Elizabeth Herod on sat 29 mar 03
I used the following terra sig recipe, and do not seem to be getting the
separation into 3 parts. There is a noticeable separation building up on
the bottom, but I do not seem to have the water on the top yet.
EPK 1170 grams
Ball Clay 270 grams
Bentonite 60 grams
Soda Ash 8 grams
Water 14 cups
Perhaps I am being too impatient. I moved the bucket last night, so if I
start counting from the time I moved it, I=B9d have another 14 hours to go fo=
r
it to separate, I guess.
Thanks
Beth
Eric Suchman on thu 3 jun 04
Could some one please send me the recipe for how much soda ash/sodium
silicate is added to how much clay and water for terra siggilata? My
recipes all use Calgon and that is different nowadays and Rhodes uses
Caustic soda which I don't have.
Thanks,
Eric in Oceanside
Vince Pitelka on thu 3 jun 04
> Could some one please send me the recipe for how much soda ash/sodium
> silicate is added to how much clay and water for terra siggilata?
Eric -
You can find an article I wrote on terra sig at
http://www.digitalfire.ab.ca/cermat/education/274.html
The article includes full instructions for making a superior terra sig. It
is a fairly complex process, but well worth it if you want the best sig.
Good luck -
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Vince Pitelka on fri 4 jun 04
> 1. Everybody seems to be selling sodium silicate in ready mixed liquid
form
> which tends to make it hard to measure dry weights. Know of any place it
is
> still sold in dry form
Doric -
I do not know of anyone who has ever sold sodium silicate in dry form. You
just weigh it in liquid form, just as if it was a dry material. I do not
understand why people have such a hard time with this.
> 2. Ball clay seems like such a nice generic term but everybody seems to
have
> their very own varieties of about 8-10 different ball clays. Any
> recommendation for which have the finest particles [or words to the wise
> about nasty ones to stay away from] or will any ball clay do?
I have made good white terra sig with the old stand-by - OM-4 Kentucky ball
clay. But keep in mind that when you use a very fine clay like ball clay
you usually do not get the clearly defined layers in the settling buckets.
So just siphon off 2/3 of the liquid and discard the rest.
Whenever you are settling and siphoning terra sig, do not ever discard the
top clear layer, if there is one. Even if it looks clear, there are
ultra-fine clay particles in that layer and you do not want to lose them.
It is worth it to include that clear layer when you siphon, and then go to
the extra trouble to concentrate back to a workable specific gravity.
> 3. Other than the "wine siphon sucks more air test", is there a visual
> distinction between the good stuff you want to siphon and the other stuff
> you don't want? Or will this be obvious when I actuall get around to doing
> it?
First, they don't call them "wine siphons" any more. If you search for them
online, the device is called a "racking cane."
My favorite terra sig is made from Redart clay, and it develops a very
clearly defined layer of harder sediment, and you will have no trouble
identifying it. But otherwise, do not siphon down more than 2/3 of the way
down the bucket. It just isn't worth it. Clay is cheap, but by the time
you go to the trouble to make terra sig, you have a very special product.
Good luck -
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Doric T. Jemison-Ball II on fri 4 jun 04
Vince:
I'm about to try out your terra sig recipe, but I have a couple of
questions:
1. Everybody seems to be selling sodium silicate in ready mixed liquid form
which tends to make it hard to measure dry weights. Know of any place it is
still sold in dry form [Otherwise, I'm going to have to calculate the
difference in weight between a pint of water and the pint of ready mixed
sodium silicate and get fancy with the math [or just dry the stuff out]
2. Ball clay seems like such a nice generic term but everybody seems to have
their very own varieties of about 8-10 different ball clays. Any
recommendation for which have the finest particles [or words to the wise
about nasty ones to stay away from] or will any ball clay do?
3. Other than the "wine siphon sucks more air test", is there a visual
distinction between the good stuff you want to siphon and the other stuff
you don't want? Or will this be obvious when I actuall get around to doing
it?
Doric T.Jemison-Ball II
BBS-LA
14622 Ventura Blvd. #727
Sherman Oaks, CA 91403
Northern California
707-884-5067 Voice
707-884-5417 FAX
Southern California
818-262-6572 Message and Voice
buffalo@bbs-la.com
http://www.bbs-la.com
"He that would make his own liberty secure must guard even his enemy from
oppression; for if he violates this duty he establishes a precedent that
will reach to himself." --Thomas Paine
----- Original Message -----
From: "Vince Pitelka"
To:
Sent: Thursday, June 03, 2004 8:30 PM
Subject: Re: terra sig recipe
> > Could some one please send me the recipe for how much soda ash/sodium
> > silicate is added to how much clay and water for terra siggilata?
>
> Eric -
> You can find an article I wrote on terra sig at
> http://www.digitalfire.ab.ca/cermat/education/274.html
>
> The article includes full instructions for making a superior terra sig.
It
> is a fairly complex process, but well worth it if you want the best sig.
> Good luck -
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft, Tennessee Technological University
> Smithville TN 37166, 615/597-6801 x111
> vpitelka@dtccom.net, wpitelka@tntech.edu
> http://iweb.tntech.edu/wpitelka/
> http://www.tntech.edu/craftcenter/
>
>
____________________________________________________________________________
__
> 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.
>
Suzanne Wolfe on sun 6 jun 04
Vince,
I have one question re: your terrasig recipe. Given that you have made
a five gallon bucket with @ 16# redart, about how much off the top does
one siphon? The top quarter, the top eighth??? I know about the air-
sucking changes, but that is a little hard for me. Having an idea
about how much of the mix actually comes off will help me with my other
observations. Thanks.
Oh, one more question. Have you also tried red horse clay as well as
red art? Do you find them different?
Thanks and aloha,
Suzanne
----- Original Message -----
From: Vince Pitelka
Date: Thursday, June 3, 2004 5:30 pm
Subject: Re: terra sig recipe
> > Could some one please send me the recipe for how much soda
> ash/sodium> silicate is added to how much clay and water for terra
> siggilata?
> Eric -
> You can find an article I wrote on terra sig at
> http://www.digitalfire.ab.ca/cermat/education/274.html
>
> The article includes full instructions for making a superior terra
> sig. It
> is a fairly complex process, but well worth it if you want the
> best sig.
> Good luck -
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft, Tennessee Technological University
> Smithville TN 37166, 615/597-6801 x111
> vpitelka@dtccom.net, wpitelka@tntech.edu
> http://iweb.tntech.edu/wpitelka/
> http://www.tntech.edu/craftcenter/
>
>
________________________________________________________________________
______
> 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.
Doric T. Jemison-Ball II on mon 7 jun 04
Vince;
Thanks for all your help. I'll let you know how it turns out.
The wet vs dry sodium silicate problem "everybody" seems to have may be
because they assume .25% by weight dry is different than .25% by weight wet
[which it probably is] but that the instructions assume .25% by weight wet
because that's the only way you can get it.
I'll probably try both ball clay and redart.
Thanks again.
Doric T.Jemison-Ball II
BBS-LA
14622 Ventura Blvd. #727
Sherman Oaks, CA 91403
Northern California
707-884-5067 Voice
707-884-5417 FAX
Southern California
818-262-6572 Message and Voice
buffalo@bbs-la.com
http://www.bbs-la.com
"He that would make his own liberty secure must guard even his enemy from
oppression; for if he violates this duty he establishes a precedent that
will reach to himself." --Thomas Paine
----- Original Message -----
From: "Vince Pitelka"
To:
Sent: Friday, June 04, 2004 7:58 PM
Subject: Re: terra sig recipe
> > 1. Everybody seems to be selling sodium silicate in ready mixed liquid
> form
> > which tends to make it hard to measure dry weights. Know of any place it
> is
> > still sold in dry form
>
> Doric -
> I do not know of anyone who has ever sold sodium silicate in dry form.
You
> just weigh it in liquid form, just as if it was a dry material. I do not
> understand why people have such a hard time with this.
>
> > 2. Ball clay seems like such a nice generic term but everybody seems to
> have
> > their very own varieties of about 8-10 different ball clays. Any
> > recommendation for which have the finest particles [or words to the wise
> > about nasty ones to stay away from] or will any ball clay do?
>
> I have made good white terra sig with the old stand-by - OM-4 Kentucky
ball
> clay. But keep in mind that when you use a very fine clay like ball clay
> you usually do not get the clearly defined layers in the settling buckets.
> So just siphon off 2/3 of the liquid and discard the rest.
>
> Whenever you are settling and siphoning terra sig, do not ever discard the
> top clear layer, if there is one. Even if it looks clear, there are
> ultra-fine clay particles in that layer and you do not want to lose them.
> It is worth it to include that clear layer when you siphon, and then go to
> the extra trouble to concentrate back to a workable specific gravity.
>
> > 3. Other than the "wine siphon sucks more air test", is there a visual
> > distinction between the good stuff you want to siphon and the other
stuff
> > you don't want? Or will this be obvious when I actuall get around to
doing
> > it?
>
> First, they don't call them "wine siphons" any more. If you search for
them
> online, the device is called a "racking cane."
>
> My favorite terra sig is made from Redart clay, and it develops a very
> clearly defined layer of harder sediment, and you will have no trouble
> identifying it. But otherwise, do not siphon down more than 2/3 of the
way
> down the bucket. It just isn't worth it. Clay is cheap, but by the time
> you go to the trouble to make terra sig, you have a very special product.
> Good luck -
> - Vince
>
> Vince Pitelka
> Appalachian Center for Craft, Tennessee Technological University
> Smithville TN 37166, 615/597-6801 x111
> vpitelka@dtccom.net, wpitelka@tntech.edu
> http://iweb.tntech.edu/wpitelka/
> http://www.tntech.edu/craftcenter/
>
>
____________________________________________________________________________
__
> 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.
>
Vince Pitelka on wed 9 jun 04
> I have one question re: your terrasig recipe. Given that you have made
> a five gallon bucket with @ 16# redart, about how much off the top does
> one siphon? The top quarter, the top eighth???
Suzanne in beautiful Hawaii -
With Redart, the yield is quite high. I usually siphon off about 2/3 to 3/4
by volume, but of course that is a very thin liquid, because all the heavy
material has settled out, and must be concentrated a great deal to give a
1.15 s.g. suspension.
With Redart you will have no trouble at all identifying the layer of heavy
sediment. When your racking cane touches the division point, it will feel
like soft rubber. That is where a proper racking cane with the little cap
on the tip really helps out. The cane is specifically designed to allow
siphoning while picking up a minimum of sediments in the wine, and that is
exactly what you want it to do in the sig.
> Oh, one more question. Have you also tried red horse clay as well as
> red art?
I have not seen Red Horse clay advertised by any of our clay suppliers in
the Mid South, and have not used it. It may be a West Coast clay.
Best wishes -
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
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