Barney Adams on tue 5 sep 00
Hi,
I want to develop a stone matt and was wondering if there are guidelines
to achiving this.
One recipe I have from clayart maybe a starting point, but it is very
low on silica. Is this
required for this stoney look? The recipe is as follows:
Stony Matt ^6
Bone Ash 6.0
Neph Syen 26.1
Magnesium Carb 2.4
Wollastonite 13.2
strontium carb 31.6
EPK 15.1
Tin Oxide 5.6
Copper Oxide 3.0
I imagine the strontium helps the matt dryness and the bone ash for
texture.
Should that be my starting point? High strontium, high alumina and a
generous
amount of bone ash and some melting fluxes.
Maybe along the below lines. I'm still low on silica but moving in the
right direction.
Is the tin in the above recipe important for this effect?
NEPH SYEN........ 33.00 33.00%
STRONTIUM CARBONATE. 22.00 22.00%
BONE ASH............ 8.00 8.00%
EPK KAOLIN.......... 22.00 22.00%
TALC................ 3.00 3.00%
SILICA.............. 10.00 10.00%
ZINC OXIDE.......... 2.00 2.00%
========
100.00
CaO 0.24* 5.37%
MnO2 0.00 0.01%
MgO 0.07* 1.17%
K2O 0.05* 1.82%
Na2O 0.15* 3.66%
ZnO 0.07* 2.24%
Fe2O3 0.00 0.21%
TIO2 0.00 0.07%
AL2O3 0.44 17.82%
SiO2 1.96 46.61%
P2O5 0.07 3.82%
SrO 0.42* 17.21%
COST/KG 3.97
Si:Al 4.45
SiB:Al 4.60
EXPAN643.40
I know just try it. I will but like my first attempt at a shino I may be
out of the ballpark.
Thanks
Barney
Sharon31 on wed 6 sep 00
Hello Barney!
Let us start with the credit to BEHRENS which in his book appears this
recipe.
----- Original Message -----
From: Barney Adams
To:
Sent: Tuesday, September 05, 2000 05:29
Subject: Stone matt glaze question
> Hi,
> I want to develop a stone matt and was wondering if there are guidelines
> to achiving this.
> One recipe I have from clayart maybe a starting point, but it is very
> low on silica. Is this
> required for this stoney look? The recipe is as follows:
>
> Stony Matt ^6
> Bone Ash 6.0
> Neph Syen 26.1
> Magnesium Carb 2.4
> Wollastonite 13.2
> strontium carb 31.6
> EPK 15.1
> Tin Oxide 5.6
> Copper Oxide 3.0
This is a great glaze, I payed a lot, to buy strontium carb (especialy to
U.S. post office).Working with strontium carb makes you feel better than
doing the same glaze with Barium caebonate that is 'famous' as a
stony-maker.
> I imagine the strontium helps the matt dryness and the bone ash for...
I can tell you this: The copper oxide 3.0, is my
adding because I am copper oxide addicted!
The tin oxide, helps to matte it.
I send you here to a link, there is a great article+recipes of Val Cushing
http://www.studiopotter.org/articles/index.htm
Firing in Oxidation to C/4.5.6
by Val Cushing
http://www.studiopotter.org/articles/art0009.htm
Among the recipes you will find three recpes that might help you.
A few weeks ago I posted some matte glazes, including the one you sent here.
Go to the archivs you will find them .I don`t think you have to deal with
every material separately, but in the whole.I would not serve food in a
glaze like this, you have said already that it was low in silica , stony,
and therefor not smooth.
The advantage of stony, glazes is that -as they are, not foodsafe, you can
try widely and wildly!
A good site, to learn through testing is the ceramic web, You ask , let us
say, glaze with strontium carb. ^6 and you get a list. You don't have to
test all of them, but you can see how they are built :
http://art.sdsu.edu/ceramicsweb/ GlazeBase Glaze Database Search Form.
@
@
@
And remember us when you will have a great glaze!
Ababi Sharon
sharon@shoval.org.il
http://www.milkywayceramics.com/cgallery/asharon.htm
Ron Roy on thu 7 sep 00
Hi Barney,
I think the tin is there to warm it up a bit - you can use some rutile - 1
or 2 % to warm it - also helps to give the crystals (true clay matts
recrystallize on cooling) a place to start. Matte glaze usually wind up
out of the limits because they are short of silica - the clay mattes
anyway. This one has a low enough silica to alumina ratio to be a matte and
enough strontium (oversupplied) to be a matte even if you raise the ratio.
I think your version will not melt at cone 6 - you might try putting in
enough f3134 to make it melt - don't forget to cut back the CaO and Na2O if
you do that. It will bring the expansion down - maybe even enough to stop
the crazing.
Let me know what happens - RR
>I want to develop a stone matt and was wondering if there are guidelines
>to achiving this.
>One recipe I have from clayart maybe a starting point, but it is very
>low on silica. Is this
>required for this stoney look? The recipe is as follows:
>
>Stony Matt ^6
>Bone Ash 6.0
>Neph Syen 26.1
>Magnesium Carb 2.4
>Wollastonite 13.2
>strontium carb 31.6
>EPK 15.1
>Tin Oxide 5.6
>Copper Oxide 3.0
>
>I imagine the strontium helps the matt dryness and the bone ash for
>texture.
>Should that be my starting point? High strontium, high alumina and a
>generous
>amount of bone ash and some melting fluxes.
>Maybe along the below lines. I'm still low on silica but moving in the
>right direction.
>Is the tin in the above recipe important for this effect?
> NEPH SYEN........ 33.00 33.00%
> STRONTIUM CARBONATE. 22.00 22.00%
> BONE ASH............ 8.00 8.00%
> EPK KAOLIN.......... 22.00 22.00%
> TALC................ 3.00 3.00%
> SILICA.............. 10.00 10.00%
> ZINC OXIDE.......... 2.00 2.00%
> ========
> 100.00
>
> CaO 0.24* 5.37%
> MnO2 0.00 0.01%
> MgO 0.07* 1.17%
> K2O 0.05* 1.82%
> Na2O 0.15* 3.66%
> ZnO 0.07* 2.24%
> Fe2O3 0.00 0.21%
> TIO2 0.00 0.07%
> AL2O3 0.44 17.82%
> SiO2 1.96 46.61%
> P2O5 0.07 3.82%
> SrO 0.42* 17.21%
>
> COST/KG 3.97
> Si:Al 4.45
> SiB:Al 4.60
> EXPAN643.40
>I know just try it. I will but like my first attempt at a shino I may be
>out of the ballpark.
>Thanks
>Barney
Ron Roy
93 Pegasus Trail
Scarborough
Ontario, Canada
M1G 3N8
Evenings 416-439-2621
Fax 416-438-7849
Barney Adams on thu 7 sep 00
Thanks Ron,
Would spodumene be ok to add? It adds Al2O3,can lower the expansion while adding
to melt. I'm thinking of removing the Neph completely and supply MgO, CaO,
strontium. and zinc.
I thought I'd go for all the matt fluxes with a vengeance. The spodumene would
kinda fill in for
the neph.
Is there a limit to the % of EPK I want in the glaze?
I'm trying to use what I have on hand. I could use F3124 instead of the F3134,
but how about F3269? It tends to bump up the expansion, but I have some I don't
ever use.. I'll play with it and see what I can come up with. I also have some
F5301.
I'll try a version with all 3 just to see what effect the 3 have.
Barney
Ron Roy wrote:
> Hi Barney,
>
> I think the tin is there to warm it up a bit - you can use some rutile - 1
> or 2 % to warm it - also helps to give the crystals (true clay matts
> recrystallize on cooling) a place to start. Matte glaze usually wind up
> out of the limits because they are short of silica - the clay mattes
> anyway. This one has a low enough silica to alumina ratio to be a matte and
> enough strontium (oversupplied) to be a matte even if you raise the ratio.
> I think your version will not melt at cone 6 - you might try putting in
> enough f3134 to make it melt - don't forget to cut back the CaO and Na2O if
> you do that. It will bring the expansion down - maybe even enough to stop
> the crazing.
>
> Let me know what happens - RR
>
| |
|
