Ravenscrag Slip cone 6 base glaze using various frits

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See Also:
Cone 6 white matte and glossy that do not crawl


Ravenscrag Original cone 6 base glaze

Code #

G2936C

Materials Amt
Ravenscrag Slip 50.000
Ferro Frit 3134 20.000
Ravenscrag Slip 1000F Roast 30.000

Total:100.00

Auto Unity Formula

CaO 0.68
MgO 0.11
K2O 0.08
Na2O 0.12
(KNaO) 0.21
TiO2 0.01
B2O3 0.21
Al2O3 0.33
SiO2 3.13
Fe2O3 0.01

Ratios

Si:Al: 9.5:1
SiB:Al: 10.1:1
R2O:RO: 0.2:0.8

Expansion

7.0 (Molar:6.8)

LOI

5.3

Notes

*Also known as GR6-A at PlainsmanClays.com.

It melts, at 100%, to a silky transparent at cone 10R. A 20% frit addition melts it for use at cone 6 oxidation.

A 2% addition of Zircopax can be helpful as a fining agent to reduce entrained bubbles if they are an issue. For white increase the Zircopax to 10%.

Traditionally we have used Ferro Frit 3134 (experiments with other frits not not improved it).

Ravenscrag Slip suspends well in water and normally one can just mix it 80:20 with a frit. But we have found that this can crack during drying. Thus we use a 50:30 mix of raw:roast material (more information on the page at PlainsmanClays.com). However, if you wish to add some CMC Gum, then the 50:30 mix is not needed (although it will dry slower and be more challenging to get an even layer (without drips).

This can be used as a base recipe. Add opacifiers, colorants and variegators to produce all manner of visual effects. This differs from a regular clear glaze made from industrial minerals in that the fired appearance is more organic, less sterile.

Pictures

GR6-A Ravenscrag Clear cone 6

On M370, M340 and M390.

GR6-A Ravenscrag white cone 6

Adds 10% zirocpax to the GR6-A recipe.
On M370, M340 and M390.

G2936 vs GR6-A - Cone 6 on M370

G2936 vs GR6-A - Cone 6 on M370

On M370

GR6-A on M390 cone 6

Alternate Code Number:GR6-A

Variations

1 - Pink

XML (to paste into Insight)

<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="Ravenscrag Original cone 6 base glaze" id="56548" key="EpB7byWw" date="2023-08-28" codenum="G2936C"> <recipelines> <recipeline material="Ravenscrag Slip" amount="50.000" tolerance=""/> <recipeline material="Ferro Frit 3134" amount="20.000" tolerance=""/> <recipeline material="Ravenscrag Slip 1000F Roast" amount="30.000" tolerance=""/> </recipelines> </recipe> </recipes>

Born: 2014-03-03, Modified: 2023-08-28 17:53:01

Ravenscrag with 20% Frit 3249

Code #

G2936

Materials Amt
Ravenscrag Slip 80.000
Frit 3249 20.000

Total:100.00

Auto Unity Formula

CaO 0.55
MgO 0.33
K2O 0.09
Na2O 0.02
(KNaO) 0.11
TiO2 0.01
B2O3 0.29
Al2O3 0.44
SiO2 3.39
Fe2O3 0.01

Ratios

Si:Al: 7.7:1
SiB:Al: 8.4:1
R2O:RO: 0.1:0.9

Expansion

5.9 (Molar:5.6)

LOI

7.0

Cost

0.00 per kg

Notes

*This frit appears to produce slightly better results than Frit 3134 (less dimples, surface defects). We used the PLC6DS firing schedule.

Since this is not a roast:raw mix it would be best to use an appropriate CMC gum solution:water mixture.

Pictures

G2936A - Ravenscrag with 20% Frit 3249

Cone 6 PLC6DS firing. Excellent results, no pinholes, bubbles as can happen with frit 3134.

G2936 clear vs G2936A white - Cone 6 PLC6DS firing

G2936 vs G2936A - Cone 6 PLC6DS firing

G2936+Zr at cone 5

P6954 at cone 5 - G3936 inside glaze crazed

Slow cool firing
Outsides: G3903 (AltaSlip + Frit FZ16)
Insides:
G2936 Ravenscrag with Ferro 3249, pleasant matte, quite transparent (crazed over time, very strange, likely needs cone 6).

G2926SX: Needs to be a little thicker application.

G2936 at cone 3

XML (to paste into Insight)

<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="Ravenscrag with 20% Frit 3249" id="57080" key="41yriZDJ" date="2021-12-11" codenum="G2936" picturebasename=""> <recipelines> <recipeline material="Ravenscrag Slip" amount="80.000" tolerance=""/> <recipeline material="Frit 3249" amount="20.000" tolerance=""/> </recipelines> </recipe> </recipes>

Born: 2014-03-17, Modified: 2021-12-11 18:11:16

Ravenscrag +20% Frit 3249 +Zircon

Code #

G2936A

Materials Amt
Ravenscrag Slip 80.000
Ferro Frit 3249 20.000
Additions
Zircopax 10.000

Total:110.00

Auto Unity Formula

CaO 0.55
MgO 0.33
K2O 0.09
Na2O 0.02
(KNaO) 0.11
TiO2 0.01
B2O3 0.29
Al2O3 0.44
SiO2 3.58
Fe2O3 0.01
ZrO2 0.19

Ratios

Si:Al: 8.1:1
SiB:Al: 8.8:1
R2O:RO: 0.1:0.9

Expansion

6.1 (Molar:5.7)

LOI

7.0

Notes

*We also incorporated some gum solution, this worked well to eliminate cracking on drying (thus no roast:raw mix was needed).

The white variation of the GR6-A glaze can be quite striking (compared to the "toilet bowl" appearances of other whites. This version is likely to produce a more defect-free surface. And this frit, although more expensive, reduced the thermal expansion, that should eliminate any issues with crazing on just about any clay body.

Batch Ticket Notes

Add 0.35% CMC powder to the glaze recipe and mix 110 powder to each 100 water.

Pictures

G2936A vs G2934YZ fired to cone 4

G2936 clear vs G2936A white - Cone 6 PLC6DS firing

G2936A - Cone 6 PLC6DS firing

On M370, M340, M390 - Excellent results on all of them!

G2936 vs G2936A - Cone 6 PLC6DS firing

Tin opacified g2926b vs g2936a on black engobe

G2936 at cone 02

XML (to paste into Insight)

<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="Ravenscrag +20% Frit 3249 +Zircon" id="205853" key="BHQRPJm6" date="2022-09-09" codenum="G2936A" picturebasename=""> <recipelines> <recipeline material="Ravenscrag Slip" amount="80.000" tolerance=""/> <recipeline material="Ferro Frit 3249" amount="20.000" tolerance=""/> <recipeline material="Zircopax" amount="10.000" added="true"/> </recipelines> </recipe> </recipes>

Born: 2014-03-17, Modified: 2022-09-09 13:08:01

Ravenscrag Opaque Ivory White

Code #

G2936B

Materials Amt
Ravenscrag Slip 80.000
Ferro Frit 3249 20.000
Additions
Zircopax 5.000
Tin Oxide 3.000

Total:108.00

Auto Unity Formula + Analysis

BaO 0.01 0.22%
CaO 0.55 8.08%
MgO 0.33 3.50%
K2O 0.09 2.21%
Na2O 0.02 0.37%
(KNaO) 0.11
TiO2 0.01 0.29%
B2O3 0.29 5.32%
Al2O3 0.44 11.73%
SiO2 3.48 54.78%
Fe2O3 0.01 0.59%
SnO2 0.07 2.76%
ZrO2 0.10 3.09%

Ratios

Si:Al: 7.9:1
SiB:Al: 8.6:1
R2O:RO: 0.1:0.9

Expansion

5.9 (Molar:5.6)

LOI

7.0

Notes

*This modifies G2936A to whiten using a mix of tin oxide and zircopax to minimize crawling.

At 1.6 specific gravity with ~.25% CMC gum this produces a good base coat dipping glaze.

For a 500ml jar of brushing glaze we blender mix 340 powder, 440 water, 5 CMC gum and 3.5 Veegum.

Batch Ticket Notes

Added 0.35% CMC powder to the glaze recipe and mix 110 powder to each 100 water. Much too watery, evaporated down to 1.6SG.

Pictures

G2936B RavenWhite vs G2926B white

G2926B white vs G2936B RavenWhite

G2926B white vs G2936B RavenWhite

G2936B RavenWhite with G3948C over it at cone 6

XML (to paste into Insight)

<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="Ravenscrag Opaque Ivory White" id="224213" key="xod46oLF" date="2022-12-25" codenum="G2936B" picturebasename=""> <recipelines> <recipeline material="Ravenscrag Slip" amount="80.000" tolerance=""/> <recipeline material="Ferro Frit 3249" amount="20.000" tolerance=""/> <recipeline material="Zircopax" amount="5.000" added="true"/> <recipeline material="Tin Oxide" amount="3.000" added="true"/> </recipelines> </recipe> </recipes>

Born: 2014-03-17, Modified: 2022-12-25 22:34:25