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commercial cone 6 glazes

updated thu 14 sep 06

 

Shirley Ostrander on tue 12 sep 06


Hey folks! I needed to vent a little and ask some questions.



I purchased some commercial cone 6 glazes from L & R specialties in Nixa, MO
- www.claydogs.com - and I've had them for a few
months. Let me say that I am VERY new to all of this - I took my first
throwing class in January 06 and can't keep my hands out of the "mud" !!!



I've only done earthenware and have been very successful with marbling white
and red earthenware clays. I wanted to try my hand at stoneware and
porcelain and I've been pleased with the results. I've done some marbling
with the porcelain and well - I'm hooked.



The one thing that I HATE (because I'm no good at it) is glazing. The
marbled earthenware gets a simple clear dipping glaze that is premixed and
so very simple! I thought - hey - you can get dipping glazes for stoneware
and porcelain, I'll try that. My very first glaze firing at cone 6 was a
huge disappointment! While there is a lot of information out there about
mixing one's own glazes and tweaking formulas, there's very little (at least
that I've found) on the mechanics of adding water and testing the
consistency and running the glaze through a sieve, how long to dip, how
thick the coat of glaze should be, etc. Shoot, even the class I took only
taught throwing - not glaze application, not firing, nothing else. is that
typical? If so - it's time that someone fix that problem.



I have a copy of Mastering cone 6 glazes - but as far as I've gotten into
it, it focuses on building a good recipie - not on the "stir until peaks are
shiny and stiff" part of the process.



Having said all that - here's what happened. I mixed 2 glazes - the clear
and the pattern blue. I used distilled water and 5 lbs of dry glaze. I put
less than a gallon of water with the dry glaze, even though someone at L&R
told me that a gallon would be fine and that a hydrometer wouldn't really be
necessary. It was thinner than egg nog, heaver than milk - "light cream"
and coated my fingers. I dipped and the coating was similar to what I get
on the earthenware that been dipping in the clear glaze (the consistency was
similar too) The clay bodies that I used were L&R ^6 porcelain and ^6
stoneware. I thought, hey that should be a good match, right? I called
them today because the "pattern blue" that I used turned out BLACK - on both
the porcelain and the stoneware - turns out that someone forgot to put the
rutile in a batch that went out (go figure, I'd get 5 of the 25 or so pounds
that slipped by). The clear - well, it crazed - BADLY and is still crazing.
(it might have settled by now) turns out that "oh yeah, the clear does
that".. Now, L&R is sending me replacement pattern blue - but DAMN - what's
with the clear crazing - don't you think they should mention that when they
sell it - or in the description somewhere?



Got any ideas where I can get some commercial glazes that will work
reasonably well? I'm not ready to get into mixing my own - I need to really
focus on the clay and the forms and the process - I will expand eventually,
but for now - I'd like to at least have something that I can count on to
work consistently. I'm doing this for pleasure - not for a living so until
I retire from my 'day job', I'm not committing to mixing my own clay bodies
and glazes.



Oh yeah - I have a brand new evenheat electric kiln with computer controller
and it's been fired to ^04, and ^06 less than 10 times and to ^6 once. in
case that makes a difference.



Any thoughts/advice is welcome!



Shirley

In Memphis where it's cooled down considerably and I'm still at work
(11:08pm) trying to get home before midnight. :-)

Mike Juengling on wed 13 sep 06


Hi Shirley, I am just a clay 'weekend warrior' so take my advice for
what it is worth. I had a similar experience when I first started a few
years ago. A local pottery supplier talked me into buying their
prepared glazes. I told them how I was using it and firing it (^6
oxidation) and they showed me samples and told me how easy it was going
to make my life. Well after firing a batch I had the same disappointing
results as you, except mine was caused by blistering and running. Not
knowing their formula I couldn't adjust their glazes to fix the
problems. I ended up pitching all the commercial glaze out.

I went back to mixing and testing my own. This has led me to a lot of
reading about glaze development and testing glazes (which, because of my
part time involvement is an on going process). I have had some good
results and some bad, but I am beginning to learn how to control the
process. It is a whole lot more satisfying, when it comes out right if
I am responsible for the whole process.

Anyways, I guess what I am trying to recommend is that you should
reconsider 'rolling your own' glaze. It is the best way to get what you
want.

Michael Juengling

dwichman@frontiernet.net on wed 13 sep 06


I feel your pain..... Pottery is really a mixture of science, skill,
and art. You spend hours and hours (happily, of course) learning the
way clay and your hands respond to each other, and when you begin to
get the clay to cooperate, you realize there is so much more to learn
in getting control of glazing. Even in using commercial glazes, the
difference in the fired look of the glaze from clay to clay, thick to
thin, etc. is amazing. Then you decide to paint some glaze over what
you are using and can get beauty or the beast, or at worst, ruined kiln
shelves.

I also, feel that I am not at the point where I can make my own glazes,
though I hope to someday. In the meantime, I have found that some of
the Laguna Glazes are quite reliable and somewhat flexible as far as
working on several clays and I can order them in dry form from Davens
Ceramic Center in Atlanta. I also use some Opulance glazes from Mid
South Ceramics in Nashville and have had good luck with them on almost
any clay, though they are a bit more expensive.

By the way, I also really disliked glazing for a long time. It takes
as much practice to learn to glaze something in the best practical way
as it does to make a good pot. Once you've done it as many times as
you have made a pot, it gets easier and you get to appreciate and enjoy
it as part of the process....(at least this has been my experience...)

Debi Wichman
Cookeville, TN
http://www.elementterra.com

Lynn Goodman Porcelain Pottery on wed 13 sep 06


Shirley,

It sounds like you are doing everything right. Here are some things to
keep in mind:

1) No one ^6 glaze will fit all ^6 clay bodies. ^6 porcelain is
notorious for crazing glazes. Although, I certainly would think that a
clay manufacturer's own glazes should fit. I think your best bet is to
try several brands of glazes to see what fits best, since the company
you're dealing with can't help you. Buy small amounts and test, test,
test.
2) Like anything else in clay work, glazing properly takes practice.
Nobody is good at it right away.
3) Ask your teacher to show you how to mix up glaze and what you should
be looking for. If your teacher won't help you, see if you can find
another teacher or someone who has been working in clay for a while who
will help you.

Good luck! If you stick with it, the glazing should improve.

Lynn


On Sep 13, 2006, at 12:08 AM, Shirley Ostrander wrote:

>
> Having said all that - here's what happened. I mixed 2 glazes - the
> clear
> and the pattern blue. I used distilled water and 5 lbs of dry glaze.
> I put
> less than a gallon of water with the dry glaze, even though someone at
> L&R
> told me that a gallon would be fine and that a hydrometer wouldn't
> really be
> necessary. It was thinner than egg nog, heaver than milk - "light
> cream"
> and coated my fingers. I dipped and the coating was similar to what I
> get
> on the earthenware that been dipping in the clear glaze (the
> consistency was
> similar too) The clay bodies that I used were L&R ^6 porcelain and ^6
> stoneware. I thought, hey that should be a good match, right? I
> called
> them today because the "pattern blue" that I used turned out BLACK -
> on both
> the porcelain and the stoneware - turns out that someone forgot to put
> the
> rutile in a batch that went out (go figure, I'd get 5 of the 25 or so
> pounds
> that slipped by). The clear - well, it crazed - BADLY and is still
> crazing.
> (it might have settled by now) turns out that "oh yeah, the clear does
> that".. Now, L&R is sending me replacement pattern blue - but DAMN -
> what's
> with the clear crazing - don't you think they should mention that when
> they
> sell it - or in the description somewhere?


Lynn Goodman
Fine Porcelain Pottery
Cell 347-526-9805
www.lynngoodmanporcelain.com