Alyssa Ettinger on fri 22 dec 06
the most basic of cone ^6 clear transparent glaze
i need a foolproof cone ^6 transparent glaze, for oxidation, for porcelain,
food safe, with as few ingredients as possible. to compare, i'm taking about
something as easy and low maintenance as a popover recipe: (1 cup milk, one
cup flour, 1 egg, 1 tsp salt.)
anyone? ron?
Nancy on fri 22 dec 06
Alyssa
I tried the G1214 5/20 recipe which IS simple BUT does not do well on my
Laguna clay bodies....it crazes horribly and the pieces are not good
even for my use. I hope someone can provide a good stable recipe, then
I could use it too :D
Nancy
www.hilltoppottery.com
NancAlyssa Ettinger wrote:
> the most basic of cone ^6 clear transparent glaze
>
> i need a foolproof cone ^6 transparent glaze, for oxidation, for porcelain,
> food safe, with as few ingredients as possible. to compare, i'm taking about
> something as easy and low maintenance as a popover recipe: (1 cup milk, one
> cup flour, 1 egg, 1 tsp salt.)
>
> anyone? ron?
>
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claystevslat on fri 22 dec 06
Alyssa -- Depending on your clay, Ian Begg's Clear comes to
Mind -- 50% frit 3134, 30% EPK, 20% Silica. No bentonite
required, doesn't run readily but will get cloudy where too
thick. Down side -- you may have crazing issues.
If you're willing to get into GB in spite of the various
issues, using GB in lieu of 3134 makes it another fameous
^6 glaze, though I can't remember who devised it. With GB
you might not have crazing (there's lots less Na in 3134
than in GB).
-- Steve Slatin
--- In clayart@yahoogroups.com, Alyssa Ettinger wrote:
>
> the most basic of cone ^6 clear transparent glaze
>
> i need a foolproof cone ^6 transparent glaze, for oxidation, for
porcelain,
> food safe, with as few ingredients as possible.
Alyssa Ettinger on fri 22 dec 06
crazing is actually the biggest issue here, because i need the glaze for the
*inside* of cups.
because i've yet to find a stable one that works with all of my clay bodies
(standard's portland and grolleg porcelains, and seeley's porcelain slips)
i've been using extremely thin coats of commercial glaze. certainly easy
application and foolproof... and, as you know, wickedly expensive.
Alisa Liskin Clausen on sat 23 dec 06
On Fri, 22 Dec 2006 00:23:55 -0500, Alyssa Ettinger wrote:
>the most basic of cone ^6 clear transparent glaze
>
>i need a foolproof cone ^6 transparent glaze, for oxidation, for
porcelain,
>food safe, with as few ingredients as possible. to compare, i'm taking
about
>something as easy and low maintenance as a popover recipe: (1 cup milk,
one
>cup flour, 1 egg, 1 tsp salt.)
>
>anyone? ron?
>
Dear Alyssa
I do not know what type of clay you use, but you say porcelain.
Porcelains by most standards need to be fired much higher than cone 6.
For example, the Limoges or and English porcelain body I use periodically
must be fired to miniumum 1260c. Your crazing issues may be due to your
clay is not vitrified at cone 6. You could be lucky and find a cone 6
glaze that will fit, but that will of couse be a matter of testing. I
would be surprised if you get a recipe that will work from the get go.
Asking for a fool proof recipe is not realistic because no one except you
is firing your clay and kiln. In all cases, you must test and perhaps
adjust.
The idea of a glaze with few ingredients is often not a good idea. If you
get dependent on such a glaze and one day come in a situation where you
need to substitute one of the materials, you will have a hard time because
such a large percent of the glaze must be subbed.
Again, it could be your porcelain is vitrified at cone 6. I think in the
states there are some lower fired porcelains. However, if crazing is an
issue with many cone 6 glazes you have tried, I would question your firing
temp. for the clay you are using. You know that crazing is bad fit
between your clay and glaze.
Best regards,
Alisa in Denmark
It is Christmas in Denmark. Little Christmas Evening as it called.
A time to go home and be with family and friends.
I am happy to close this year with figures from sales that show this year
my studio has officially become my job. Earnings from my sales will not
stuff my mattress too high, but I am really satisfied. After 5 years of
hard work, this year is the first yearI can say I have made a business out
of my studio work.
Alyssa Ettinger on sun 24 dec 06
alisa,
i'm using cone 6 porcelain, so the issues you're describing shouldn't apply.
plus, if there's a cone 6 commercial glaze for it, there has to be a recipe
(and use the commercial as back-up as needed because, sadly, because both
the amaco and duncan i use never fail and are always spot-on perfect--and i
am not kind to them... i mix them with other brands, thin them with tons of
water, use them lumpy because i don't mix them well... foolproof.)
alyssa
www.alyssaettinger.com
Kathy Greaves on fri 29 dec 06
Alyssa,
Here are a couple of recipes for a clear c/6 glaze. KG1 works well for =
me
on most c/6 porcelains, but has crazed a couple of times. In my =
comments
you'll see HCSB and GBG1. HCSB and GBG1 are from MC6G, and neither =
worked
well enough as a clear glaze for me, but the combination of the two does
well. It has 5 ingredients, though, so it's not the simplest recipe I =
have.
The simplest, Ravenscrag Recipe A, I haven't tried yet, but the low
expansion coefficient tells me it might work for you. Has anyone else =
tried
the Ravenscrag recipe on c/6 porcelain? If so, what do you think?
Recipe Name: KG1
Cone: 6 Color: clear
Firing: Oxidation Surface: Glossy
Amount Ingredient
28.2 Frit--Ferro 3134
19.3 Silica
33.3 Kaolin--EPK
13.3 Wollastonite
5.9 Talc
100 Total
Unity Oxide
.155 Na2O
.005 K2O
.161 MgO
.68 CaO
1.000 Total
.404 Al2O3
.302 B2O3
.006 Fe2O3
3.111 SiO2
.004 TiO2
.001 P2O5
7.7 Ratio
64.3 Exp
Comments: Playing with line blend - still no automatic recipe =
conversion.
Came up with this as midpoint molar equiv. of HCSB & GBG1. So far, it =
works
well. Tentative new name KG1
-----------------------------------
Calculations by GlazeMasterT
www.masteringglazes.com
------------------------------------
Recipe Name: Ravenscrag Recipe A - Clear Glossy
Cone: 6 Color: clear
Firing: Oxidation Surface: Glossy
Amount Ingredient
80 Ravenscrag slip
20 Frit--Ferro 3134
100 Total
Unity Oxide
.16 Na2O
.115 K2O
.151 MgO
.574 CaO
1.000 Total
.447 Al2O3
.267 B2O3
.017 Fe2O3
4.324 SiO2
.017 TiO2
9.7 Ratio
65.7 Exp
Comments:
-----------------------------------
Calculations by GlazeMasterT
www.masteringglazes.com
------------------------------------
I hope this helps!
Kathy
Alyssa Ettinger on sun 31 dec 06
it seems i'll be doing a giant amount of glaze testing! thanks everyone.
so here's a question: is there any way to get any of these "home-made"
glazes (and i hate that word, i just couldn't think of another...) to be as
thick and non-settling as a commercial glaze? (again, not using the right
words)...
let me explain: i use a decent amount of clear glaze on the inside of
once-fire cone 6 porcelain cups. (i once-fire because the pieces withstand
it, and it saves me a lot of $$ on firing.)
so, i'm pouring the glaze into a thin piece of greenware, swirling it around
and pouring it out. i do this pretty quickly because i don't want the piece
to crumble. this is one of the reasons why commercial glaze has been so
successful for me, because it's so suspended and so sticky, for lack of a
better word, that i have a very low rate of crumbling cups.
how can i make a home-made glaze act this way?
Ron Roy on sun 31 dec 06
Hi everyone!
The first glaze looks like a stable glaze - the calculated expansion is on
the low side so I am surprised to hear there is some crazing - could it be
due to opening a kiln too soon? I would have said I would be more
comfortable with the expansion raised a bit.
The second glaze also looks like it may be stable - it's expansion is a
little higher than the first ones but still a bit on the low side. I would
not expect either to craze on most cone 6 bodies.
I would also recommend trying 25 Frit 3134 and 75 Ravenscrag slip - still a
stable glaze but with more melt.
RR
>Here are a couple of recipes for a clear c/6 glaze. KG1 works well for me
>on most c/6 porcelains, but has crazed a couple of times. In my comments
>you'll see HCSB and GBG1. HCSB and GBG1 are from MC6G, and neither worked
>well enough as a clear glaze for me, but the combination of the two does
>well. It has 5 ingredients, though, so it's not the simplest recipe I have.
>The simplest, Ravenscrag Recipe A, I haven't tried yet, but the low
>expansion coefficient tells me it might work for you. Has anyone else tried
>the Ravenscrag recipe on c/6 porcelain? If so, what do you think?
>
>Recipe Name: KG1
>
>Cone: 6 Color: clear
>Firing: Oxidation Surface: Glossy
>
>Amount Ingredient
>28.2 Frit--Ferro 3134
>19.3 Silica
>33.3 Kaolin--EPK
>13.3 Wollastonite
>5.9 Talc
>
>100 Total
>
>
>Unity Oxide
>.155 Na2O
>.005 K2O
>.161 MgO
>.68 CaO
>1.000 Total
>
>.404 Al2O3
>.302 B2O3
>.006 Fe2O3
>
>3.111 SiO2
>.004 TiO2
>.001 P2O5
>
>7.7 Ratio
>64.3 Exp
>
>Comments: Playing with line blend - still no automatic recipe conversion.
>Came up with this as midpoint molar equiv. of HCSB & GBG1. So far, it works
>well. Tentative new name KG1
>-----------------------------------
>Calculations by GlazeMasterT
>www.masteringglazes.com
>------------------------------------
>Recipe Name: Ravenscrag Recipe A - Clear Glossy
>
>Cone: 6 Color: clear
>Firing: Oxidation Surface: Glossy
>
>Amount Ingredient
>80 Ravenscrag slip
>20 Frit--Ferro 3134
>
>100 Total
>
>
>Unity Oxide
>.16 Na2O
>.115 K2O
>.151 MgO
>.574 CaO
>1.000 Total
>
>.447 Al2O3
>.267 B2O3
>.017 Fe2O3
>
>4.324 SiO2
>.017 TiO2
>
>9.7 Ratio
>65.7 Exp
>
>Comments:
>-----------------------------------
>Calculations by GlazeMasterT
>www.masteringglazes.com
>------------------------------------
>
>I hope this helps!
>
>Kathy
>
>______________________________________________________________________________
>Send postings to clayart@lsv.ceramics.org
>
>You may look at the archives for the list or change your subscription
>settings from http://www.ceramics.org/clayart/
>
>Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.
> owner-clay
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
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