
> fill in whatever class of material we actually used.
>
> Last note -- if we start to do this, less than fully successful
> recipes could also be posted, as they add to the information
> base. (The 'tarnished yellow' I posted wasn't interesting
> enough to pursue further for me, but it vitrified well, and
> stood up to the lemon juice test.)
>
> I don't know how many people are out there who'd want
> to contribute a recipe but who can't do the calculations,
> but I'd suspect it's not that great a number. It might only
> take a few folks to get the thing working.
>
> Best wishes -- Steve S
>
>Ron Roy wrote:
> Hi Steve - I like it - that should be enough for most glazes - what we also
>need is a list of potters on clay art who would be willing to help anyone
>wishing to post a glaze - to fill in any missing information.
>
>Many are willing to share but don't use a calculation program so would not
>be able to fill in the Seger formula, expansion, ratio for instance.
>
>Who amoung us would be available to help? I would be for one
>
>Steve Slatin --
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Kathy Forer on sat 4 mar 06
On Feb 23, 2006, at 1:09 PM, Kathy Forer wrote:
> On Feb 22, 2006, at 10:51 PM, Jim Brooks wrote:
>> Posting a glaze recipe on the internet --to an indivudual --does
>> not
>> violate copyright laws....unless it generates income or become a
>> commercial venture.
>
> The last part of this statement is wrong and the first part about
> open availability has questionable repercussions.
Belated apologies, Jim Brooks, for my harsh response to your message.
I had originally misread your statement as supporting unauthorized
copies and wrote a bit of a diatribe, then when I proofed and saw you
were saying "may not," "nor" and ONLY rather than "may," well I just
changed some words around but unfortunately much of the tone remained.
As for recipes and copyrights, both Steve's post regarding need for
more information in recipes and Alisa's comments about freedom from
standardization of formatting seem right on to me. And perhaps a
recipe is more of a concept manifested anew each time than a
particular [copyrightable] instance of a work that can be said to be
its sole expression.
Lots to learn!
Kathy
Kathy Forer
www.foreverink.com
Lee Love on sun 5 mar 06
On Feb 23, 2006, at 1:09 PM, Kathy Forer wrote:
> On Feb 22, 2006, at 10:51 PM, Jim Brooks wrote:
>> Posting a glaze recipe on the internet --to an indivudual --does
>> not violate copyright laws....unless it generates income or become a
>> commercial venture.
Actually, you CAN make money publishing other people's recipes. Under the
copyright law, recipes are not copyrightable. Only instructions
accompanying the recipe are copyrightable, if they are unique methods.
You can find the information about recipes and copyrights on the web
or by searching ClayArt archives. (For those who are new here or just
sleep typing. ;^) )
--
Lee in Mashiko, Japan
http://mashiko.org
May Luk on sun 5 mar 06
Hiya Kathy;
I just went to an informal lecture about plagiarism,
and then I read this in the Saturday paper. It
comments on the Dan Brown lawsuit. Good arguement
here:
http://books.guardian.co.uk/danbrown/story/0,,1722872,00.html
Here's a link about intellectual property (UK). Design
oriented, but very informative and a lot of the info
is applicable to other countries.
http://www.designcouncil.org.uk/
Design Council > Home > About Design > The Design
Process > Intellectual Property
When it comes to copyright, it really just boils down
to:
1- Are you being copied?
2- Do you want to copy?
We think differently depends on our position (No.1 or
No.2)
Another one of my unsolicited opinion. :-P
Regards
May
London, UK
P.S. Since there's no money* in pottery for most of
us, I am going for intellectual integrity. It sounds
good in my world.
* In some postcodes, there's plenty of money for
ceramics. I went to COLLECT at the V&A last month.
Most of the 3 digit price tagged pots (low end for
this venue) were sold in the first morning. You could
smell ££££ in the air - very exciting.
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
As for recipes and copyrights, both Steve's post
regarding need for
more information in recipes and Alisa's comments about
freedom from
standardization of formatting seem right on to me. And
perhaps a
recipe is more of a concept manifested anew each time
than a
particular [copyrightable] instance of a work that can
be said to be
its sole expression.
Lots to learn!
Kathy
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