Quinn Bougher on fri 2 mar 12
This is my first time posting. I've been a longtime user of the listserv=
=3D
though.
My question is regarding my clear glaze. Here's the issue- for the first
couple of days after mixing the batch (about 4-7) the glaze is very thin,=
=3D
and hard pans something terrible. despite this , the application process=
=3D
goes incredibly smoothly. The glaze sheets nicely, drips off the rim, and=
=3D
any remaining drips are smooth enough that they don't show up in the firi=
=3D
ng.=3D20
After one week, everything changes. The glaze becomes thick, gelatinous, =
=3D
and
puffy. Glazing becomes a chore at this point. The glaze wont drip (even =
=3D
off
a finger), it leaves HUGE drip marks where it should sheet, and dries ove=
=3D
r
the course of 10 minutes. At least it is no longer hardpanning...
I know that I need to overcome the surface tension of the slurry to solve=
=3D
my
problems. But nothing seems to thin it out. Adding H2O just makes the gla=
=3D
ze
layer thinner, but doesn't help application. Darvan 7, Darvan 811 and sod=
=3D
ium
silicate are all useless and have no effect. Epsom salts (and other
flocculants) make the problems worse.
Can EPK be the problem? or could the amount of frit in this glaze be
deflocculating the glaze slurry? (after the first week, the glaze falls o=
=3D
ut
like a flocculated slurry though- not hardpanning, but forming flocs and
falling out in 5 minutes)
One other thing before the recipe- the water on top of the glaze is a dir=
=3D
ty
golden brown. If I sub ball clay for the EPK the color goes away, but mo=
=3D
st
of the application issues remain.
here's the recipe-
cone 6 clear
FELDSPAR CUSTER 13
Whiting=3D09 16
FRIT CC 250=3D09 12
Frit 3249=3D09 6
Frit 3124=3D09 6
Frit 3195=3D09 4
SILICA 400 MESH=3D09 29
KAOLIN EPK=3D09 12
bentonite HPM-20=3D09 2
I thank you for your response! I've been beating my head against the wal=
=3D
l
for months, and there seems to be very little in the archives on this sub=
=3D
ject...
Paul Lewing on sat 3 mar 12
On Mar 2, 2012, at 3:37 PM, Quinn Bougher wrote:
the glaze is very thin,
and hard pans something terrible.
I'd say that was because there's so much frit in there. Although it
does have quite a lot of clay as well to help it stay in suspension.
I'd have to run this thing through glaze calculation software, but I
think any glaze with four different frits is ridiculous. I'm not
familiar with all of them, but the ones in here I know are not that
different from each other. I'd bet you could reformulate that to use
only one, possibly two, frits.
Paul Lewing
www.paullewingtile.com
www.paullewingart.com
ronroy@CA.INTER.NET on sat 3 mar 12
Hi Quinn,
It may be the water - get some demineralized or distilled water and
mix up a new batch.
I think I can simplify that recipe - there might be some flocculator
coming in with one of those frits.
Try the purified water first - it has worked with many before.
RR
Quoting Quinn Bougher :
> This is my first time posting. I've been a longtime user of the listserv
> though.
>
> My question is regarding my clear glaze. Here's the issue- for the first
> couple of days after mixing the batch (about 4-7) the glaze is very thin,
> and hard pans something terrible. despite this , the application process
> goes incredibly smoothly. The glaze sheets nicely, drips off the rim, and
> any remaining drips are smooth enough that they don't show up in the firi=
ng.
>
> After one week, everything changes. The glaze becomes thick, gelatinous, =
and
> puffy. Glazing becomes a chore at this point. The glaze wont drip (even =
off
> a finger), it leaves HUGE drip marks where it should sheet, and dries ove=
r
> the course of 10 minutes. At least it is no longer hardpanning...
>
> I know that I need to overcome the surface tension of the slurry to solve=
my
> problems. But nothing seems to thin it out. Adding H2O just makes the gla=
ze
> layer thinner, but doesn't help application. Darvan 7, Darvan 811 and sod=
ium
> silicate are all useless and have no effect. Epsom salts (and other
> flocculants) make the problems worse.
>
> Can EPK be the problem? or could the amount of frit in this glaze be
> deflocculating the glaze slurry? (after the first week, the glaze falls o=
ut
> like a flocculated slurry though- not hardpanning, but forming flocs and
> falling out in 5 minutes)
>
> One other thing before the recipe- the water on top of the glaze is a dir=
ty
> golden brown. If I sub ball clay for the EPK the color goes away, but mo=
st
> of the application issues remain.
>
> here's the recipe-
> cone 6 clear
>
> FELDSPAR CUSTER 13
> Whiting 16
> FRIT CC 250 12
> Frit 3249 6
> Frit 3124 6
> Frit 3195 4
> SILICA 400 MESH 29
> KAOLIN EPK 12
> bentonite HPM-20 2
>
> I thank you for your response! I've been beating my head against the wal=
l
> for months, and there seems to be very little in the archives on
> this subject...
>
Quinn Bougher on sat 3 mar 12
Thanks to all who have responded so far! I now am testing a batch with a =
=3D
larger mesh=3D20
silica.
To Ron Roy, thank you for taking a look. I have tried distiller water. I =
=3D
will be trying it again=3D20
when I get into the studio next week. My experience in the past has been =
=3D
that this does not=3D20
solve the issues though.
This recipe can be simplified by just using cc250 and 3249. 3124 and 3195=
=3D
are the=3D20
components of cc250, and I've been splitting the difference because of a =
=3D
bad experience=3D20
with frit that was ground too coarse.
The 3249 is a magnesium frit, in the mix to lower the expansion and help =
=3D
with crazing.=3D20
Could the magnesium be leaching out of that?
Ben Morrison on sat 3 mar 12
There are many clear cone 6 glaze recipes out there to choose f=3D
Quinn,=3D0A=3D0AThere are many clear cone 6 glaze recipes out there to choo=
se f=3D
rom. This isn't one I'd choose personally for several reasons, but primaril=
=3D
y because frit is expensive by comparison to many feldspars that could be u=
=3D
sed in place of the majority of that glaze recipe. If it was me I'd find a =
=3D
better recipe to start with that isn't so problematic or so expensive.=3D0A=
=3D
=3D0ABest of luck,=3D0A=3D0ABen=3D0A=3D0A=3D0A_____________________________=
___=3D0A From:=3D
Quinn Bougher =3D0ATo: Clayart@LSV.CERAMICS.ORG =3D0AS=
ent:=3D
Friday, March 2, 2012 3:37 PM=3D0ASubject: Question for the glaze guys- gl=
az=3D
e poise revisited=3D0A =3D0AThis is my first time posting.=3DA0 I've been a=
longt=3D
ime user of the listserv=3D0Athough.=3D0A=3D0AMy question is regarding my c=
lear g=3D
laze. Here's the issue- for the first=3D0Acouple of days after mixing the b=
at=3D
ch (about 4-7) the glaze is very thin,=3D0Aand hard pans something terrible=
.=3D
=3DA0 despite this , the application process=3D0Agoes incredibly smoothly. =
The =3D
glaze sheets nicely, drips off the rim, and=3D0Aany remaining drips are smo=
ot=3D
h enough that they don't show up in the firing. =3D0A=3D0AAfter one week, e=
very=3D
thing changes. The glaze becomes thick, gelatinous, and=3D0Apuffy. Glazing =
be=3D
comes a chore at this point.=3DA0 The glaze wont drip (even off=3D0Aa finge=
r), =3D
it leaves HUGE drip marks where it should sheet, and dries over=3D0Athe cou=
rs=3D
e of 10 minutes. At least it is no longer hardpanning...=3D0A=3D0AI know th=
at I=3D
need to overcome the surface tension of the slurry to solve my=3D0Aproblem=
s.=3D
But nothing seems to thin it out. Adding H2O just makes the glaze=3D0Alaye=
r =3D
thinner, but doesn't help application. Darvan 7, Darvan 811 and sodium=3D0A=
si=3D
licate are all useless and have no effect. Epsom salts (and other=3D0Aflocc=
ul=3D
ants) make the problems worse.=3D0A=3D0ACan EPK be the problem?=3DA0 or cou=
ld the=3D
amount of frit in this glaze be=3D0Adeflocculating the glaze slurry? (afte=
r =3D
the first week, the glaze falls out=3D0Alike a flocculated slurry though- n=
ot=3D
hardpanning, but forming flocs and=3D0Afalling out in 5 minutes)=3D0A=3D0A=
One ot=3D
her thing before the recipe- the water on top of the glaze is a dirty=3D0Ag=
ol=3D
den brown.=3DA0 If I sub ball clay for the EPK the color goes away, but mos=
t=3D
=3D0Aof the application issues remain.=3D0A=3D0Ahere's the recipe-=3D0Acone=
6 clear=3D
=3D0A=3D0AFELDSPAR CUSTER=3DA0 13=3D0AWhiting=3DA0=3DA0=3DA0 =3DA0 =3DA0 =
=3DA0 =3DA0 =3DA0 =3DA0 16=3D
=3D0AFRIT CC 250=3DA0=3DA0=3DA0 =3DA0 =3DA0 12=3D0AFrit 3249=3DA0=3DA0=3DA0=
=3DA0 =3DA0 =3DA0 =3DA0 =3DA0=3D
=3DA0 6=3D0AFrit 3124=3DA0=3DA0=3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =
6=3D0AFrit 3195=3DA0=3DA0=3D
=3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 4=3D0ASILICA 400 MESH=3DA0=3DA0=
=3DA0 =3DA0 =3DA0 29=3D0AKAOL=3D
IN EPK=3DA0=3DA0=3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 =3DA0 12=3D0Abentonite =
HPM-20=3DA0=3DA0=3DA0 =3DA0 =3D
=3DA0 =3DA0 2=3D0A=3D0AI thank you for your response!=3DA0 I've been beatin=
g my head =3D
against the wall=3D0Afor months, and there seems to be very little in the a=
rc=3D
hives on this subject...
Autumn Downey on sun 4 mar 12
If you were looking for another Cone 6 clear, this one seems to work
quite well.
(an offshoot of a Ron Roy glaze)
Autumn Downey
Hybrid clear
Code Number:
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
SILICA...................... 900.00
EPK KAOLIN.................. 1100.00
WOLLASTONITE................ 1000.00
FRIT 3134................... 900.00
F-4 FELDSPAR................ 1000.00
TALC........................ 100.00
=3D=3D=3D=3D=3D=3D=3D=3D=3D
5000.00
CaO 0.74* 13.92 15.73
MgO 0.06* 0.79 1.24
K2O 0.03* 1.07 0.72
Na2O 0.16* 3.35 3.43
TiO2 0.00 0.10 0.08
Al2O3 0.38 12.83 7.98
B2O3 0.18 4.29 3.91
P2O5 0.00 0.06 0.03
SiO2 3.16 63.27 66.75
Fe2O3 0.01 0.29 0.12
MnO 0.00* 0.02 0.02
Cost: 1.81
Calculated LOI: 3.10
Imposed LOI:
Si:Al: 8.37
SiB:Al: 8.86
Thermal Expansion: 6.94
Formula Weight: 299.96
Quinn Bougher wrote:
> This is my first time posting. I've been a longtime user of the listserv
> though.
>
> My question is regarding my clear glaze. Here's the issue- for the first
> couple of days after mixing the batch (about 4-7) the glaze is very thin,
> and hard pans something terrible. despite this , the application process
> goes incredibly smoothly. The glaze sheets nicely, drips off the rim, and
> any remaining drips are smooth enough that they don't show up in the firi=
ng.
>
> After one week, everything changes. The glaze becomes thick, gelatinous, =
and
> puffy. Glazing becomes a chore at this point. The glaze wont drip (even =
off
> a finger), it leaves HUGE drip marks where it should sheet, and dries ove=
r
> the course of 10 minutes. At least it is no longer hardpanning...
>
> I know that I need to overcome the surface tension of the slurry to solve=
my
> problems. But nothing seems to thin it out. Adding H2O just makes the gla=
ze
> layer thinner, but doesn't help application. Darvan 7, Darvan 811 and sod=
ium
> silicate are all useless and have no effect. Epsom salts (and other
> flocculants) make the problems worse.
>
> Can EPK be the problem? or could the amount of frit in this glaze be
> deflocculating the glaze slurry? (after the first week, the glaze falls o=
ut
> like a flocculated slurry though- not hardpanning, but forming flocs and
> falling out in 5 minutes)
>
> One other thing before the recipe- the water on top of the glaze is a dir=
ty
> golden brown. If I sub ball clay for the EPK the color goes away, but mo=
st
> of the application issues remain.
>
> here's the recipe-
> cone 6 clear
>
> FELDSPAR CUSTER 13
> Whiting 16
> FRIT CC 250 12
> Frit 3249 6
> Frit 3124 6
> Frit 3195 4
> SILICA 400 MESH 29
> KAOLIN EPK 12
> bentonite HPM-20 2
>
> I thank you for your response! I've been beating my head against the wal=
l
> for months, and there seems to be very little in the archives on this sub=
ject...
>
>
>
>
Quinn Bougher on mon 5 mar 12
Ron-
The analysis for CC250 (from digitalfire) is:
CaO 13.51
K2O 5.1
Na20 6.22
Al2O3 10.5
B2O3 15.95
SiO2 53.3
Thank you!
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