Mason Stain in base glazes

[Guest]

If I use the basic MC6G base glaze and and add a mason stain what is a good starting point to test how much stain to add? I honestly don't know If I should start with 5% or 50%

I'm considering trying

• #6200 Evergreen
• #6600 Best Black
• #6464 Zirconium

TIA

[Fred Sweet]

RonSa-

For color development in glazes, I start with 1-5% for most Ceramic stains (look at the normal use of color oxides in glazes) for stronger, darker stains. For the lighter colors, I usually start with a range of 1-10%. If you were talking about slips or underglazes, then I would consider starting with a range of 5-20% for darker and 5-35% for lighter stains. For clay body color, I’d start even higher.

Think transparency to opacity based on the amount of “glass” development in the final product.

Just my way of looking at “things clay and glazes.”

Regards,

Fred

[Min]

I use 2 of those stains, depending on how intense you want the colour but around 7-10% of the 6600 works to get black. It's an expensive way to get a black glaze though, the Licorice glaze from the same book using 2 cobalt carb and 9 iron makes a nice solid black. I make a pale yellow with 1 point 25 of 6464. The chrome green stains can be really intense, I would start at 0 point5% and test up to 3 point 5% at the very most.

Easy way to test amounts would be to mix up 100 base plus minimum amount of stain you think you need (like 6 for the 6600) dip a test tile. Then add another 1 gram of 6600 and dip another tile and so on up to say 10 for the 6600. Not super accurate as the glaze quantity decreases with each subsequent dip but it will get you close. For strong stains or very pale tints go up by fractions of a percentage.

[neilestrick]

I've been running tests of about 15 different mason stains in a clear base every day for the last 3 weeks. My first round was 4% of the warm colors, 2% of the cold colors. It was a good starting point and gave me many nice results. I've also been blending colors, for instance trying to tone down a very bright yellow, and as little as 0.2% of some browns will have a noticeable effect. A lot will depend on how your base glaze responds to colorants, though.

[Roberta12]

I just used 4% praseodymium (spelling!) and 4% tangerine in a base, trying for a creamsicle orange.  I should have used less of the yellow.  Go with the lower percentages, the stains are strong. 

 

Roberta

[Guest]

Thanks All

[Guest]

20 hours ago, Min said:

around 7-10% of the 6600 works to get black. It's an expensive way to get a black glaze though, the Licorice glaze from the same book using 2 cobalt carb and 9 iron makes a nice solid black

One of the clay bodies I use has a problem with crazing with glazes in the upper 6.xx COE.
JB's Licorice is 7.11.  MC6G base with #6600 is 6.14 when I change out Custer feldspar with Minspar.
Yes the stain is more expensive, close to twice the cost... its just from experience I lack the confidence that a COE of 7.11 would work on this clay

Does mason stains change the COE any?

Here's the modified MC6G base with #6600 I'm considering

Ferro Frit 3134    29
Silica                           26
EP Kaolin                 22
Minspar 200            9
Talc                              10
Wollastonite            4
Bentonite                   2
Mason Stain             7-10 (#6600)

18 hours ago, neilestrick said:

A lot will depend on how your base glaze responds to colorants, though.

I guess I need to find out

[Min]

1 hour ago, RonSa said:

One of the clay bodies I use has a problem with crazing with glazes in the upper 6.xx COE.
JB's Licorice is 7.11.  MC6G base with #6600 is 6.14 when I change out Custer feldspar with Minspar.
Yes the stain is more expensive, close to twice the cost... its just from experience I lack the confidence that a COE of 7.11 would work on this clay

Does mason stains change the COE any?

Hi Ron,

The large amount of RIO in the Licorice Black glaze recipe has an effect to reduce crazing, as does the cobalt. I would suggest not including colouring oxides in your COE figures, click "phantom" with your Insight program next to them so they are not included in the math and see what the COE comes out as. Yup stains change the COE, 6600 has cobalt, chrome, iron and nickel, thing is we can't find out the proportions of each so back to trial and error testing. What you don't want to do is put a high expansion glaze on the outside of a pot and a low one on the inside (or vice versa) as this can lead to dunting. 

[Guest]

39 minutes ago, Min said:

I would suggest not including colouring oxides in your COE figures, click "phantom" with your Insight program next to them so they are not included in the math and see what the COE comes out as

It comes out to 6.69, ok, I'll give it a try. Thanks