Talbott on mon 18 aug 97
I am having problems with volitization of copper on some of my pots... I
am considering placing a ceramic dish filled with copper carb in the center
of the kiln during a cone 9/10 glaze fire... Has anyone ever heard of
doing this? Your comments would be appreciated...
Also how about comments on firing schedules in regards to oxidation and
reduction.... I have heard of one potter who reduces for a while and then
oxidizes for a while and continues this flip flop till cone 10..
What is the word on the cone 06 copper raincoat... ...Marshall
1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
http://fmc.utm.edu/~dmcbeth/cag/naples.htm
2nd Annual Clayarters' Gallery details will be forth coming!!!
Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
WBS Live Chat Room, Sat Nites 10 PM EDT & Sun Afternoons at
1 PM EDT Private Room: Clayarters E-MAIL: clupus@ime.net
June Perry on wed 20 aug 97
Dear Marshall:
I have found that alternating oxidation and reduction gave me much brighter
colors. I could see quite a noticeable difference doing a 45 minute
alternating between strong reduction (no black smoke necessary) and
oxidation. I usually started a light body reduction quite early (around 1450
Degrees F) because of wanting those deep red shinos, then went into oxidation
for 45 minutes to an hour and then back and forth between oxidation and
reduction every 45 minutes to an hour. I don't go into the heavier reduction
until I'm past around 1600degrees F. I used to go heavier early but found it
wasn't necessary and the body seemed to fare better without such heavy
reduction and I still got nice warm body color with the black coring I would
sometimes get with too heavy early reduction. I ease up the reduction at the
very end and I don't usually soak at top temperature perse, just take about
an hour between the last two cones. I get great shinos and celadons using
this schedule. My little 12 cu.ft geil kiln is turned on the night before
with just the heat from the pilot system and then turned on early am. My
firing from that point is usually around fifteen hours. I could take it up
quite a bit faster but when I have I haven't liked the outcome as well. I'm
not sure how this schedule would work with copper reds. My late friend Vivika
Heino used to fire her copper reds with reduction from about 1800 all the way
to the end, with an early body reduction, then oxidizing until around 1800. I
have a bunch of copper red tests ready to go this fall when my garden is put
to rest and I'm eager to try that strike firing technique that one of our
members put on the list yesterday.
Regards,
June
Kathleen Schnaidt on wed 20 aug 97
When I used to fire a lot of copper reds, I:
* blocked the pieces in as much as possible so the draft wouldn't
carry away the copper -- in the center of shelves, ideally with
protector pots around them or soft brick ifnothing else, and the
covering shelf absolutely as tight as possible
* began reduction no later than cone 08, ideally at cone 010 (this
can be bad for dark stoneware, though, as it can cause carbon coring)
* Lightened reduction around cone 1 then increased it later, if it
hadn't built up
* oxidized for some minutes once I had reached temperature --
brightened the colors.
*someone I know used to put a little iron oxide in their copper reds
-- claiming that it helped to hold them!?
KS schnaidt@warren.med.harvard.edu
______________________________ Reply Separator _________________________________
Subject: Copper Carb Pool... volitizing copper...
Author: Ceramic Arts Discussion List at HMS-Internet
Date: 8/18/97 11:53 PM
----------------------------Original message----------------------------
I am having problems with volitization of copper on some of my pots... I
am considering placing a ceramic dish filled with copper carb in the center
of the kiln during a cone 9/10 glaze fire... Has anyone ever heard of
doing this? Your comments would be appreciated...
Also how about comments on firing schedules in regards to oxidation and
reduction.... I have heard of one potter who reduces for a while and then
oxidizes for a while and continues this flip flop till cone 10..
What is the word on the cone 06 copper raincoat... ...Marshall
1ST ANNUAL CLAYARTERS' GALLERY - NAPLES, MAINE (Summer 1997)
http://fmc.utm.edu/~dmcbeth/cag/naples.htm
2nd Annual Clayarters' Gallery details will be forth coming!!!
Celia & Marshall Talbott, Pottery By Celia, Route 114, P O Box 4116,
Naples, Maine 04055-4116,(207)693-6100 voice and fax,(call first)
WBS Live Chat Room, Sat Nites 10 PM EDT & Sun Afternoons at
1 PM EDT Private Room: Clayarters E-MAIL: clupus@ime.net
David Hendley on wed 20 aug 97
>Also how about comments on firing schedules in regards to oxidation and
>reduction.... I have heard of one potter who reduces for a while and then
>oxidizes for a while and continues this flip flop till cone 10..
By far, the best copper reds I have ever achieved are from my wood fired
kiln. I think this is because the atmosphere is going from reduction, to
neutral, to oxidation every few minutes all day. I emphasize the word
"think", because the more I try to figure out how copper reds work, the
less sure I am about anything!
I also don't think (there's that word again) your dish of copper card. will
do you much good, mostly because such a small surface area would be exposed.
David Hendley
Maydelle, Texas
Jaine & George on wed 20 aug 97
Marshall, I've not used a dish, but have had great success loading
small, L-shaped, bisqued pieces ['test tile' size] with Cu carb and
placing them around and about the kiln. This would seem to have the
advantage of permeating more of the kiln atmosphere with the Cu.
Jaine
Talbott wrote:
>
> ----------------------------Original message----------------------------
> I am having problems with volitization of copper on some of my pots... I
> am considering placing a ceramic dish filled with copper carb in the center
> of the kiln during a cone 9/10 glaze fire... Has anyone ever heard of
> doing this? Your comments would be appreciated...
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