G2934 (lower-LOI)
|
Code # G2934Y |
| Materials | Amt |
|---|---|
| Ferro Frit 3249 | 10.000 |
| EPK | 20.500 |
| Wollastonite | 21.500 |
| Talc | 14.000 |
| Nepheline Syenite | 10.500 |
| Silica | 13.000 |
| Calcined Kaolin | 10.500 |
Total:100.00
Auto Unity Formula
|
Si:Al: 6.1:1 5.8 (Molar:5.6) 3.8 Cost 0.20 per kg |
Notes
*This recipe was made as an alternative to blending G2934 matte and G2926B glossy to tune the degree of matteness (this being equal to about an 85:15 mix of those). Those two recipes do not require Frit 3249, they use the much more common 3134, 3124 and 3195. If you are getting started that approach would likely be better for you.
This is an "MgO matte". High MgO content is a common matting mechanism at cone 10 but also works at cone 6. This recipe has the same chemistry as G2934, however, it sources the MgO from a Ferro frit 3249 and talc rather than from dolomite. This specific frit is the secret to why this glaze works. If you do not have it and do not know how to do the chemistry to substitute another MgO-sourcing frit, then you must use the G2934 recipe.
The use of a frit to source MgO in this recipe produces a much lower LOI (3.8 vs. 13.6), a smoother fired surface and better melt fluidity to host stains (stains look fantastic in this base).
Glazes that have MgO levels, including this one, can have crawling issues with certain stains or opacifier additions, especially inside extreme concave contours (e.g. handle joins). Make sure wet glaze slurry wets all inside angles and is not applied too thick. And make sure the glaze dries quickly (glaze inside and outsides separately if needed to avoid water logging the bisque).
WARNING: Like the original, the degree-of-matteness is very dependent on cooling rate. Fast cooling (e.g. free-fall in a lightly loaded or smaller kiln) produces a silky matte surface. Slower cooling (e.g. a heavily loaded kiln) produces a matter and drier surface (subject to cutlery marking). Test in your circumstances to decide whether to adjust your firing to accommodate this or blend in some glossy G2926B produce the silky surface.
Fusion Frit F-69 can be used instead of Ferro Frit 3249 (actually, it is better). This recipe employs a mix of calcined and raw kaolin to keep the drying shrinkage down (to avoid cracking on drying). If you use pure kaolin it will likely crack during drying. If you do not have calcined kaolin just make your own (bisque fire a container of powder).
This glaze has a very low thermal expansion and will not craze on any common clay body. It accepts stains exceptionally well.
We recommend doing cutlery marking tests on your ware. If they mark, blend in a little transparent glossy glaze (like G2926B). This will compromise the matteness a little but will reduce the marking.
Again, although matte in appearance, this glaze has a high melt fluidity. That means that brush-on colors could bleed.
Because this contains both calcined and raw kaolins you can adjust their ratios to control the compromise between dry hardness and drying shrinkage. If better gelling response to Epsom salts (or other flocculant) is needed trade one or two percent raw kaolin for bentonite (to increase the particle surface area).
1100 water, 1000 powder to get a creamy mix.
Regular 2934 (with dolomite) took more water, about 1300. Nicer surface than G2934, same matteness, better fluidity.
Mixing notes:
Joe: April 29/19 Mixed up a batch and added 10% Mason #6021 Red stain. Final totals were: G2934Y + 10% stain weighed 5045 grams.
Water weighed 5450 grams.
Let the glaze sit for 3 days to saturate before adding final water to bring to an S.G. of 1.43 and viscosity was approx. 12 seconds with Ford Cup. At these quantities, the final ratios would be:
Glaze powder (including stain) 48%
Water 52%
This mixture yielded about 7.3 litres of mixed glaze. This glaze was screened 80 mesh and has no Epsom salts added.
Pictures
G2934Y plus 8% Cerdec orange stain on Polar Ice, P300
The stain is #239616 encapsulated. The silky surface is stunning. The color is brighter on whiter porcelains.
G2934Y vs. G2934 melt flow balls
10 gram balls were melted down onto these tiles at cone 5.5.
On darker clay bodies the glaze is translucent. For white on this type of clay body a zircopax addition would be needed.
G2934Y vs G2934 melt flow test
The difference is quite amazing. The chemistry is the same. But the MgO is much more readily released from its source materials in the Y version. Also, even thought the melt is more fluid, it is still just as matte. Part of the reason for the extra fluidity could be the much lower entrained micro-bubble population in the Y (these possibly impeding the flow of the dolomite version on the left).
G2934Y matte with Cerdec red, orange stains
8% stain in each. Cone 6. Drop and hold firing. The surface quality is truly stunning!
G2934Y matte on M370 - cup
Surface very pleasant and finer than the standard G2934.
G2934 (left) vs G2934Y (right) at cone 6
G2934Y with brushwork decoration - By Ingeborg Koot
It is not bleeding significantly because the glaze has not been applied too thick.
G2934Y, G2926B, G3806N on L4202
Cone 6, slow cool. Sitting for 3 weeks.
No apparent crazing.
G2934Y, G2926B, G3806N on L4201
Cone 6 slow cool. Sitting for about 3 weeks.
G2926B is crazing.
G2934Y, G2926B, G3806N on L4200
Cone 6 slow cool. Sitting for 3 weeks.
G2926B has crazed.
G2926B, G2934Y on L4199
Cone 6 slow cool. Sitting for 3 weeks.
G2926B has crazed.
G2934Y, G2926B, G3806N on L4198
Cone 6. Slow cool. Sitting for 3 weeks.
G2926B is crazing.
G2934Y, G2926B, G3806N on L4197
Slow cool. Cone 6. Sitting for three weeks.
No apparent crazing.
Typecodes
C6-Cone 6 Glazes
Variations
-6600 - Black
16 - Yellow
1680 dry and 1400 water produced SG of 1.44. Pretty thick, added a little darvan. Nov. 22/19: Joe made up a 500 gram batch of this glaze. 500 gms. powder 520 gms. water. S.G. checked 3 days lat
239616 - Orange
Cerdec stain. Required no Epsom salts at 1.43 SG. Joe: Aug.2/18 Made a batch of this glaze: Total Powder 3400 grams Total Water 4000 grams S.G via Viscometer 1.417 Viscosity via Ford Cup 12
4 - Overglaze Blue
Test this as a brush-on color for using over G2934Y. We should demonstrate to customers how to fine tune the melt fluidity of an overglaze color and how to mix it with gum to make it paintable.
6000 - Shell Pink
Joe: Aug.8/18 made a batch using same percentages as when I made a batch of the Orange version on Aug.2/18. Total Powder: 2500 grams Water: 2946 grams. S.G. vis Viscometer was 1.401 Viscosity Ford
6213 - Hemlock Green
A little dark. Very intense. Mixed 110 water to 100 dry (3575/3250) to get 1.43 SG.
6304 - Purple
6364 - Baby Blue
3380 powder, 2800 water. 1.43 SG. Worked perfectly. Joe: I think water and powder quantities should be reversed as below percentages? Joe: July 21/21 Made a 5000 gram batch of base powder and ad
6700 - White
Pink - Mason 6020
XML (to paste into Insight)
<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="G2934 (lower-LOI)" id="113976" key="YpiKEKfm" date="2023-11-01" typecodes="C6" codenum="G2934Y" picturebasename=""> <recipelines> <recipeline material="Ferro Frit 3249" amount="10.000" tolerance=""/> <recipeline material="EPK" amount="20.500" tolerance=""/> <recipeline material="Wollastonite" amount="21.500" tolerance=""/> <recipeline material="Talc" amount="14.000" tolerance=""/> <recipeline material="Nepheline Syenite" amount="10.500" tolerance=""/> <recipeline material="Silica" amount="13.000" tolerance=""/> <recipeline material="Calcined Kaolin" amount="10.500" tolerance=""/> </recipelines> </recipe> </recipes>
Born: 2014-03-21, Modified: 2023-11-01 04:47:03
G2934Y Turquoise - Fusion F-69
|
Code # G2934Y |
Notes
*This uses both Fusion Frit F-69 and 45micron silica.
Pictures
G2934Y Turquoise blue , Ferro (left) vs Fusion frit
C6DSSC firing
G2934Y Turquoise on M370
Surface quality is slightly different than with Ferro Frit. Not quite as rich. Perhaps 1% more stain is needed.
G2934Y Turquoise test on Polar Ice
Employ Fusion frit F-69. C6DSSC firing. Glaze surface is a little too matte, not quite as bright as normal. Will try quick cool.
Untitled
G2934Y Turquoise using Fusion Frit
Both use the Fusion frit.
Left: slow cooled, right: quick cooled
The fast cooling a much more similar to the normal result.
G2934Y, G2934 85:15 C6DSSC firing
The blue uses Frit F-69. The black is too glossy, the blue is good. It would use perhaps 1% more stain.
XML (to paste into Insight)
Born: 2021-07-26, Modified: 2024-05-30 13:33:38
G2934Y Red Using F-69
|
Code # G2934Z |
| Materials | Amt |
|---|---|
| Fusion Frit F-69 | 10.000 |
| Nepheline Syenite | 10.500 |
| Wollastonite | 21.500 |
| Talc | 14.000 |
| EPK | 20.500 |
| Silica | 13.000 |
| Calcined Kaolin | 10.500 |
| Additions | |
|---|---|
| *Mason 6021 Red Stain | 11.000 |
Total:111.00
Auto Unity Formula
|
Si:Al: 6.2:1 5.7 (Molar:5.6) 3.8 Cost 0.20 per kg |
Notes
Pictures
Typecodes
C6-Cone 6 Glazes
XML (to paste into Insight)
<?xml version="1.0"?> <recipes version="1.0" encoding="UTF-8"> <recipe name="G2934Y Red Using F-69" id="132192" key="wucp1An6" date="2018-12-29" typecodes="C6" codenum="G2934Z" picturebasename=""> <recipelines> <recipeline material="Fusion Frit F-69" amount="10.000" tolerance=""/> <recipeline material="Nepheline Syenite" amount="10.500" tolerance=""/> <recipeline material="Wollastonite" amount="21.500" tolerance=""/> <recipeline material="Talc" amount="14.000" tolerance=""/> <recipeline material="EPK" amount="20.500" tolerance=""/> <recipeline material="Silica" amount="13.000" tolerance=""/> <recipeline material="Calcined Kaolin" amount="10.500" tolerance=""/> <recipeline material="Mason 6021 Red Stain" amount="11.000" added="true"/> </recipelines> </recipe> </recipes>
Born: 2014-03-21, Modified: 2018-12-29 14:54:33
