James Hagan on fri 2 may 97
>I believe you will find that Mullite...as sold by the Kyanite Corp in
>Dillwyn, Georgia
It's Dillwyn, Virginia and they don't have an 800 number. Telephone is
804-983-3579. 35mesh raw Kyanite is $144.50 a ton and they will sell
smaller quantities at that price if you pick it up.
I use it in my sculpture body.
jimH
James Hagan- art dept- U of Va
804-293-4524
http://faraday.clas.virginia.edu/~jgh
Gaydos, Frank on sun 5 oct 97
I,m trying to get information on a material called Kyanite. It was
recommended that I add this to my clay body (04 terracotta) to help
prevent cracking. Is this true and what percentage should I use.
The technique I use on my 22 inch platters is to reheat them gently after
the initial base coat firing and then use slip trailers to add more
glaze in a controled pattern, the heat of the platter sets the glaze
where I lay it while I'm working on it at the wheel. My grog percentage
is five pounds fine and five medium. I also add nylon fibers to help with
the extrusions of the foot and rim which I then add to hump molded clay.
Any thoughts on this would be helpful.
Frank, in sunny and warm (80) Philadelphia.
Tadeusz Westawic on tue 7 oct 97
Hi Frank,
I have just started using the kyanite in my raku body. But before I (or
hopefully someone who REALLY knows) attempt to help you, please post the
complete formula of the clay body you are currently using.
For example, my raku body is what I know as "Soldner's Raku Body", it is
by weight:
50 fireclay
30 silica sand (60 mesh)
20 talc
--
add 2% bentonite
To the above formula I have added 20% kyanite (40 mesh).
Kyanite is rough and heavy, making the shipping cost expensive. On the
wheel the body is now too open. That is, a cylinder of acceptable wall
thickness and not excessively watered will lose height by settling after
each "money pull". I have decided on bringing the fireclay percentage
back to a true 50% of the finished dry body weight to fix the unsettling
settling problem.
I have developed (am developing) a multi-fire raku technique that
involves much thermal abuse to the pots. I was having three distinct
problems:
1. cylinder vessels were cracking when I sprayed parts of the hot from
the kiln pots with a thin stream of water.
2. Anenome forms (flattened spherical forms) were developing radial
cracks from the lip outward.
3. Shallow dome type lids larger than 6 inches in diameter developed
cracks from the edge straight across the middle.
The kyanite addition seems to have solved No 1, above, nicely. No's 2
and 3 have not yet been addressed as I haven't got to them yet, but will
between now and Christmas.
Tadzu -- in all-clear, all-blue-sky SW New Mexico
Gaydos, Frank wrote:
>
> ----------------------------Original message----------------------------
> I,m trying to get information on a material called Kyanite. It was
> recommended that I add this to my clay body (04 terracotta) to help
> prevent cracking. Is this true and what percentage should I use.
> The technique I use on my 22 inch platters is to reheat them gently after
> the initial base coat firing and then use slip trailers to add more
> glaze in a controled pattern, the heat of the platter sets the glaze
> where I lay it while I'm working on it at the wheel. My grog percentage
> is five pounds fine and five medium. I also add nylon fibers to help with
> the extrusions of the foot and rim which I then add to hump molded clay.
> Any thoughts on this would be helpful.
> Frank, in sunny and warm (80) Philadelphia.
Aurore M Chabot on wed 8 oct 97
Kyanite can be substituted for all or some of your grog and it is
supposed to cut down on cracking. I have been using it in my terra
cotta tile body along with grog. Kyanite comes in fine, medium, and
coarse, just like grog and you can order it from STandard Ceramics in
Pennsylvania (I don't have the address handy). It also seems to help
cut down on warping. Might as well try it and see, especially if you're
having trouble with cracking. You also might increase your total amount
of grog/kyanite. Good luck.
Aurore Chabot
On Sun, 5 Oct 1997, Gaydos, Frank wrote:
> ----------------------------Original message----------------------------
> I,m trying to get information on a material called Kyanite. It was
> recommended that I add this to my clay body (04 terracotta) to help
> prevent cracking. Is this true and what percentage should I use.
> The technique I use on my 22 inch platters is to reheat them gently after
> the initial base coat firing and then use slip trailers to add more
> glaze in a controled pattern, the heat of the platter sets the glaze
> where I lay it while I'm working on it at the wheel. My grog percentage
> is five pounds fine and five medium. I also add nylon fibers to help with
> the extrusions of the foot and rim which I then add to hump molded clay.
> Any thoughts on this would be helpful.
> Frank, in sunny and warm (80) Philadelphia.
>
Sarah Barnes on wed 15 oct 97
HI. If you need Kyanite and leave on the East coast you can order
directly from the Kyanite Mining Company, Dillwyn Virginia, 804-983-2043.
Standard Ceramics charges areound .60 cents a pound, the company is much
cheaper although they just raised their prices, i don't think its above
20 cents per pound.
Hope this information helps
Sarah
Baltimore, md
Marvin Goff on sun 25 feb 01
Does anyone know if kyanite enters into the melt of a clay body or does =
it act only as a grog with desirable expansion properties??
Marvin Goff
Louis Hill on tue 17 dec 02
John, One catalog I have says "Kyanite is a member of
the sillimanite group of minerals. They are super-duty
refractories and can aid in manufacturing a
mechanically strong clay body,which will also have
tremendous resistance to thermal shock." Calcined
kyanite may also be called mullite I believe.
SiO2 38.65%
Al2O3 61.80%
Fe2O3 0.94%
TiO2 0.95%
CaO 0.05%
MgO 0.06%
Alkalies .42%
LOI 9.21%
I hope this helpful.
Louis Hill in Birmingham where the sun has
finally broken through for two days in a row.
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Nils Lou on sat 12 jun 10
I have used kyanite in raku bodies for larger
pieces to prevent cracking. as much as 50%!
large slabs that cracked in drying or in bisque
were beneficiated with addition of kyanite.
note: floured zirconia and colloidal silica is
not ITC. It may be an effective coating, but it
should not be referred to as ITC which is quite a different animal.
milk of magnesia is an effective coating, but is
not ITC.=3D20
nils lou, professor of art
http://nilslou.blogspot.com
www.tinyurl.com/bpc5nm
503.883.2274
"Play is the essence of creativity", and
"What is not brought forward into consciousness....
we later call Fate", Carl Jung
tony clennell on sat 12 jun 10
Nils: I agree the formula I provided is not ITC. If a company provides
you with a product to endorse then of course it is the brass ring.
For most potters a couple of hundred bucks a gallon for a ceramic
coating is a lot of money. I provide a formula for a product that is
a damn fine coating that comes in at a fraction of the price and I get
nothing for it other than the satisfaction of helping potters survive.
Endorsements always come at a cost.
All the best,
Tony
On Sat, Jun 12, 2010 at 12:13 PM, Nils Lou wrote:
> I have used kyanite in raku bodies for larger
> pieces to prevent cracking. as much as 50%!
> large slabs that cracked in drying or in bisque
> were beneficiated with addition of kyanite.
>
> note: floured zirconia and colloidal silica is
> not ITC. It may be an effective coating, but it
> should not be referred to as ITC which is quite a different animal.
> milk of magnesia is an effective coating, but is
> not ITC.
>
> nils lou, professor of art
> http://nilslou.blogspot.com
> www.tinyurl.com/bpc5nm
> 503.883.2274
> "Play is the essence of creativity", and
> "What is not brought forward into consciousness....
> we later call Fate", Carl Jung
>
--
http://sourcherrypottery.com
http://smokieclennell.blogspot.com
John Britt on sun 13 jun 10
Tony,
Thanks for taking the time to post this coating recipe. There are many
coatings and ITC is not the only one that is effective. There are not ma=
=3D
ny
potters who can afford $140 or whatever it is a gallon/bucket.
We have used Zircon 50% /EPK 50%, Seraset (high temperature mortar) thinn=
=3D
ed
with water and added 25 - 50% alumina hydrate, etc.=3D20
Let's hear it for the working potter!
John Britt
www.johnbrittpottery.com
mel jacobson on mon 20 aug 12
kerry brooks uses 30-40 mesh kyanite in her
tile production business. it works well with the
expansion trouble with the glass/clay problem.
she has found that the 100 mesh is not
good for her materials..it is too fine and
does not work at all.
me
http://www.visi.com/~melpots/
clayart page below:
http://www.visi.com/~melpots/clayart.html
http://www.21stcenturykilns.com/
ronroy@CA.INTER.NET on mon 20 aug 12
Just to make sure everyone understands - what my experience is.
Heavier mesh sizes of Kyanite can cut - it's a needle shape crystal -
not a problem for hand building but hard on the hands when throwing.
I have designed many bodies with 100 mesh kyanite - up to 20% - and
there have been no problems reported. It does not turn into
cristobalite in high fire stonewares like fine silica does - a good
solution to what can be a serious problem.
RR
Quoting mel jacobson :
> kerry brooks uses 30-40 mesh kyanite in her
> tile production business. it works well with the
> expansion trouble with the glass/clay problem.
>
> she has found that the 100 mesh is not
> good for her materials..it is too fine and
> does not work at all.
> me
> http://www.visi.com/~melpots/
> clayart page below:
> http://www.visi.com/~melpots/clayart.html
> http://www.21stcenturykilns.com/
>
John Post on mon 20 aug 12
My experiences with kyanite are different than RR's. I've used bodies
with 19% kyanite (48 mesh) in them and thrown on the wheel with them
and never had a cut, ever. I prefer the feel of kyanite and mullite
over grog any day.
John Post
Sterling Heights, Michigan
http://www.johnpost.us
Follow me on Twitter
https://twitter.com/UCSArtTeacher
On Aug 20, 2012, at 4:52 PM, ronroy@CA.INTER.NET wrote:
> Just to make sure everyone understands - what my experience is.
>
> Heavier mesh sizes of Kyanite can cut - it's a needle shape crystal -
> not a problem for hand building but hard on the hands when throwing.
>
> RR
>
>
> Quoting mel jacobson :
>
>> kerry brooks uses 30-40 mesh kyanite in her
>> tile production business. it works well with the
>> expansion trouble with the glass/clay problem.
>>
>> she has found that the 100 mesh is not
>> good for her materials
Hank Murrow on mon 20 aug 12
On Aug 20, 2012, at 1:52 PM, ronroy@CA.INTER.NET wrote:
> Just to make sure everyone understands - what my experience is.
>=3D20
> Heavier mesh sizes of Kyanite can cut - it's a needle shape crystal -
> not a problem for hand building but hard on the hands when throwing.
>=3D20
> I have designed many bodies with 100 mesh kyanite - up to 20% - and
> there have been no problems reported. It does not turn into
> cristobalite in high fire stonewares like fine silica does - a good
> solution to what can be a serious problem.
Dear Ron;=3D20
I have been using up to 33% Kyanite 35 mesh in my Tea body with good =3D
results. I don't experience much abrasion when throwing, but I do =3D
stretch and carve the pots to thin them down when they are still soft. =3D
If I were throwing thinner to start with, perhaps I would experience =3D
some abrasion?
Cheers, Hank
The body in question: 33% Kyanite 35 mesh, 33% ball, 33% kaolin, 1% Vee =3D
Gum T. Anagama fired.
Same body, also fired in anagama to C13+.=3D
ronroy@CA.INTER.NET on tue 21 aug 12
Thanks for this John - I can remember trying to throw with 35 mesh in
some clay and found it unpleasant.
There is a good argument for using the lower mesh sizes - the needle
like particles provide mechanical strength during drying - very good
for bigger jobs.
RR
Quoting John Post :
> My experiences with kyanite are different than RR's. I've used bodies
> with 19% kyanite (48 mesh) in them and thrown on the wheel with them
> and never had a cut, ever. I prefer the feel of kyanite and mullite
> over grog any day.
>
> John Post
> Sterling Heights, Michigan
>
> http://www.johnpost.us
>
> Follow me on Twitter
> https://twitter.com/UCSArtTeacher
>
>
>
>
>
>
> On Aug 20, 2012, at 4:52 PM, ronroy@CA.INTER.NET wrote:
>
>> Just to make sure everyone understands - what my experience is.
>>
>> Heavier mesh sizes of Kyanite can cut - it's a needle shape crystal -
>> not a problem for hand building but hard on the hands when throwing.
>>
>> RR
>>
>>
>> Quoting mel jacobson :
>>
>>> kerry brooks uses 30-40 mesh kyanite in her
>>> tile production business. it works well with the
>>> expansion trouble with the glass/clay problem.
>>>
>>> she has found that the 100 mesh is not
>>> good for her materials
>
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