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copper carb and slip resist

updated thu 11 feb 99

 

Birdie Boone on sat 6 feb 99

Hello,

I'm wondering if anyone out there knows what happens if a copper carb
wash (copper carb and water) is painted onto a leather hard piece,
burnished, bisqued and then pit fired. Will this work to get color
flashes in a pit or does the burnishing and/or bisquing ruin copper
carbs abilities?

I am also looking for a recipe for slip resist and wondering if it could
be used in pit firings as it is used in raku firings?

Thanks much,
Birdie,
Abingdon, VA

Marty Anderson on sun 7 feb 99

Birdie,

We do not put copper carb on our pots, but we do terra sig them and then
bisque. The copper carb is sprinkled heavily around each pot on the sawdust
with Kosher salt. I have read where the copper was put directly on the pot
when pit fired.

Any help out there on copper being put on as a powder, or as a wash when pit
fired?

marty
martya@airmail.net

-----Original Message-----
From: Birdie Boone
To: CLAYART@LSV.UKY.EDU
Date: Saturday, February 06, 1999 5:57 PM
Subject: Copper Carb and Slip Resist


>----------------------------Original message----------------------------
>Hello,
>
>I'm wondering if anyone out there knows what happens if a copper carb
>wash (copper carb and water) is painted onto a leather hard piece,
>burnished, bisqued and then pit fired. Will this work to get color
>flashes in a pit or does the burnishing and/or bisquing ruin copper
>carbs abilities?
>
>I am also looking for a recipe for slip resist and wondering if it could
>be used in pit firings as it is used in raku firings?
>
>Thanks much,
>Birdie,
>Abingdon, VA
>

the cat lady on mon 8 feb 99

Marty Anderson wrote:

> ----------------------------Original message----------------------------
> Birdie,
>
> We do not put copper carb on our pots, but we do terra sig them and then
> bisque. The copper carb is sprinkled heavily around each pot on the sawdust
> with Kosher salt. I have read where the copper was put directly on the pot
> when pit fired.
>
> Any help out there on copper being put on as a powder, or as a wash when pit
> fired?
>

I do not terra sig my pots, just burnish with a rubber rib after trimming. I
use Tucker's ^10 smoothstone and bisque to 06. I rub copper carb powder into
the pot with my hands, place the pot onto layered colourful shiny paper with
rock salt between all the layers and roll up the package tightly before putting
into my pit fire. I fire hot - so hot that I can't approach the pit due to heat
- then cover and ignore for at least 24 hours. I get some wonderful, non-fading
copper reds with swirls of black, mauve, grey etc.

--
sam - alias the cat lady
Melbourne, Ontario
SW Ontario CANADA
http://www.geocities.com/paris/3110
scuttell@odyssey.on.ca

"Thousands of years ago, cats were worshipped as gods.
Cats have never forgotten this."

Lynne Berman on mon 8 feb 99

Here are a bunch of resist slip recipes. Have tried them in the saggar and
they work. Should work in a pit fire.
Lynne Berman

NAKED RAKU
Resist Slips and Glazes To Go With Them

David Roberts resist slip
(EPK)Kaolin 3 parts by volume
Flint 2 parts by volume
Copper Oxide 10% (or none)

use with the following glaze
Raku Crackle Glaze
(by David Roberts in Sawdust Firing)
High Alkali Frit 45%
Soft Borax Frit 45%
China Clay 10%

Fire to 1562-1652F.

Glaze Marie-Claire in the Netherlands
90% Borax frit
10% kaolin
____________________________________________________
Resist Slip Marie-Claire
2 parts kaolin
3 parts flint or silica

works with

Glaze
Frit 3110 65%
Gerstley Borate 35%

don't use this glaze with the Roberts slip
__________________________________________________
Jacobsons' Slip and Glaze
Slip
40% Lincoln 60 fireclay
30% 6-Tile clay
20% Ione 412 Grog
10% Custer feldspar

or this variation used without glaze

Chip n Slip
40% Hawthrone Bone or A-P Fireclay
30% Kaolin
20% Pyrotol (or grog)
10% Custer Feldspar


Glaze
60% Ferro Frit 3110
40% Gerstley Borate

Bisque to Cone 012-010
Fire to cone 014 (1540F.), smoke, water-quench, peel
___________________________________________________________
Gordon Hutchens Slip
used without glaze

Fire Clay 50
EPK 30
Alumina Hydrate 20 (or 10% for easier removal)




Marci Masterson
(From Sharon in Fort Worth)
#1
Fire Clay 40 grams
#6 Tile 30 grams
Custer 10 grams
Grog (28 mesh) 20 grams

#3
Fire Clay 50 grams
EPK 40 grams
Soda Spar 10 grams
(Add 5 - 15% grog)

#4
Fire Clay 50 grams
EPK 35 grams
Nepheline Syenite 15 grams
(add 5% grog - no more)

#5
Fire Clay 45 grams
EPK 35 grams
Flint 10 grams
Nepheline Syenite 10 grams
(add 5% Grog - no more)

Notes:
(can't find #2)
#1. If fire clay is gritty, don't need grog (or need less grog). Interesting
small
design w/o grog. Marcie uses 10% grog. Apply one thinned coat crubbed.
Removes very
easily.

#3. Similar to #1. Marcie uses 10% grog.

#4. Semi straight edge design. Applies 4 even coats. Thinner and smaller
design.
Removed easily.

#5. Fairly straight edge design (almost geometric). Hard to remove. Apply
like #4.
Used w/o grog is good but small.

Additional notes: Every thing with talc "fused". Try other fluxes; try other
clays.
Almost all recipes will work with 25-50% raku claybody w/grog or sand. Mix
slip to a
consistency where it will just "pour" not "plop" off a spoon.

The following is the glaze recipe which is applied over the slip:

70% Ferro Frit 3110
30% Gerstly Borate

Mix "milk" thin and apply thinly.

Chris Leake on mon 8 feb 99

Birdie,

My husband and I have gotten some great colors using a recipe from an
old CM article about Federighi where the colorants are mixed in the
terra sig. It is as follows:

1400 grams water
600 grams ball clay
40 grams Calgon

then I added:

10 grams copper carbonate to one batch
20 grams red iron oxide to another, and
50 grams of rutile to a third.

We have gotten some great results especially when we wrap the pots in
seaweed.

Chris

gburning.mail on wed 10 feb 99

What exactly does a resist slip do in the raku?

Lynne Berman wrote:

> ----------------------------Original message----------------------------
> Here are a bunch of resist slip recipes. Have tried them in the saggar and
> they work. Should work in a pit fire.
> Lynne Berman
>
> NAKED RAKU
> Resist Slips and Glazes To Go With Them
>
> David Roberts resist slip
> (EPK)Kaolin 3 parts by volume
> Flint 2 parts by volume
> Copper Oxide 10% (or none)
>
> use with the following glaze
> Raku Crackle Glaze
> (by David Roberts in Sawdust Firing)
> High Alkali Frit 45%
> Soft Borax Frit 45%
> China Clay 10%
>
> Fire to 1562-1652F.
>
> Glaze Marie-Claire in the Netherlands
> 90% Borax frit
> 10% kaolin
> ____________________________________________________
> Resist Slip Marie-Claire
> 2 parts kaolin
> 3 parts flint or silica
>
> works with
>
> Glaze
> Frit 3110 65%
> Gerstley Borate 35%
>
> don't use this glaze with the Roberts slip
> __________________________________________________
> Jacobsons' Slip and Glaze
> Slip
> 40% Lincoln 60 fireclay
> 30% 6-Tile clay
> 20% Ione 412 Grog
> 10% Custer feldspar
>
> or this variation used without glaze
>
> Chip n Slip
> 40% Hawthrone Bone or A-P Fireclay
> 30% Kaolin
> 20% Pyrotol (or grog)
> 10% Custer Feldspar
>
> Glaze
> 60% Ferro Frit 3110
> 40% Gerstley Borate
>
> Bisque to Cone 012-010
> Fire to cone 014 (1540F.), smoke, water-quench, peel
> ___________________________________________________________
> Gordon Hutchens Slip
> used without glaze
>
> Fire Clay 50
> EPK 30
> Alumina Hydrate 20 (or 10% for easier removal)
>
> Marci Masterson
> (From Sharon in Fort Worth)
> #1
> Fire Clay 40 grams
> #6 Tile 30 grams
> Custer 10 grams
> Grog (28 mesh) 20 grams
>
> #3
> Fire Clay 50 grams
> EPK 40 grams
> Soda Spar 10 grams
> (Add 5 - 15% grog)
>
> #4
> Fire Clay 50 grams
> EPK 35 grams
> Nepheline Syenite 15 grams
> (add 5% grog - no more)
>
> #5
> Fire Clay 45 grams
> EPK 35 grams
> Flint 10 grams
> Nepheline Syenite 10 grams
> (add 5% Grog - no more)
>
> Notes:
> (can't find #2)
> #1. If fire clay is gritty, don't need grog (or need less grog). Interesting
> small
> design w/o grog. Marcie uses 10% grog. Apply one thinned coat crubbed.
> Removes very
> easily.
>
> #3. Similar to #1. Marcie uses 10% grog.
>
> #4. Semi straight edge design. Applies 4 even coats. Thinner and smaller
> design.
> Removed easily.
>
> #5. Fairly straight edge design (almost geometric). Hard to remove. Apply
> like #4.
> Used w/o grog is good but small.
>
> Additional notes: Every thing with talc "fused". Try other fluxes; try other
> clays.
> Almost all recipes will work with 25-50% raku claybody w/grog or sand. Mix
> slip to a
> consistency where it will just "pour" not "plop" off a spoon.
>
> The following is the glaze recipe which is applied over the slip:
>
> 70% Ferro Frit 3110
> 30% Gerstly Borate
>
> Mix "milk" thin and apply thinly.