John Post on mon 13 aug 07
I bet a significant number of K-12 programs would be better off if they
got off low-fire talc bodies altogether. Just quit cold turkey and
switch to terracotta. A terracotta body fired to cone 1 with a majolica
glaze can get great color just by using the same lowfire glazes right
over the white glaze before it is fired. I have kindergarten students
make majolica flower tiles. They make a flower tile, we bisque it, wax
the bottom and then dip it into majolica glaze and then they go from
table to table in the classroom adding lowfire glazes right over the top
before we fire it again.
I have seen far too many K-12 art teachers struggle with these lowfire
talc bodies. They warp terribly when drying and often crack especially
in pieces of uneven thickness. Terra cotta with grog does not have
these problems.
There will be less kiln meltdowns with this stuff gone. It's not so
much that the kiln terribly overfires, it's that the lowfire talc bodies
melt down and then ruin the shelves and the kiln floor. There's not
much room for error with these bodies.
Many K-12 art teachers don't monitor their kiln much when it is firing.
They rely on the sitter to shut it off. When that fails they either
have to let the limit timer shut it off or the kiln shuts itself off
when the elements break from the heat.
The terra cotta I work with (Rovin's RO-82) can go to cone 6 without
even deforming.
Here are some links to majolica works done by kids who are 5-10 years old.
They used amaco lowfire glazes (cone 06) over the white majolica glazes
listed below (fired to cone 1).
Clay chickens:
http://www.macomb.k12.mi.us/utica/Schwarzkoff/art-archives/!art-06-07/clay%20chickens/clay-chickens.htm
Clay flowers:
http://www.macomb.k12.mi.us/utica/Schwarzkoff/art-archives/!art-06-07/okeefe/clay-flowers/clay-flowers.htm
Clay slump bowls:
http://www.macomb.k12.mi.us/utica/Schwarzkoff/art-archives/!art-06-07/clay-majolica-bowls/majolica-bowls.htm
To see all the art go here and click on the animated Mr. Post icon:
http://www.schwarzkoff.com/
Here are a few cone 1 white glazes I have used with the kids I teach...
Post's White #1 (Cone 1-3)
15 EPK
20 Frit 3195
60 Frit 3124
5 Flint
add
15 superpax
Post's White #2 (Cone 1-3)
24.5 EPK
26.6 Frit 3195
27.8 Frit 3134
5.7 Custer Spar
3.3 Whiting
12.1 Flint
add
15 superpax
Post's White #3 (Cone 1-3)
27.1 EPK
32.6 Frit 3134
20.6 Custer Spar
6.9 Whiting
12.8 Flint
add
15 superpax
John Post
Sterling Heights, Michigan
Ron Roy wrote:
>Hi Craig,
>
>Looks like it is over for Natal 100 - they now have studies that link it
>with lung disease - it will be banned in NY state schools first.
>
Joe Herbert wrote:
>What the pursuit of whiteness in clay products does for (to) us. Would not
>a red firing earthware be more plastic, cheaper to buy, and easier to fire?
>But it isn't white.
>
>Joe
>
>
A Kettner on mon 13 aug 07
Not all talc is the same.
Nytal 100 hr: bad
Pioneer or Texas Talc: good
Jon Pacini wrote a terrific email about this issue and the testing
that has been done at Laguna Clay. So before you start switching to
red clays because somebody else likes them better, I suggest you visit
the archives and then decide for yourself.
Arthur
On 8/13/07, John Post wrote:
> I bet a significant number of K-12 programs would be better off if they
> got off low-fire talc bodies altogether. Just quit cold turkey and
> switch to terracotta. A terracotta body fired to cone 1 with a majolica
> glaze can get great color just by using the same lowfire glazes right
> over the white glaze before it is fired. I have kindergarten students
> make majolica flower tiles. They make a flower tile, we bisque it, wax
> the bottom and then dip it into majolica glaze and then they go from
> table to table in the classroom adding lowfire glazes right over the top
> before we fire it again.
>
> I have seen far too many K-12 art teachers struggle with these lowfire
> talc bodies. They warp terribly when drying and often crack especially
> in pieces of uneven thickness. Terra cotta with grog does not have
> these problems.
> There will be less kiln meltdowns with this stuff gone. It's not so
> much that the kiln terribly overfires, it's that the lowfire talc bodies
> melt down and then ruin the shelves and the kiln floor. There's not
> much room for error with these bodies.
> Many K-12 art teachers don't monitor their kiln much when it is firing.
> They rely on the sitter to shut it off. When that fails they either
> have to let the limit timer shut it off or the kiln shuts itself off
> when the elements break from the heat.
> The terra cotta I work with (Rovin's RO-82) can go to cone 6 without
> even deforming.
>
> Here are some links to majolica works done by kids who are 5-10 years old.
> They used amaco lowfire glazes (cone 06) over the white majolica glazes
> listed below (fired to cone 1).
>
> Clay chickens:
> http://www.macomb.k12.mi.us/utica/Schwarzkoff/art-archives/!art-06-07/clay%20chickens/clay-chickens.htm
> Clay flowers:
> http://www.macomb.k12.mi.us/utica/Schwarzkoff/art-archives/!art-06-07/okeefe/clay-flowers/clay-flowers.htm
> Clay slump bowls:
> http://www.macomb.k12.mi.us/utica/Schwarzkoff/art-archives/!art-06-07/clay-majolica-bowls/majolica-bowls.htm
>
> To see all the art go here and click on the animated Mr. Post icon:
> http://www.schwarzkoff.com/
>
> Here are a few cone 1 white glazes I have used with the kids I teach...
>
> Post's White #1 (Cone 1-3)
> 15 EPK
> 20 Frit 3195
> 60 Frit 3124
> 5 Flint
> add
> 15 superpax
>
> Post's White #2 (Cone 1-3)
> 24.5 EPK
> 26.6 Frit 3195
> 27.8 Frit 3134
> 5.7 Custer Spar
> 3.3 Whiting
> 12.1 Flint
> add
> 15 superpax
>
> Post's White #3 (Cone 1-3)
> 27.1 EPK
> 32.6 Frit 3134
> 20.6 Custer Spar
> 6.9 Whiting
> 12.8 Flint
> add
> 15 superpax
>
> John Post
> Sterling Heights, Michigan
>
>
> Ron Roy wrote:
>
> >Hi Craig,
> >
> >Looks like it is over for Natal 100 - they now have studies that link it
> >with lung disease - it will be banned in NY state schools first.
> >
>
> Joe Herbert wrote:
>
> >What the pursuit of whiteness in clay products does for (to) us. Would not
> >a red firing earthware be more plastic, cheaper to buy, and easier to fire?
> >But it isn't white.
> >
> >Joe
> >
> >
>
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