easley59 on wed 31 dec 03
Someone once explained floc vs de floc as: flocculating is like =
gathering the flock, making the glaze thicker, molecules closer =
together. De flocculating =3D making it looser, more watery, the flock =
further apart, so to speak.
Simplistic, but easy to understand.
Pam in Seattle
Pat Stern on wed 31 dec 03
In the Nov./Dec. Clay Times Pete Pinnell mentions flocculating a glaze. I came across something by Linda Arbuckle recently where she mentions the same thing. Somehow or other I've never heard of flocculating glaze---and my main glaze-making I learned from Pete at a workshop at Anderson Ranch. Maybe he mentioned it then, but I was out of the room! What is this? How do you do it? Pat Stern Happy New Year, from Easton, PA More than happy--glorious, profitable, enlightening, on and on....!
Dave Finkelnburg on wed 31 dec 03
Dear Pat,
Your question is very simple. The answer...well...it's not so... :-)
For a useful, not complicated, discussion I suggest reading Ton Hansen's
comments at: http://www.digitalfire.ab.ca/cermat/education/130.php
Please note that Tony wisely suggests first trying to use kaolin, ball
clay or bentonite to some glaze suspension problems.
If that won't work, though, to "flocculate a glaze" you add something to
the glaze slurry to alter the slurry chemically and, as a result, keep the
glaze slurry from settling very fast, if at all. Most glaze flocculants
will not affect the color or surface of the fired glaze except by affecting
the handling and application properties of the glaze slurry. In other
words, most glaze flocculants do not affect the glaze, only the slurry of
glaze ingredients in water.
In the reference above, Tony Hansen says calcium chloride, Epsom salts,
and vinegar are potential glaze slurry flocculants. I have used vinegar
successfully. It is handy, and safe. Since it is a dilute acid, though, it
sometimes takes a lot, so you want to leave out or remove some water before
adding it to a glaze slurry. Now I use Epsom salts if I can't get clay or
bentonite to do the job.
One glaze flocculant that has been used with success by some potters is
muriatic acid. CAUTION: this is hydrochloric acid about 32% strength, and
should be used only with good goggles, rubber gloves and other protective
gear. This is potentially dangerous if you get it on your skin or in your
eyes!
Liz Willoughby reported in September using muriatic acid to flocculate a
troublesome, rapid-settling Tenmoku glaze. In February of 2001, Stephen
Grimmer posted, "If you have a glaze that settles badly from lots of soda
spar, frit, neph sy, or lack of clay, muriatic acid (HCl) will flocculate
the glaze and help keep it from forming a rock in the bottom of the bucket.
It also thickens the slop and helps application problems like running,
sheeting, and slow drying. I like to dilute it 1:1 with water (add acid to
water, not water to acid). Usually a tablespoon of the solution will
noticeably thicken 5 gallons of glaze."
Gerstley borate is the classic natural glaze flocculant. Even in small
quantities (above 5%) in a glaze, it can keep the glaze from settling rock
hard. In large quantities in a glaze, though, you have to add too much
water to thin down the "flocs" or clumps of glaze particles and thus have a
glaze that is too thin for some users.
The chemistry of glaze slurries that causes them to settle in a
troublesome way or remain suspended is complex and involved. Basically,
though, you have charged particles in the glaze slurry and the pH of the
slurry either permits these particles to settle hard or clump loosely
together and remain suspended. Adding one of the flocculants alters the
slurry pH. Testing a small quantity of glaze with one of the flocculants is
a good way of telling which and how much of the flocculant to use.
Good glazing!
Dave Finkelnburg in Idaho
----- Original Message -----
From: "Pat Stern"
Sent: Wednesday, December 31, 2003 8:23 AM
> In the Nov./Dec. Clay Times Pete Pinnell mentions flocculating a glaze. I
came across something by Linda Arbuckle recently where she mentions the same
thing. Somehow or other I've never heard of flocculating glaze---and my
main glaze-making I learned from Pete at a workshop at Anderson Ranch.
Maybe he mentioned it then, but I was out of the room! What is this? How
do you do it?
Ababi on thu 1 jan 04
In that book that had been too complicated for my poor English - Single
Firing, of Fran Tristram, was an excellent explanation about both
flocculants and defloculant. If you know English properly look for this
book just for the good explanation.
Ababi Sharon
Glaze addict
Kibbutz Shoval Israel
ababisha@shoval.org.il
http://ababi.active.co.il
http://www.matrix2000.co.nz/Matrix%20Demo/Ababi.htm
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of easley59
Sent: Thursday, January 01, 2004 9:38 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Flocculating glaze
Someone once explained floc vs de floc as: flocculating is like
gathering the flock, making the glaze thicker, molecules closer
together. De flocculating = making it looser, more watery, the flock
further apart, so to speak.
Simplistic, but easy to understand.
Pam in Seattle
________________________________________________________________________
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wayneinkeywest on thu 1 jan 04
Ababi:
You speak and understand better English than many of the people who live and
work in my town (and were born here.)
I wouldn't worry too much about it.
Some writers just can't write!
Wayne Seidl
> In that book that had been too complicated for my poor English - Single
> Firing, of Fran Tristram, was an excellent explanation about both
> flocculants and defloculant. If you know English properly look for this
> book just for the good explanation.
Ababi on fri 2 jan 04
Oh yes I know, it is a suburb of L/A. where you live "Seaton"- I have
many friend there!
Ababi
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of
wayneinkeywest
Sent: Friday, January 02, 2004 1:16 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Flocculating glaze
Ababi:
You speak and understand better English than many of the people who live
and
work in my town (and were born here.)
I wouldn't worry too much about it.
Some writers just can't write!
Wayne Seidl
> In that book that had been too complicated for my poor English -
Single
> Firing, of Fran Tristram, was an excellent explanation about both
> flocculants and defloculant. If you know English properly look for
this
> book just for the good explanation.
________________________________________________________________________
______
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.
Ababi on sat 3 jan 04
The speller killed my joke
Anyway, thank you for your warm words!
Ababi Sharon
Glaze addict
Kibbutz Shoval Israel
ababisha@shoval.org.il
http://ababi.active.co.il
http://www.matrix2000.co.nz/Matrix%20Demo/Ababi.htm
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Ababi
Sent: Friday, January 02, 2004 11:51 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Flocculating glaze
Oh yes I know, it is a suburb of L/A. where you live "Seaton"- I have
many friend there!
Ababi
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of
wayneinkeywest
Ababi:
You speak and understand better English than many of the people who live
and
work in my town (and were born here.)
I wouldn't worry too much about it.
Some writers just can't write!
Wayne Seidl
> In that book that had been too complicated for my poor English -
Single
> Firing, of Fran Tristram, was an excellent explanation about both
> flocculants and defloculant. If you know English properly look for
this
> book just for the good explanation.
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