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copper reds

updated tue 1 feb 11

 

Lawrence L. Anderson on sat 25 jan 97

Erin,
Having worked with Dr. Herbert H. during those years he wrote that, I
once asked him what he ment by that particular statement. As near as I
can remember, he didn't mean that you couldn't use the copper glaze later
or within the next week, but that it did have a shelf life. I believe
his exact words were, you'd better use it up within the first two weeks
for the "best results".

JaneDoeVII on mon 18 aug 97

Am seeking any information on firing schedules for Copper Reds using an
oxy probe and/or if anyone knows the firing schedule that Tom Coleman uses
for his reds.

Thank you,
Angel DiCosola
JaneDoeVII@AOL.com

Chris Trabka on sat 23 aug 97

JaneDoeVII wrote:
>
> ----------------------------Original message----------------------------
> Am seeking any information on firing schedules for Copper Reds using an
> oxy probe and/or if anyone knows the firing schedule that Tom Coleman uses
> for his reds.
>
> Thank you,
> Angel DiCosola
> JaneDoeVII@AOL.com
I have been getting consistent copper reds for a number of years now. I
found several things in research I did.

1. The glaze must be applied thickly (about the consistency of pancake
batter - which leads to the running problems)
2. Reduction must begin at ^06 (this is the approximate that carbon
becomes a gas). You want to remove all the oxygen from the oxides in the
glaze but you do not want to force carbon into the ware; a subtle
balance.
3. Reduction must be consistent through ^6.
4. "Heavy Reduction" after ^6 does not affect the glaze.

I generally fire to cone 10. It takes about 8 hours to reach ^10 and
about 24 to 36 hours to cool off.

Chris

Mark Issenberg on mon 17 nov 97

Howdy All: I was reading Nils Lou book about firing and he had put
something in there about putting a burner on that will smoke when the
kiln is about 1200 F on its cooling cycle. If any of you have done this,
please let me know and would you pull the damper when you do this?

Also, does anyone know where James Lawton is? Still hot in Miami.

Mark in Miami

Talbott on mon 17 nov 97

Mark... Called..Post fire reduction... I have tried it and I don't do it
anymore... may get a little color but overall it makes the glazes dull and
not bright and shiney.. So I don't post fire reduce anymore... Marshall

PS.. WE Got 10" of new snow over the weekend.. Most snow for this time of
year in 99 years... El Nino?

>----------------------------Original message----------------------------
>Howdy All: I was reading Nils Lou book about firing and he had put
>something in there about putting a burner on that will smoke when the
>kiln is about 1200 F on its cooling cycle. If any of you have done this,
>please let me know and would you pull the damper when you do this?
>
>Also, does anyone know where James Lawton is? Still hot in Miami.
>
>Mark in Miami

101 CLAYART MUGS... A TRAVELING EXHIBIT
2ND ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1998)
E-MAIL ME FOR AN APPLICATION
http://fmc.utm.edu/~dmcbeth/cag/naples.htm

Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
Clayarters' Live Chat Room, Fri & Sat Nites at 10 PM EDT & Sun at 1 PM EDT
http://webchat12.wbs.net/webchat3.so?Room=PRIVATE_Clayarters
---------------------------------------------------------------------

Sheryl VanVleck on tue 18 nov 97

In a message dated 97-11-17 12:17:18 EST, you write:

<< Also, does anyone know where James Lawton is? >>

in 1993, James Lawton was teaching at The School of the Art
Institute of Chicago. He may still be there. I'd be interested to
know also as I have a tile that belongs to him.

Sheryl A. VanVleck
savanvleck@aol.com
Evansville, WY where the sunrise was gorgeous, temps
are cooling down and, I'm told, the wind will help our wood firing
this week

Vince Pitelka on tue 18 nov 97

Hey, Mark, what gives here? I have sent you three email messages over the
last six weeks, and no response at all. Is there something wrong with the
phone lines between here and Miami? I hope I have not done anything to
upset or offend you. Please let me know what's going on.

And regarding copper reds, we get the best results with a heavy body
reduction at cone 08, partial reduction until cone 9 starts to bend, neutral
to cone ten, and fifteen minute oxidation cleanup. I have never heard of
anyone using reduction cooling for copper reds, but it is an intriguing idea.
- Vince

Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166

DIANA PANCIOLI, ASSOC. PROF. on wed 19 nov 97

Reducing at 1200F on the way down is also called striking the kiln. It is
especially effective with low temp glazes. I think Jun Kaneko gets his
pink/red striped color effects by striking the kiln. The 1200 degree temp
is used because that is just before the glaze cools, and when it
cools, it holds the reduction. Striking is also used to produce in-glaze
lusters.

DP

On Mon, 17 Nov 1997, Talbott wrote:

> ----------------------------Original message----------------------------
> Mark... Called..Post fire reduction... I have tried it and I don't do it
> anymore... may get a little color but overall it makes the glazes dull and
> not bright and shiney.. So I don't post fire reduce anymore... Marshall
>
> PS.. WE Got 10" of new snow over the weekend.. Most snow for this time of
> year in 99 years... El Nino?
>
> >----------------------------Original message----------------------------
> >Howdy All: I was reading Nils Lou book about firing and he had put
> >something in there about putting a burner on that will smoke when the
> >kiln is about 1200 F on its cooling cycle. If any of you have done this,
> >please let me know and would you pull the damper when you do this?
> >
> >Also, does anyone know where James Lawton is? Still hot in Miami.
> >
> >Mark in Miami
>
> 101 CLAYART MUGS... A TRAVELING EXHIBIT
> 2ND ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1998)
> E-MAIL ME FOR AN APPLICATION
> http://fmc.utm.edu/~dmcbeth/cag/naples.htm
>
> Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
> Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
> Clayarters' Live Chat Room, Fri & Sat Nites at 10 PM EDT & Sun at 1 PM EDT
> http://webchat12.wbs.net/webchat3.so?Room=PRIVATE_Clayarters
> ---------------------------------------------------------------------
>

Ron or Sue Corl on thu 20 nov 97


Linda,

I have always understood that 2 different events happen in a reduction
firing: body red. then glaze red. I am a huge fan of real life as
opposed to theory, and I believe your results but how does the color
formation happen below the melting temperatures of the glaze? How is the
glaze 'starved of oxygen' when it is not hot enough to change it's
molecular structure?

Thanks,

Ron
Big Baby Head

Linda Arbuckle on thu 20 nov 97

Date: Tue, 18 Nov 1997 08:01:06 EST
From: Vince Pitelka
Subject: Re: Copper Reds

----------------------------Original message----------------------------

> Date: Tue, 18 Nov 1997 08:01:06 EST
> From: Vince Pitelka
> Subject: Re: Copper Reds
>
> ----------------------------Original
> message----------------------------
>
> And regarding copper reds, we get the best results with a heavy body
> reduction at cone 08, partial reduction until cone 9 starts to bend,
> neutral
> to cone ten, and fifteen minute oxidation cleanup. I have never heard
> of
> anyone using reduction cooling for copper reds, but it is an
> intriguing idea.
> - Vince
>
> --

Pete Pinnell gave an excellent workshop at ClayFactory in Tampa several
years back, and fired a bunch of copper reds at U to Tampa. He
demonstrated that his method of early reduction (beginning at cone 010),
then neutral up to almost temperature followed by at least 20 minutes of
oxidizing produces beautiful copper reds. What I was taught to do, a
"glaze reduction" at cone 9 or 10, didn't matter and just wasted fuel.

At UF we have a small gas test kiln, so that I could try this at home
cautiously and see if I could get the same results as a "trained
professional" in copper reds. Worked fine. As Pete pointed out, thick
enough glaze application and a good glaze are also needed, but not a
second reduction.

Linda Arbuckle
Associate Professor, Graduate Coordinator
University of Florida, Box 115801, Gainesville, FL 32611-5801
e-mail:arbuck@ufl.edu (Note: this is a new e-mail address)

John Tilton on sat 16 may 98

Just a quick note; my copper reds are always best in rainy weather--the
rainier the better.

John


--
John Tilton
16211 NW 88th Terrace
Alachua, Fl. 32615
904-462-3762
http://www.tiltonpottery.com

Steve Howkins on sun 17 may 98

Re the copper reds are better in the rain.. I have come across somene who
stood for hours squirting water into a gas kiln to make it reduce more
completly.

Regards Steve Howkins

howkins@netspace.net.au

Lee Marshall on thu 7 oct 99

David
thanks for a great article in ceramics monthly. i have just mixed up a new
batch of my copper red glaze and reformulated it to remove the barium and
zinc. can't wait to open the kiln. i've wanted to get rid of the barium for
years but fear of testing kept it in there. it just seemed like i was always
too rushed to do the testing. thanksTHANKS!!!thanks
lee
LMarsh1220@aol.com

Lorraine Pierce on thu 7 oct 99

David, that was a very impressive bit of research in Ceramics Monthly on copper
reds! Wish I had had it when I had my gas kiln and was doing them...but I think
the barium and zinc findings would be applicable in other glazes also.
Question...under the picture of your two mugs (loved 'em) the notation
stated..."yellow inclusion stain". I am not familiar with the term 'inclusion
stain', tho I realize any water stain with colorants would be inclusive...is
that it?Or does it refer to a fritted stain? Again, thanks for a fascinating
article. Lori in New Port Richey Fl.

Lee Marshall wrote:

> ----------------------------Original message----------------------------
> David
> thanks for a great article in ceramics monthly. i have just mixed up a new
> batch of my copper red glaze and reformulated it to remove the barium and
> zinc. can't wait to open the kiln. i've wanted to get rid of the barium for
> years but fear of testing kept it in there. it just seemed like i was always
> too rushed to do the testing. thanksTHANKS!!!thanks
> lee
> LMarsh1220@aol.com

Tasha Olive on fri 8 oct 99

Hello all, this thread caught my attention. Mind telling us which issue of
CM? If it was the most recent guess I didn't cover thoroughly enough. Tasha
-----Original Message-----
From: Lorraine Pierce
To: CLAYART@LSV.UKY.EDU
Date: Thursday, October 07, 1999 5:21 PM
Subject: Re: copper reds


>----------------------------Original message----------------------------
>David, that was a very impressive bit of research in Ceramics Monthly on
copper
>reds! Wish I had had it when I had my gas kiln and was doing them...but I
think
>the barium and zinc findings would be applicable in other glazes also.
>Question...under the picture of your two mugs (loved 'em) the notation
>stated..."yellow inclusion stain". I am not familiar with the term
'inclusion
>stain', tho I realize any water stain with colorants would be
inclusive...is
>that it?Or does it refer to a fritted stain? Again, thanks for a
fascinating
>article. Lori in New Port Richey Fl.
>
>Lee Marshall wrote:
>
>> ----------------------------Original message----------------------------
>> David
>> thanks for a great article in ceramics monthly. i have just mixed up a
new
>> batch of my copper red glaze and reformulated it to remove the barium and
>> zinc. can't wait to open the kiln. i've wanted to get rid of the barium
for
>> years but fear of testing kept it in there. it just seemed like i was
always
>> too rushed to do the testing. thanksTHANKS!!!thanks
>> lee
>> LMarsh1220@aol.com

Wynne Wilbur on mon 3 mar 03


Paul,

Pete Pinnell had a great article (two articles) in Clay Times a few years
ago on firing copper reds. I'm sorry I can't tell you which issue but it
shouldn't be too hard to find. In it, he says not to fire them too high
(cone 9 is good) although the caution is for running not because it changes
the color. He also says don't over reduce after cone 5 and he gets the best
reds in a very light reduction from cone 5-9 with a 30-60 oxidation soak at
the end. He talks about getting blues by using bone ash or titanium or
adding more silica so perhaps your materials have changed a bit too. One of
the glaze recipes he shares in the article indicates that the presence of
boron in the glaze and a slow cool will turn blue.

There's lots more in the article - hope you can find a copy.

Wynne Wilbur

Assistant Professor of Art
Truman State University
Division of Fine Arts
100 East Normal
Kirksville, Missouri 63501
660 785-4435
wwilbur@truman.edu

RJ Shulenburg on sat 28 may 05


After having several successful firings of copper reds mixed with other
glazes I decided to try a whole kiln load of reds. (Bailey 18/12 natural
gas) Peeked in the kiln this morning and everything that I could see was
white. I did not fire down at 1750F. So my question is: If I refire
oxidation to 1750F (kiln is 600F now) and hold there for an hour what are
the odds of getting reds?

Ronda Borberg-Shulenburg
Virginia Beach

David Beumee on sun 29 may 05


Ronda wrote,
" If I refire
> oxidation to 1750F (kiln is 600F now) and hold there for an hour what are
> the odds of getting reds?"

From the story that Pete Pinnell tells, I'd say the odds are very good.

David Beumee
Lafayette, CO














-------------- Original message ----------------------
From: RJ Shulenburg
> After having several successful firings of copper reds mixed with other
> glazes I decided to try a whole kiln load of reds. (Bailey 18/12 natural
> gas) Peeked in the kiln this morning and everything that I could see was
> white. I did not fire down at 1750F. So my question is: If I refire
> oxidation to 1750F (kiln is 600F now) and hold there for an hour what are
> the odds of getting reds?
>
> Ronda Borberg-Shulenburg
> Virginia Beach
>
> ______________________________________________________________________________
> 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.

RJ Shulenburg on wed 8 jun 05


It didn't work. Most likely the copper burned out in the initial
firing...sigh...back to glaze tests. Ronda

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of David Beumee
Sent: Sunday, May 29, 2005 10:33 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Copper Reds

Ronda wrote,
" If I refire
> oxidation to 1750F (kiln is 600F now) and hold there for an hour what
> are the odds of getting reds?"

From the story that Pete Pinnell tells, I'd say the odds are very good.

David Beumee
Lafayette, CO














-------------- Original message ----------------------
From: RJ Shulenburg
> After having several successful firings of copper reds mixed with
> other glazes I decided to try a whole kiln load of reds. (Bailey 18/12
> natural
> gas) Peeked in the kiln this morning and everything that I could see
> was white. I did not fire down at 1750F. So my question is: If I
> refire oxidation to 1750F (kiln is 600F now) and hold there for an
> hour what are the odds of getting reds?
>
> Ronda Borberg-Shulenburg
> Virginia Beach
>
> ______________________________________________________________________
> ________ 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.

____________________________________________________________________________
__
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.

Lesley Anton on thu 30 aug 07


Thanks to everyone for some fine advise. I wlll give it a slower
cool next time. This most recent firing though, I cooled to 1900,
then let it sit there for 1 1/2 hours and then shut it down. The
result was light red, with nice red in the creases of the pot, and
almost white on the upper surface - I think the glaze was too thin
( I counted to 2 in the glaze bucket). I'm going to refire those,
dipping them once more when they're hot, but I have some more that I
still have to fire, that I put a thicker coat (counted to 3.5 in the
glaze bucket) on and will try to soak from 2000 to 1800 for 4 hrs,
this time. Then shut it down.

I get so paranoid about dripping that I under do the glaze coverage
sometimes.
I also sometimes get started too late, then end up having to pull
3am nights - argh.

Wish me luck.

Lesley Anton Handmade Ceramic Lighting
323.934.3463
www.lesleyanton.com

Lesley Anton on thu 30 aug 07


Hi there,
I have a cone 10, copper red question here. I have a 9 cubic foot
fiber updraft kiln. I am wondering if any of you have developed any
tricks to getting a consistant red with this kind of kiln.

Mel Jacobson - I happened upon a posting from long ago that you had
said "at the end of the firing, pull the peeps, and turn off the
burners for about 10 minutes until the temp drops to 1900, then close
it back up, and hold there for an hour and a half. Then close it up
tight."

I have had ok results with this, mainly probably due to thickness of
glaze, but when I go thicker, I get some runs at the bottom. But not
ever really rich reds - not like the stuff that comes out of my
buddies brick kiln. Any reason for this?

Any response would be welcomed.

Lesley Anton


Lesley Anton Handmade Ceramic Lighting
www.lesleyanton.com

Dannon Rhudy on thu 30 aug 07


Lesley said:

> I have had ok results with this, mainly probably due to thickness of
> glaze, but when I go thicker, I get some runs at the bottom. But not
> ever really rich reds - not like the stuff that comes out of my
> buddies brick kiln. Any reason for this?

The best thing you can do for good, consistent copper reds
is to read Pete Pinnell's series of copper red articles in Clay
Times. From three years or more back, can't remember the
dates but Clay Times can and will tell you.

The things to think about are these: a copper red glaze
that is stable enough to go on fairly thick without running
(Pete's Cranberry and Pete's Orange Red are both good).
The red develops in the middle of the glaze, with a layer of
clear against the clay and a layer of clear on top. See
cross sections in Tichane's "Copper Red Glazes". Begin
reduction early - I start at cone 010 for reds and shinos.

Then, copper red colors develop DURING COOLING, so
you need a long cooling cycle. It does not matter
whether your kiln is brick or fiber - but you must adjust
your firing so that the reds have time to develop during
cooling. If you cool too fast, reds will be spotty,
literally. Re-light and bring the temp down slow, if you
need to do that. Sometimes fiber kilns cool more rapidly.

Repeat: stable glazes, so they don't run when thick; early reduction
(doesn't need to be heavy); and slow cooling.

A bit of practice, and you'll get what you want.

regards

Dannon Rhudy

Hank Murrow on thu 30 aug 07


Dear Lesley;

I would add that it is a good idea to set up a series of draw trials
to determine when the best color appears. Pull a draw trial every 50
degrees F during cooling and note when the best color appears. the
next time you fire, re-light the kiln around that temperature and set
it up so that it is in oxidation or neutral and holding steady
temperature. Try a soak of four hours at first, adjusting as needed.
Cool normally after the soak.

This is the procedure I used to find the best point in the cooling to
achieve my bloody shinos....... very effective. Worked also in
developing my copper yellow series.

Cheers! Hank

http://www.murrow.biz/hank


On Aug 30, 2007, at 3:43 PM, Dannon Rhudy wrote:

> Lesley said:
>
>> I have had ok results with this, mainly probably due to thickness of
>> glaze, but when I go thicker, I get some runs at the bottom. But not
>> ever really rich reds - not like the stuff that comes out of my
>> buddies brick kiln. Any reason for this?
>
> The best thing you can do for good, consistent copper reds
> is to read Pete Pinnell's series of copper red articles in Clay
> Times. From three years or more back, can't remember the
> dates but Clay Times can and will tell you.
>
> The things to think about are these: a copper red glaze
> that is stable enough to go on fairly thick without running
> (Pete's Cranberry and Pete's Orange Red are both good).
> The red develops in the middle of the glaze, with a layer of
> clear against the clay and a layer of clear on top. See
> cross sections in Tichane's "Copper Red Glazes". Begin
> reduction early - I start at cone 010 for reds and shinos.
>
> Then, copper red colors develop DURING COOLING, so
> you need a long cooling cycle. It does not matter
> whether your kiln is brick or fiber - but you must adjust
> your firing so that the reds have time to develop during
> cooling. If you cool too fast, reds will be spotty,
> literally. Re-light and bring the temp down slow, if you
> need to do that. Sometimes fiber kilns cool more rapidly.
>
> Repeat: stable glazes, so they don't run when thick; early reduction
> (doesn't need to be heavy); and slow cooling.
>
> A bit of practice, and you'll get what you want.
>
> regards
>
> Dannon Rhudy

KATHI LESUEUR on thu 30 aug 07


On Aug 30, 2007, at 1:04 PM, Lesley Anton wrote:

> Hi there,
> I have a cone 10, copper red question here. I have a 9 cubic foot
> fiber updraft kiln. I am wondering if any of you have developed any
> tricks to getting a consistant red with this kind of kiln....
>
> I have had ok results with this, mainly probably due to thickness of
> glaze, but when I go thicker, I get some runs at the bottom. But not
> ever really rich reds - not like the stuff that comes out of my
> buddies brick kiln. Any reason for this?>>

I've found that two things greatly affect my copper reds-location in
the kiln and thickness of the glaze. My kiln is two shelves deep. I
get consistent red only in the front and only in the upper three-
quarters. There's no sense to put it anywhere else since the chances
of it working are about 50%. I find that good reds for me need to be
applied thick. That means reds are limited to the inside of bowls and
the upper portion of other forms. I haven't risked my shelves by
glazing thick red all the way to the bottom of a pot. Learn the best
places in your kiln for reds and put the pots there.

Kathi

Craig Martell on thu 30 aug 07


Lesley was asking:
>I have a cone 10, copper red question here.
>not ever really rich reds - not like the stuff that comes out of my
>buddies brick kiln. Any reason for this?

Hello Lesley:

Copper reds like a slow cool from about 2000 down to 1950F or somewhere in
that neighborhood. Your fiber kiln doesn't store as much heat as a brick
kiln so you cool quicker. Try reignition of the burners at about 2000F and
drop the kiln to around 1950F and hold it there for an hour, maybe more
time or less, in neutral or oxidation. Reduction doesn't seem to be
necessary to bring up a redder red by doing the above. It seems that iron
and copper reds both like the slow cool to develop the crystals that make
the red.

I had some copper reds that I was working on and they were coming out a bit
transparent and "mules liver purple." It was the too rapid cooling that
messed up the works even though I have a k-26 hotface kiln. I refired the
reds to 1988F in the electric kiln and they came out nice and red. Next
firing (gas kiln) I had some copper reds with black oil spots and I
downfired in oxidation from 2000F to 1950F and held the temp for about a
half hour and the glazes were red and I was able to enjoy "Miller Time"
after unloading. No, I wasn't drinking beer I was listening to Steve Miller.

regards, Craig Martell Hopewell, Oregon

Marcia Selsor on thu 30 aug 07


I fired cone reds consistently at ^6 starting with reduction about
^09 to ^04 and then neutral to about ^5
soft reduction for about an hour while 6 drops. Clear in oxidation
for about 10 minutes.
For a while I would throw sticks into the burner ports or peepholes
every so often until the color starting going. (a few hours)
Don't know if it was voodoo or not. But I got nice reds.

Marcia Selsor
http://marciaselsor.com

Lee Love on fri 31 aug 07


Many of the old pots were fired in saggers. They help stabilize the
atmosphere around the pot in large wood kilns that have cycles of oxidation
blowing through the kiln.

You can also brush oxides on the inside of the sagger and they can
effect the glaze surface of the pot, depending upon how reactive the glaze
is to oxides.

Ken Matsuzaki uses the painted oxide method with his shinos, to make
them blush on the surface of the glaze and not just where it the glaze is
thin.
--
Lee in Minneapolis, Minnesota USA

"Making pots should not be a struggle.
It should be like walking down a hill
in a gentle breeze." --Shoji Hamada


http://mashikopots.blogspot.com/

"

smdilley@sdcoe.k12.ca.us on fri 31 aug 07


Pay special extra attention to your body reduction and final reduction=2E=20=

You can also strike the kiln after you have finished firing=2E Open dampe=
r
and allow the kiln to cool to a dull red=2E (OE THERE ABOUTS)Then turn
burners back on and close damper, start timing it after black carbon smoke=

appears=2E "Strike" it from 1-5 minutes shut off gas allow kiln to cool=2E=

open, enjoy reds!!
good luck
steve dilley=20

Original Message:
-----------------
From: Lesley Anton lesleyanton@MAC=2ECOM
Date: Thu, 30 Aug 2007 10:04:47 -0700
To: CLAYART@LSV=2ECERAMICS=2EORG
Subject: Copper Reds


Hi there,
I have a cone 10, copper red question here=2E I have a 9 cubic foot
fiber updraft kiln=2E I am wondering if any of you have developed any
tricks to getting a consistant red with this kind of kiln=2E

Mel Jacobson - I happened upon a posting from long ago that you had
said "at the end of the firing, pull the peeps, and turn off the
burners for about 10 minutes until the temp drops to 1900, then close
it back up, and hold there for an hour and a half=2E Then close it up
tight=2E"

I have had ok results with this, mainly probably due to thickness of
glaze, but when I go thicker, I get some runs at the bottom=2E But not
ever really rich reds - not like the stuff that comes out of my
buddies brick kiln=2E Any reason for this=3F

Any response would be welcomed=2E

Lesley Anton


Lesley Anton Handmade Ceramic Lighting
www=2Elesleyanton=2Ecom

=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=5F=
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John Fulwood on fri 31 aug 07


Mel,


Nothing about making and firing pots is written in stone.

I get beautiful copper reds, dark purple and light pink in the same kiln load. I reduce from 2000 degrees until cone 10 is flat. I often quick cool the kiln to 1300 and then close it up. If we could only be inside to see how and when all the magic happens. Kilns, clay bodies, glaze materials...... too many variables for one answer to each question but it sure is fun to try to figure it all out and make it happen again in the next firing.

Time to glaze some pots,

John Fulwood

John Fulwood
Kissimmee River Pottery
One 8th St. #11
Frenchtown, NJ. 08825
http://www.kissimmeeriverpottery.com

David Cuzick on fri 31 aug 07


Copper reds, yeah, boy, that can to be a difficult thing to achieve. I have been firing copper reds for many years now with very good results. I believe that the most important thing is when you start the reduction. That can be tricky because what you see through your peep hole may not be the same as what is occurring in the rest of the kiln or certain areas of the kiln. But early reduction is key, start around ^010 , but again you may need to go even lower if the shelf the cone is on is cooler than other parts of the kiln, or a cone up if that is a hot area. I think the later reduction does little to produce reds as the glaze is glassed over and not receptive to the reduction. The slow cooling will affect surface quality, but in my experience not the color of the red. I oxidize my kiln for 1/2hour to 45 minutes at the end of the firing, it improves the reds clarity... that was hard to believe the first time I did it, but there is no loss of color if you have it in the
first place. The oxidation period also is great for updraft kilns to let the top catch up to the bottom. My firings are cooled naturally for about 20 hours.
These are just my observations in my kilns.
David Cuzick in San Diego

Lesley Anton wrote: Thanks to everyone for some fine advise. I wlll give it a slower
cool next time. This most recent firing though, I cooled to 1900,
then let it sit there for 1 1/2 hours and then shut it down. The
result was light red, with nice red in the creases of the pot, and
almost white on the upper surface - I think the glaze was too thin
( I counted to 2 in the glaze bucket). I'm going to refire those,
dipping them once more when they're hot, but I have some more that I
still have to fire, that I put a thicker coat (counted to 3.5 in the
glaze bucket) on and will try to soak from 2000 to 1800 for 4 hrs,
this time. Then shut it down.

I get so paranoid about dripping that I under do the glaze coverage
sometimes.
I also sometimes get started too late, then end up having to pull
3am nights - argh.

Wish me luck.

Lesley Anton Handmade Ceramic Lighting
323.934.3463
www.lesleyanton.com

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Craig Martell on sun 2 sep 07


John was saying:
>all this talk of soaking and down firing with copper reds. In my mind,
>this is not
>the main consideration when trying to get copper reds.
>The main consideration is to have a good recipe, put the glaze on thick
>enough and reduce early enough.

Hello John:

I don't think that anyone was suggesting that the cooling of copper reds is
the "main" consideration. It has a lot of influence on whether or not one
achieves a rich red. The original question about reds dealt with the
cooling of the glaze in a fiber kiln so some of us proceeded from there and
addressed the cooling concern. The composition of a copper red and proper
application of the glazes are discussed more often than the cooling factor
and may be more "common knowledge" than other things that produce a
pleasing copper red glaze.

Holding temperature at certain phases of the fire are really not a
trick. If you want to use that term it's fine but I don't think there are
any tricks to be used. I think technique describes it better. My take on
making reds is that all of the above, glaze comp., application, firing are
all important things to consider and learn. The only thing that I don't
totally agree with is when to start reduction. Cone 012 is fine but one
can achieve good reds with reduction starting as late as 06. That's what
I've used for the last 20 years and it's worked well and the reds have
usually been very good except when I cool too quickly. But when to begin
reduction has a lot to do with glaze composition and clay used so it will
vary with potters. But to say that you have to reduce as early as 012 or
you will not get a copper red is just not the case from my experience.

regards, Craig Martell Hopewell, Oregon

John Britt on mon 3 sep 07


Craig,

I definitely don't mean you "have to begin reduction at 012", in fact, I
like to reduce closer to 08 - 05 as you say to make the glaze more
interesting. Sometimes starting at cone 012 makes it too flat.

Nice post,

John Britt
www.johnbrittpottery.com

jonathan edward byler on thu 3 apr 08


yes, very nice, but where is the glaze formula???? Edouard, all of
your other fine posts at least give a hint as where to start...

thanks,

jon

On Apr 3, 2008, at 8:37 PM, Veena Raghavan wrote:

> Edouard,
>
> Thanks for sharing. Loved the copper reds and some of his other
> glazes too.
> Also loved the shinos you posted recently. I have been using your
> ash floating
> blue, and love it.
>
> Thanks.
>
> Veena
>
>
> In a message dated 4/3/2008 9:21:11 PM Eastern Daylight Time,
> edouardb@SOREL-TRACY.QC.CA writes:
>>
>> Beautiful copper reds here,
>>
>>
>> http://www.flickr.com/photos/albertobagetto/
>>
>>
>> Gis revido,
>
> VeenaRaghavan@cs.com
>
> ______________________________________________________________________
> ________
> Clayart members may send postings to: clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post messages, change your
> subscription settings or unsubscribe/leave the list here: http://
> www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be reached at
> melpots2@visi.com

Edouard Bastarache Inc. on thu 3 apr 08


Beautiful copper reds here,


http://www.flickr.com/photos/albertobagetto/


Gis revido,
(A la revoyure)

Edouard Bastarache=20
Spertesperantisto

Sorel-Tracy
Quebec

http://www.pshcanada.com/Toxicology.htm
http://www.flickr.com/photos/30058682@N00/
http://www.flickr.com/photos/potier/20321056/
http://perso.orange.fr/smart2000/livres.htm
http://myblogsmesblogs.blogspot.com/

Veena Raghavan on thu 3 apr 08


Edouard,

Thanks for sharing. Loved the copper reds and some of his other glazes too.
Also loved the shinos you posted recently. I have been using your ash floating
blue, and love it.

Thanks.

Veena


In a message dated 4/3/2008 9:21:11 PM Eastern Daylight Time,
edouardb@SOREL-TRACY.QC.CA writes:
>
> Beautiful copper reds here,
>
>
> http://www.flickr.com/photos/albertobagetto/
>
>
> Gis revido,

VeenaRaghavan@cs.com

Edouard Bastarache Inc. on fri 4 apr 08


Jon,

these are not my pots but Albert Galletto's
in Italy, by the way he is also an agronomist.

Gis revido,
(A la revoyure)

Edouard Bastarache
Spertesperantisto

Sorel-Tracy
Quebec

http://www.pshcanada.com/Toxicology.htm
http://www.flickr.com/photos/30058682@N00/
http://www.flickr.com/photos/potier/20321056/
http://perso.orange.fr/smart2000/livres.htm
http://myblogsmesblogs.blogspot.com/




----- Original Message -----
From: "jonathan edward byler"
To:
Sent: Thursday, April 03, 2008 10:35 PM
Subject: Re: Copper reds


> yes, very nice, but where is the glaze
> formula???? Edouard, all of
> your other fine posts at least give a hint as
> where to start...
>
> thanks,
>
> jon
>
> On Apr 3, 2008, at 8:37 PM, Veena Raghavan
> wrote:
>
>> Edouard,
>>
>> Thanks for sharing. Loved the copper reds and
>> some of his other
>> glazes too.
>> Also loved the shinos you posted recently. I
>> have been using your
>> ash floating
>> blue, and love it.
>>
>> Thanks.
>>
>> Veena
>>
>>
>> In a message dated 4/3/2008 9:21:11 PM Eastern
>> Daylight Time,
>> edouardb@SOREL-TRACY.QC.CA writes:
>>>
>>> Beautiful copper reds here,
>>>
>>>
>>> http://www.flickr.com/photos/albertobagetto/
>>>
>>>
>>> Gis revido,
>>
>> VeenaRaghavan@cs.com
>>
>> ______________________________________________________________________
>> ________
>> Clayart members may send postings to:
>> clayart@lsv.ceramics.org
>>
>> You may look at the archives for the list, post
>> messages, change your
>> subscription settings or unsubscribe/leave the
>> list here: http://
>> www.acers.org/cic/clayart/
>>
>> Moderator of the list is Mel Jacobson who may
>> be reached at
>> melpots2@visi.com
>
> ______________________________________________________________________________
> Clayart members may send postings to:
> clayart@lsv.ceramics.org
>
> You may look at the archives for the list, post
> messages, change your
> subscription settings or unsubscribe/leave the
> list here: http://www.acers.org/cic/clayart/
>
> Moderator of the list is Mel Jacobson who may be
> reached at melpots2@visi.com
>

dianamp@COMCAST.NET on mon 31 jan 11


Hi Clayart:


I remember doing tests on copper red formulae at Pewabic
about 30 years ago. I changed the feldspar in each test,
using the same formula. They varied from red to purple.


I can't remember which feldspar gave purple and which red,
but the base formulae is VERY important to the color it gives.
So don't begin with just any copper formula; use one which
was designed for RED.


Diana Pancioli