[docweathers]

Can someone recommend books on Cone 6 glaze chemistry book for both reduction and oxidation. I am willing to wade through a chemistry "tome" if it spells out the cone 6 reduction dance. "Mastering Cone 6 Glazes" seems to focus on oxidation in electric kilns. Since I am using a cone 10 capable gas kiln, I can experiment with both oxidation and reduction. I am used to thinking of cone 10 reduction as where the really cool glazes are found, but I am moving to cone 6. However, I find little about cone 6 reduction. Am I an old curmudgeon who is perseverating on reduction when that is no longer where the gold is found?

Thanks Larry

[Marcia Selsor]

docweathers, on 17 February 2012 - 07:34 PM, said:

Can someone recommend books on Cone 6 glaze chemistry book for both reduction and oxidation. I am willing to wade through a chemistry "tome" if it spells out the cone 6 reduction dance. "Mastering Cone 6 Glazes" seems to focus on oxidation in electric kilns. Since I am using a cone 10 capable gas kiln, I can experiment with both oxidation and reduction. I am used to thinking of cone 10 reduction as where the really cool glazes are found, but I am moving to cone 6. However, I find little about cone 6 reduction. Am I an old curmudgeon who is perseverating on reduction when that is no longer where the gold is found?

Thanks Larry

I just did a workshop on firing cone 6 reduction at Corpus Christi Art Center.I think there is a lot of information on line in Ceramics Art Daily , most notably Articles by John Britt, Rick Malgram and Diana Pancioli. I fired cone six Reduction beginning in the 1980s through 2000 where I was teaching in Montana.
You need less metal oxides in Reduction than Oxidation for coloring. The base glazes can be the same with a soaking of the high temperature to smooth the surface.
Marcia

[docweathers]

Marcia Selsor, on 17 February 2012 - 07:52 PM, said:

docweathers, on 17 February 2012 - 07:34 PM, said:

Can someone recommend books on Cone 6 glaze chemistry book for both reduction and oxidation. I am willing to wade through a chemistry "tome" if it spells out the cone 6 reduction dance. "Mastering Cone 6 Glazes" seems to focus on oxidation in electric kilns. Since I am using a cone 10 capable gas kiln, I can experiment with both oxidation and reduction. I am used to thinking of cone 10 reduction as where the really cool glazes are found, but I am moving to cone 6. However, I find little about cone 6 reduction. Am I an old curmudgeon who is perseverating on reduction when that is no longer where the gold is found?

Thanks Larry

I just did a workshop on firing cone 6 reduction at Corpus Christi Art Center.I think there is a lot of information on line in Ceramics Art Daily , most notably Articles by John Britt, Rick Malgram and Diana Pancioli. I fired cone six. Reduction beginning in the 1980 where I was teaching in Montana.
You need less metal oxides in Reduction than Oxidation for coloring. The base glazes can be the same with a soaking of the high temperature to smooth the surface.
Marcia

Thanks for the leads. .. Maybe I can do one of your workshops some day. Keep me on your list for something happening in the warmer parts of the US, Dec-Feb 2012-13. I am done freezing my butt off during gloomy Spokane winters.

When is you book on Cone 6 glazes coming out?

Thanks Larry

[Marcia Selsor]

Dinah, on 18 February 2012 - 06:44 PM, said:

I would love to build a gas kiln or a wood firing design to get to ^10. In fact, that's my next long range plan. There are neat glazes up there, and wonderful effects. I want it all! I use electric now at ^6 which is good, make my own glazes, which is good and know that my carbon footprint is smaller than it used to be, which is good. But... I'm a little weary of being good. I've just ordered Fred Olsen's current edition on building kilns, keep revisiting Andrew Holden's The Self Reliant Potter, and ordered M Bailey's Oriental Glazes. Well, we all know what this means don't we! Some wonderful nights watching the stars and the pyrometer. Any other tips would be very welcomed.

My cone 6 reductions glazes (glazes I used in Montana for 20 years) are the only cone 6 glazes in Bailey's book on Oriental Glazes.
Marcia

[JBaymore]

Fiber kiln construction postings have been moved to here:

http://ceramicartsda...n-construction/

[docweathers]

Marcia Selsor, on 19 February 2012 - 11:25 AM, said:

Dinah, on 18 February 2012 - 06:44 PM, said:

I would love to build a gas kiln or a wood firing design to get to ^10. In fact, that's my next long range plan. There are neat glazes up there, and wonderful effects. I want it all! I use electric now at ^6 which is good, make my own glazes, which is good and know that my carbon footprint is smaller than it used to be, which is good. But... I'm a little weary of being good. I've just ordered Fred Olsen's current edition on building kilns, keep revisiting Andrew Holden's The Self Reliant Potter, and ordered M Bailey's Oriental Glazes. Well, we all know what this means don't we! Some wonderful nights watching the stars and the pyrometer. Any other tips would be very welcomed.

My cone 6 reductions glazes (glazes I used in Montana for 20 years) are the only cone 6 glazes in Bailey's book on Oriental Glazes.
Marcia

Do you find that cone 6 is like cone 10 in that some of the best color and texture happens in a reduction as opposed to oxidation environment?

Larry

[confused_yet_curious]

Marcia Selsor, on 17 February 2012 - 10:52 PM, said:

docweathers, on 17 February 2012 - 07:34 PM, said:

Can someone recommend books on Cone 6 glaze chemistry book for both reduction and oxidation. I am willing to wade through a chemistry "tome" if it spells out the cone 6 reduction dance. "Mastering Cone 6 Glazes" seems to focus on oxidation in electric kilns. Since I am using a cone 10 capable gas kiln, I can experiment with both oxidation and reduction. I am used to thinking of cone 10 reduction as where the really cool glazes are found, but I am moving to cone 6. However, I find little about cone 6 reduction. Am I an old curmudgeon who is perseverating on reduction when that is no longer where the gold is found?

Thanks Larry

I just did a workshop on firing cone 6 reduction at Corpus Christi Art Center.I think there is a lot of information on line in Ceramics Art Daily , most notably Articles by John Britt, Rick Malgram and Diana Pancioli. I fired cone six Reduction beginning in the 1980 where I was teaching in Montana.
You need less metal oxides in Reduction than Oxidation for coloring. The base glazes can be the same with a soaking of the high temperature to smooth the surface.
Marcia

Forgive me in advance but oxidation is the use of the electric kiln and reduction is te use of the gas kiln?

[JBaymore]

confused_yet_curious, on 21 February 2012 - 12:48 AM, said:

Forgive me in advance but oxidation is the use of the electric kiln and reduction is te use of the gas kiln?

Oxidation is when inside the kiln chamber during a firing there is an excess of oxygen molecules from any that are needed for combustion (if the is actual combustion taking place). This situation can be achieved in a well designed fuel buriing kiln or in an electric kiln. It allows chemical reactions to take place that require the presence of oxygen gas for their completion. For example, the "burning out" of carbon containing compounds in a clay body requires oxygen so that those combustible materials can be given off as CO₂ gas.

Reduction is when inside the kiln chamber during a firing there is the presence of (combustible) gases that are able to remove oxygen from a molecular compound that, in the elevated temperature state, is able to give off an oxygen atom to those gases. An typical example of this would be the changing of red iron oxide, Fe₂O₃ , to the low level reduced state of FeO. "Reduction" is actually a chemisit's term meaning to remove oxygen from a compound. This situation can be achieved in a well designed fuel buriing kiln or in an electric kiln that is specially designed to create reduction.

Sometimes low levels of reduction can be inadvertantly caused in an electric kiln when there is not a sufficient flow of fresh air through the kiln (like that generated with an active local pickup kiln vent) so that the carbonaceous matter that is a contaminent of most raw clays consumes all of the available oxygen in the chamber... and then starts to produce low level amounts of CO (carbon monoxide). This can sometimes happen in a really tightly packed bisque in a kiln with improper venting.

So it is not exactly limited to "electric = oxidation gas = reduction".

best,

......................john

[confused_yet_curious]

Thank you for this information!

JBaymore, on 21 February 2012 - 10:22 AM, said:

confused_yet_curious, on 21 February 2012 - 12:48 AM, said:

Forgive me in advance but oxidation is the use of the electric kiln and reduction is te use of the gas kiln?

Oxidation is when inside the kiln chamber during a firing there is an excess of oxygen molecules from any that are needed for combustion (if the is actual combustion taking place). This situation can be achieved in a well designed fuel buriing kiln or in an electric kiln. It allows chemical reactions to take place that require the presence of oxygen gas for their completion. For example, the "burning out" of carbon containing compounds in a clay body requires oxygen so that those combustible materials can be given off as CO₂ gas.

Reduction is when inside the kiln chamber during a firing there is the presence of (combustible) gases that are able to remove oxygen from a molecular compound that, in the elevated temperature state, is able to give off an oxygen atom to those gases. An typical example of this would be the changing of red iron oxide, Fe₂O₃ , to the low level reduced state of FeO. "Reduction" is actually a chemisit's term meaning to remove oxygen from a compound. This situation can be achieved in a well designed fuel buriing kiln or in an electric kiln that is specially designed to create reduction.

Sometimes low levels of reduction can be inadvertantly caused in an electric kiln when there is not a sufficient flow of fresh air through the kiln (like that generated with an active local pickup kiln vent) so that the carbonaceous matter that is a contaminent of most raw clays consumes all of the available oxygen in the chamber... and then starts to produce low level amounts of CO (carbon monoxide). This can sometimes happen in a really tightly packed bisque in a kiln with improper venting.

So it is not exactly limited to "electric = oxidation gas = reduction".

best,

......................john

[Marcia Selsor]

Larry,
I have been using ^6 oxidation for the past few years and am very happy with all I have learned. I do love firing gas kilns but I am stuck with oxidation in my current situation. I have found beautiful results with firing down techniques in Oxidation. In Cone 6 reduction, I have also found beautiful techniques in firing including the importance of ^09-^04 body reduction which I demonstrated in the firing workshop I taught in January at Corpus Chriti Art center. The people there were amazed at the richness of their clay body compared to what they had been getting without body reduction.
Hope this helps.
Marcia

[Laura A Strike]

I work at our community college. We do redution firing in a gas kiln. Many oxidation glazes work in either environment, but you must test them because they may result in a different color.

A good example is Eggshell which is creamy white with rust specs in oxidation, but changes to a specked rust to green inreduction.

Good luck with experimenting

[confused_yet_curious]

Laura A Strike, on 26 February 2012 - 09:44 PM, said:

I work at our community college. We do redution firing in a gas kiln. Many oxidation glazes work in either environment, but you must test them because they may result in a different color.

A good example is Eggshell which is creamy white with rust specs in oxidation, but changes to a specked rust to green inreduction.

Good luck with experimenting

Hey do you by any chance have the recipe for Eggshell glaze?

[Laura A Strike]

Yes, I will have to look for it. Send it to you by the end of the week.

Anything else?