sspottery@OGLECOM.COM on fri 9 aug 02
Why is it that some of my pots with copper red glaze turn pink? I've =
been using a glaze similar to Tom Coleman's for over 20 years now and =
fire to cone 9. The pots in the lower part of the kiln come out red, if =
the load is tight, and the shelf is really close to the pots below. Is =
it the temp, atmosphere, or circulation? I tried the re/fire idea this =
time and they still came this way. I use a HF 16 Alpine that still have =
the burners in the kiln (ref, Vince) and has worked fine for 24 years, =
except for this copper PINK problem. Any ideas? One good thing is that I =
do have customers that love the pink color. The problem is when they =
want a special order of it and it comes out RED. Oh well, that's the way =
with reduction I guess! Reed Bakken Slip & Slurry Pottery, Oregon, =
Il.
Mndy Rhoads on fri 9 aug 02
We have been having that same problem lately, they're turning a purple/pink.
We have been using Pete's cranberry (firing cone 10) for years and never
had any problem.. Some have suggested over reduction but we really haven't
changed much in the way we fire...some say it may be the addition of a new
glaze that's leaching out and it may take a few firings to clean out the
kiln but we have fired now 5 firings and it's still there..some say bad
gersley borate, different copper..It's very frustrating.. I know of another
potter that is having the same problem..
Mindy
Peaceful Priaire Pottery
From:
To:
Sent: Friday, August 09, 2002 1:17 PM
Subject: Copper Reds to Pink
Why is it that some of my pots with copper red glaze turn pink? I've been
using a glaze similar to Tom Coleman's for over 20 years now and fire to
cone 9. The pots in the lower part of the kiln come out red, if the load is
tight, and the shelf is really close to the pots below. Is it the temp,
atmosphere, or circulation? I tried the re/fire idea this time and they
still came this way. I use a HF 16 Alpine that still have the burners in
the kiln (ref, Vince) and has worked fine for 24 years, except for this
copper PINK problem. Any ideas? One good thing is that I do have customers
that love the pink color. The problem is when they want a special order of
it and it comes out RED. Oh well, that's the way with reduction I guess!
Reed Bakken Slip & Slurry Pottery, Oregon, Il.
____________________________________________________________________________
__
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Michelle Lowe on fri 9 aug 02
At 12:18 PM 8/9/2002 -0500, you wrote:
>We have been having that same problem lately, they're turning a purple/pink.
>We have been using Pete's cranberry (firing cone 10) for years and never
>had any problem..
Hm, and here I thought it was just me. I am thinking I will try a different copper red recipe and see what it does. I have been using Pete's Cranberry, and getting pink/purples inconsistently also.
-----------
Michelle Lowe potter in the Phoenix desert
http://www.desertdragonpottery.com
Mishy@desertdragonpottery.com
mishlowe@amug.org
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Paul Taylor on fri 9 aug 02
Dear slurry
If you market your stuff in a rural area note that here slurry is the
polite term for animal excrement.
What is probably happening is that a particle size of one of your materials
is changing while the glaze it is in the bucket. This always hapens with
reds I suspect the tin or maybe the copper or it could be ------- ????
A higher firing would compensate which explains why you may think it is the
kiln at fault.
Also copper glazes need 0.3 millimeters thickness minimum that could make
a difference.
And rate of the cooling may change in the winter.
My money would be on the first suggestion.
copper reds God help us
--
Regards from Paul Taylor
http://www.anu.ie/westportpottery
The boy who announced that the king had no clothes was tortured for the
names of his confederates and then shot.
> From: sspottery@OGLECOM.COM
> Reply-To: Ceramic Arts Discussion List
> Date: Fri, 9 Aug 2002 11:17:09 -0700
> To: CLAYART@LSV.CERAMICS.ORG
> Subject: Copper Reds to Pink
>
> Why is it that some of my pots with copper red glaze turn pink? I've been
> using a glaze similar to Tom Coleman's for over 20 years now and fire to cone
> 9. The pots in the lower part of the kiln come out red, if the load is tight,
> and the shelf is really close to the pots below. Is it the temp, atmosphere,
> or circulation? I tried the re/fire idea this time and they still came this
> way. I use a HF 16 Alpine that still have the burners in the kiln (ref,
> Vince) and has worked fine for 24 years, except for this copper PINK problem.
> Any ideas? One good thing is that I do have customers that love the pink
> color. The problem is when they want a special order of it and it comes out
> RED. Oh well, that's the way with reduction I guess! Reed Bakken Slip &
> Slurry Pottery, Oregon, Il.
>
Rikki Gill on fri 9 aug 02
Do you reglaze the red before refiring? It works for me. Good luck,
Rikki
----- Original Message -----
From:
To:
Sent: Friday, August 09, 2002 11:17 AM
Subject: Copper Reds to Pink
Why is it that some of my pots with copper red glaze turn pink? I've been
using a glaze similar to Tom Coleman's for over 20 years now and fire to
cone 9. The pots in the lower part of the kiln come out red, if the load is
tight, and the shelf is really close to the pots below. Is it the temp,
atmosphere, or circulation? I tried the re/fire idea this time and they
still came this way. I use a HF 16 Alpine that still have the burners in
the kiln (ref, Vince) and has worked fine for 24 years, except for this
copper PINK problem. Any ideas? One good thing is that I do have customers
that love the pink color. The problem is when they want a special order of
it and it comes out RED. Oh well, that's the way with reduction I guess!
Reed Bakken Slip & Slurry Pottery, Oregon, Il.
____________________________________________________________________________
__
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.
Mndy Rhoads on fri 9 aug 02
I don't know about Reed but we have fired great reds for 15 years and have
never had this problem until about 6 weeks ago...mindy
----- Original Message -----
From: "Paul Taylor"
To:
Sent: Friday, August 09, 2002 4:20 PM
Subject: Re: Copper Reds to Pink
> Dear slurry
>
> If you market your stuff in a rural area note that here slurry is the
> polite term for animal excrement.
>
> What is probably happening is that a particle size of one of your
materials
> is changing while the glaze it is in the bucket. This always hapens with
> reds I suspect the tin or maybe the copper or it could be ------- ????
>
> A higher firing would compensate which explains why you may think it is
the
> kiln at fault.
>
> Also copper glazes need 0.3 millimeters thickness minimum that could
make
> a difference.
>
> And rate of the cooling may change in the winter.
>
> My money would be on the first suggestion.
>
> copper reds God help us
>
>
>
> --
> Regards from Paul Taylor
>
> http://www.anu.ie/westportpottery
>
> The boy who announced that the king had no clothes was tortured for the
> names of his confederates and then shot.
>
> > From: sspottery@OGLECOM.COM
> > Reply-To: Ceramic Arts Discussion List
> > Date: Fri, 9 Aug 2002 11:17:09 -0700
> > To: CLAYART@LSV.CERAMICS.ORG
> > Subject: Copper Reds to Pink
> >
> > Why is it that some of my pots with copper red glaze turn pink? I've
been
> > using a glaze similar to Tom Coleman's for over 20 years now and fire to
cone
> > 9. The pots in the lower part of the kiln come out red, if the load is
tight,
> > and the shelf is really close to the pots below. Is it the temp,
atmosphere,
> > or circulation? I tried the re/fire idea this time and they still came
this
> > way. I use a HF 16 Alpine that still have the burners in the kiln (ref,
> > Vince) and has worked fine for 24 years, except for this copper PINK
problem.
> > Any ideas? One good thing is that I do have customers that love the pink
> > color. The problem is when they want a special order of it and it comes
out
> > RED. Oh well, that's the way with reduction I guess! Reed Bakken
Slip &
> > Slurry Pottery, Oregon, Il.
> >
>
>
____________________________________________________________________________
__
> 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.
>
>
sspottery@OGLECOM.COM on sat 10 aug 02
I'm glad I'm not alone in this problem,misery loves company. I do tend =
to believe the pink problem comes from the atmosphere in the kiln. The =
pink glaze is crazed while the red isn't. I had a large bowl on the =
bottom shelf that came out red. The next shelf produced red to pink, the =
pots on the rest of the shelves came out pink. Same glaze, 2 coats =
thick. I reduce at c/010 for about 4/5 hours, oxidize up to cone 8 and =
reduce from there to cone 9/10. The re/fire was after the kiln cooled =
for 2 1/2 hours, I started it up again and fired on low burners for an =
hour, raising the temp 100 degrees F, then closed it up to cool. That =
re/fire idea came from Mayor Mel. I have herd that the amount of =
hydrogen in the atmosphere plays a role but don't know haw to tell other =
than one of those expensive analyzers, can't afford that, just a poor =
but happy potter! I have noticed better reds on a overcast day with =
lots of humidity. I have reglazed and refired many times with fine =
results. I just thought this idea of Mels would be the final thing I =
needed for a perfect copper red load. I guess there is no perfect one, =
just need more Kiln Gods next time. Thank again, Back to work, Reed
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