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base glaze

updated wed 4 jan 12

 

gracie on sun 29 nov 98

Hello, everyone.....I'm new to CLAYART but have been potting many years..
Up until now, I've been content with glazes that stay right where I want
them on the pot.. I fire electric^6, & with the exception of Floating Blue,
most of the glazes are very reliable.. However, I wonder if someone would
be willing to share a base glaze that I could use in combination with
oxides.. the base glazes I've tried don't allow the oxides to do their
thing... ie: run or blend with other oxides ... Thanks for any
considerations... I'll be sharing info as well.. gracie

Michelle Henderson on tue 16 feb 99

Hi all Clay nuts...
Im just starting out, so forgive the elementary question...I am looking
to start mixing my own glazes and was given a recipe for ^5-6 oxidation and
would like some opinions/suggestions on it and possibly get other base glaze
formulations.....
Nepheline Syenite 47.3
Colemanite 27.0
Flint 20.3
Kaolin (EPK) 5.4
Bentonite 2
for colors use
Green-4% Copper Carbonate
Brown-5% Iron Oxide, 5% Tin Oxide
Turquoise-5% Tin Oxide, 2% Copper Carbonate
White-6% Tin Oxide
Blue-1/4% Cobalt Oxide, 5% Tin Oxide
Creamy Yellow-5% Tin Oxide, 5% Vanadium Pentoxide
Olive Green-5% Tin Oxide, 3% Vanadium Pentoxide, 3% Copper Carbonate

Thanks in advance...
Michelle H.

Barney Adams on wed 17 feb 99

Hi,
Others will probably answer this too. I just had Ron's workshop and
it's good exercise for me. If you get a chance to take one of Ron Roy's
workshops jump at it. Glaze anaysis is'nt all that difficult if you listen to
Ron has to say.

This glaze is way under supplied in silica and the expansion would be
pretty high for stoneware. I'll give you some base glazes to start with,
but understand they are not tested. You need to do the testing!
I like to have a lot of secondary fluxes.

Untitled Recipe 1
Expansion is 7.00 (I've been following Tom Buck's advise on this value
for stoneware and it's been good for me.

Al:Si is 13.79 I would think this would be gloss.
=================
CUSTER FELDSPAR..... 15.00 15.00%
FRIT 3134........... 31.00 31.00%
SPODUMENE........... 10.00 10.00%
NYTAL TALC.......... 3.00 3.00%
STRONTIUM CARBONATE. 8.00 8.00%
Flint............... 27.00 27.00%
EPK KAOLIN.......... 6.00 6.00%
========
100.00

CaO 0.32* 7.84%
Li2O 0.06* 0.80%
MgO 0.05* 0.95%
K2O 0.04* 1.65%
Na2O 0.14* 3.85%
SrO 0.13* 5.88%
TiO2 0.00 0.02%
Al2O3 0.18 7.83%
B2O3 0.25* 7.50%
P2O5 0.00 0.01%
SiO2 2.44 63.60%

Base Satin 0001 I'm not as happy with this for satin
Expansion 6.97 I'd like to adjust this to 7.00
Al:Si 7.99 Since testing and experience is what I lack
the most I'm not sure if this will be satin
================
CUSTER FELDSPAR..... 17.00 17.00%
FRIT 3134........... 30.00 30.00%
SPODUMENE........... 13.00 13.00%
NYTAL TALC.......... 8.00 8.00%
STRONTIUM CARBONATE. 5.00 5.00%
Flint............... 12.00 12.00%
EPK KAOLIN.......... 15.00 15.00%
========
100.00

CaO 0.30* 7.56%
Li2O 0.08* 1.04%
MgO 0.14* 2.53%
K2O 0.04* 1.90%
Na2O 0.14* 3.84%
SrO 0.08* 3.68%
TiO2 0.00 0.06%
Al2O3 0.27 12.60%
B2O3 0.23* 7.26%
P2O5 0.00 0.04%
SiO2 2.17 59.31%

Base Matt 0001 I'm guessing that this would be matt as I remember
the large amount of CaO will help along with the
MgO
and the Zinc. If I have this wrong somebody please
get me
back on track.

Expansion 6.99
Al:Si 6.62
=================
.................... 35.00 35.00%
WOLLASTONITE........ 24.00 24.00%
NYTAL TALC.......... 7.00 7.00%
ZINC OXIDE.......... 1.00 1.00%
SPODUMENE........... 20.00 20.00%
EPK KAOLIN.......... 11.00 11.00%
FLINT............... 2.00 2.00%
========
100.00

CaO 0.22 12.67%
Li2O 0.05 1.56%
MgO 0.05 2.16%
K2O 0.04 3.74%
Na2O 0.02 1.14%
ZnO 0.01 1.02%
TiO2 0.00 0.04%
Al2O3 0.15 15.81%
P2O5 0.00 0.03%
SiO2 1.00 61.67%
Fe2O3 0.00 0.16%
I tried to keep to the same bunch of materials for all three.
Again no silver bullet when it comes to glazes. I just whipped these
up and have not tested them. The testing is where I need to go back in
and re-evaluate after seeing Ron. I'm probably going to be buying some
soft fire brick and making a mess of tiles. There are issues with these
as base glazes depending on the colors you want. If you dont have the Hamer
Dictionary you should get it.

Hope this gets you to reading it's slightly (but only slightly) more than having
a recipe for a base glaze. Good luck.

Barney



Michelle Henderson wrote:

> ----------------------------Original message----------------------------
> Hi all Clay nuts...
> Im just starting out, so forgive the elementary question...I am looking
> to start mixing my own glazes and was given a recipe for ^5-6 oxidation and
> would like some opinions/suggestions on it and possibly get other base glaze
> formulations.....
> Nepheline Syenite 47.3
> Colemanite 27.0
> Flint 20.3
> Kaolin (EPK) 5.4
> Bentonite 2
> for colors use
> Green-4% Copper Carbonate
> Brown-5% Iron Oxide, 5% Tin Oxide
> Turquoise-5% Tin Oxide, 2% Copper Carbonate
> White-6% Tin Oxide
> Blue-1/4% Cobalt Oxide, 5% Tin Oxide
> Creamy Yellow-5% Tin Oxide, 5% Vanadium Pentoxide
> Olive Green-5% Tin Oxide, 3% Vanadium Pentoxide, 3% Copper Carbonate
>
> Thanks in advance...
> Michelle H.

Chris Schafale on wed 17 feb 99

Hi Michelle,

From one near-beginner, some thoughts.

1. This is the base glaze for the famous or infamous Floating Blue,
which you will be hearing about if you haven't already. Colorants
for it are 4 rutile, 2 red iron oxide, and 1 cobalt. Fires to cone 5
or to cone 6 if you fire fast. If you fire slower or hotter, it will
be unattractively greenish. If the glaze coat is too thin, it will
be brown. If too thick, it may crawl. Otherwise, it's lovely.

2. Colemanite is no longer available, but you can sub Gerstley
Borate.

3. DO NOT use vanadium pentoxide -- it's quite toxic.

4. Tin can be kind of expensive, so you may want to experiment with
other opacifiers as well.

5. This glaze is known to craze on some claybodies and not others
in this firing range, so listen for the tell-tale "pings" right after
it comes out of the kiln.

Good luck, and happy glazing. If I can help, please let me know.

Chris

> ----------------------------Original message----------------------------
> Hi all Clay nuts...
> Im just starting out, so forgive the elementary question...I am looking
> to start mixing my own glazes and was given a recipe for ^5-6 oxidation and
> would like some opinions/suggestions on it and possibly get other base glaze
> formulations.....
> Nepheline Syenite 47.3
> Colemanite 27.0
> Flint 20.3
> Kaolin (EPK) 5.4
> Bentonite 2
> for colors use
> Green-4% Copper Carbonate
> Brown-5% Iron Oxide, 5% Tin Oxide
> Turquoise-5% Tin Oxide, 2% Copper Carbonate
> White-6% Tin Oxide
> Blue-1/4% Cobalt Oxide, 5% Tin Oxide
> Creamy Yellow-5% Tin Oxide, 5% Vanadium Pentoxide
> Olive Green-5% Tin Oxide, 3% Vanadium Pentoxide, 3% Copper Carbonate
>
> Thanks in advance...
> Michelle H.
>
>
Light One Candle Pottery
Fuquay-Varina, NC
candle@nuteknet.com

claypots on thu 18 feb 99

-------------------
Hi Michelle: You might want to substitute Zircopax, Opax, Ultrox, or one of=
the
other opacifiers for the tin since tin is dreadfully expensive.
Debra

gracie on sun 28 mar 99

Sorry,folks.. Thanks Judi for reminding me to "tell all" when I ask for
help!! I thought it would be better to use the oxides as a wash on top of
the base glaze.. i only want to use one glaze (light in color) or just
plain white...i just love the running /feather effect I have seen on other
potters pots... and they said they simply put on oxides...didn't reveal the
actual technique.. I can certainly add the oxides to a clear glaze.. no
problem there.... Thanks for any help... gracie

Jeff Seefeldt on mon 29 mar 99

would you please explain the technique again,, i didn't quite understand but it
sounds like something I'd like to try. I've only recently started mixing my own
glazes. It is so much fun mix up a batch with no real idea exactly what it will
look like.

I hope none of the neighbors have been watching thru the windows as I race
downstairs in a just a towel to open the kiln before I shower, shave or do anyth
else in the morning.


half naked and potting in western Illinois

jeff

gracie wrote:

> ----------------------------Original message----------------------------
> Sorry,folks.. Thanks Judi for reminding me to "tell all" when I ask fo
> help!! I thought it would be better to use the oxides as a wash on top of
> the base glaze.. i only want to use one glaze (light in color) or just
> plain white...i just love the running /feather effect I have seen on other
> potters pots... and they said they simply put on oxides...didn't reveal the
> actual technique.. I can certainly add the oxides to a clear glaze.. no
> problem there.... Thanks for any help... gracie

gracie on fri 2 apr 99

Hi, Judy.
While I have been reading, but not yet applying the suggestions on the
overlapping glazes... I have not gotten an actual recipe.. I only want to
use a base with oxides.. not two overlapping glazes.. if you have one.. I
would love to try it.. Thanks for any help.. and thanks to all who have
responded.. I have printed out each one and plan to try the ones I have.. a
great group, as always... gracie

mel jacobson on mon 2 jan 12


i like to think of a `base` glaze for a pottery.
something that you like, works well with your
clay and will last a long time.

sorry, but the facts are clear...it takes years to make
a glaze work for you that will give you total trust and legs
for years to come.

you can add color to many buckets of base glaze.
you know it will layer and fire just fine.

i have been to many studios where there are
dozens of buckets of all sorts of glaze.
most do not match up.
it is a lesson in futile behavior.

it means the person is looking for that `silver bullet`....
and it is the same as running to cm each month to find
out what is `cool`.

you make `cool` in your own studio, with your own
research and aesthetics.

i know i have had to change things as time passes.
i have added pete's cranberry to my `base`, and am
working on several new blues. modern aesthetics of
my customer base dictates that.

in a note from tom turner he indicates that he will no
longer fire cone 10 reduction...he is selling his kiln.
he has switched to electric crystal glazes full time.
he has found a new sales motif.
good for him. times change. and, for full timers
it means you change with it...or go broke.

but, i bet tom has been full time in the research mode to find
something that works for him.

richard aerni makes very colorful, bold ash glazes.
i bet he tweaks things all the time...but, he does not
have 60 ideas going at once. it has taken him years
to perfect what he does.

so it seems simple is best. learn it, understand it and
go with it.
mel

from: minnetonka, mn
website: http://www.visi.com/~melpots/
clayart link: http://www.visi.com/~melpots/clayart.html

Alisa Liskin Clausen on tue 3 jan 12


I can really reinforce my agreement with Mel with using a base glaze
in the studio.
One of the best experiments I ever started on after I had tested many,
many glaze recipes, was to color a base glaze.
I have a set list of 32 coloring and opacifying oxides which I use to
test in a base glaze.
Amazing what one base can yield with 32 color additives.
I took some of the colorants from favorite glazes with bad tempers
like Blue Hare (let us not begin this thread)
and added it to my bases. Sometimes I could yield the same color, in
the new base, and it would fire the same each time.

In my studio I may still have 25 buckets of glaze, but most of them
are my Dolita Base with colorants and I can overlap
from here to there with no glaze conflicts. For Ox. Cone 6, I think
Brain G's base and Tony H's 20 x 20 bases are good starts.
All on my website at Flickr.

I do have other glazes in my studio, but I tend to mix them in small
batches and use them like more like
specialty glazes (L.L. Bean glazes). I think using a base and testing
as many colorants and combinations of
colorants can give surprising and wonderful results.

Best regards from Alisa in Denmark