Antoinette Badenhorst on wed 11 jan 06
Does anyone know what exactly happens when vinegar is used to fix cracks?
Sometimes it works and other times with different clays it does not work.
Any specific scientific explanations to share please? Thanks.
Do you need sharp trimming tools that will not wear out quickly? Contact me
for information.
Antoinette Badenhorst
105 Westwood Circle
Saltillo MS, 38866
662 869 1651
www.clayandcanvas.com
www.southernartistry.org
Antoinette Badenhorst on thu 12 jan 06
Okay, here is my guess on this; Vinegar deflocculates the clay and the =
clay
particles mingle then "across the crack". What I found is that more =
plastic
and less "open" clay does not respond well to this treatment of a crack. =
Is
it possible that it is more difficult to break the magnetic fields =
around
more plastic clay? I realize I am gurgling here. Ron, David Ivor....?
Do you need sharp trimming tools that will not wear out quickly? Contact =
me
for information.=20
Antoinette Badenhorst
105 Westwood Circle
Saltillo MS, 38866
662 869 1651
www.clayandcanvas.com
www.southernartistry.org
=20
=20
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Antoinette
Badenhorst
Sent: Wednesday, January 11, 2006 10:04 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: What happens when vinegar fixes cracks?
Does anyone know what exactly happens when vinegar is used to fix =
cracks?
Sometimes it works and other times with different clays it does not =
work.
Any specific scientific explanations to share please? Thanks.
Do you need sharp trimming tools that will not wear out quickly? Contact =
me
for information.
Antoinette Badenhorst
105 Westwood Circle
Saltillo MS, 38866
662 869 1651
www.clayandcanvas.com
www.southernartistry.org
_________________________________________________________________________=
___
__
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Vince Pitelka on thu 12 jan 06
Antoinette wrote:
"Okay, here is my guess on this; Vinegar deflocculates the clay and the clay
particles mingle then "across the crack". What I found is that more plastic
and less "open" clay does not respond well to this treatment of a crack. Is
it possible that it is more difficult to break the magnetic fields around
more plastic clay? I realize I am gurgling here.?"
Antoinette -
Except that vinegar is a flocculant, not a deflocculant. It causes the
particles to attract one another, and that seems to strengthen the repair.
I really do not know why it works so well, but it sure does.
- 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/
Jim Murphy on fri 13 jan 06
Hi Antoinette,
Kaolinite particles, in water [H2O], are 1:1 sheet silicates with two planar
surface layers [positively-charged Al2(OH)4 and negatively-charged Si2O5
over a broad pH range] and with particle "edges" composed of a mixture of
alumina and silica sites.
The particle "edges" may be net positively or negatively-charged dependent
on pH.
Vinegar, being an "acid" [pH less than 7] would tend to make the "edges" net
positively-charged. [The "edges" would tend to be negatively-charged in an
alkaline solution, i.e. pH over 7].
In your crack-fixing scenario, vinegar may cause a "localized" flocculating
effect, creating stronger edge-to-surface clay particle contacts.
Admittedly, the above is overly simplistic when comparing different
clay-bodies though, where there's usually other particle interactions
[feldspar, free-silica, 2:1 silicate materials, etc.] which may behave
differently [from pure kaolinite particles] with change of pH.
Hope this helps.
Best wishes,
Jim Murphy
Antoinette Badenhorst on fri 13 jan 06
Jim Thanks for your answer. It makes sense to me what you say. It would =
be
interesting to test this scenario with, other deflocculating agents as
someone else suggested. I remember years ago I've done a project with
casting slip and I studied the + and - charged particles in order to
understand what I was doing. I started using vinegar to fix cracks on
Southern Ice, but I find that I have to dilute the vinegar, since it =
makes a
bubbling mess on the SI and although it do fix the crack, the results =
are
not satisfactory.
Ivor I checked the archives, but could not find your answer there. I =
have a
daughter that is almost brilliant in some thins she do, but when it =
comes to
searching, she is very quickly to say..."I can not find it". Maybe she =
got
it from me!
Do you need sharp trimming tools that will not wear out quickly? Contact =
me
for information.=20
Antoinette Badenhorst
105 Westwood Circle
Saltillo MS, 38866
662 869 1651
www.clayandcanvas.com
www.southernartistry.org
=20
=20
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Jim Murphy
Sent: Friday, January 13, 2006 12:57 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: What happens when vinegar fixes cracks?
Hi Antoinette,
Kaolinite particles, in water [H2O], are 1:1 sheet silicates with two =
planar
surface layers [positively-charged Al2(OH)4 and negatively-charged Si2O5
over a broad pH range] and with particle "edges" composed of a mixture =
of
alumina and silica sites.
The particle "edges" may be net positively or negatively-charged =
dependent
on pH.
Vinegar, being an "acid" [pH less than 7] would tend to make the "edges" =
net
positively-charged. [The "edges" would tend to be negatively-charged in =
an
alkaline solution, i.e. pH over 7].
In your crack-fixing scenario, vinegar may cause a "localized" =
flocculating
effect, creating stronger edge-to-surface clay particle contacts.
Admittedly, the above is overly simplistic when comparing different
clay-bodies though, where there's usually other particle interactions
[feldspar, free-silica, 2:1 silicate materials, etc.] which may behave
differently [from pure kaolinite particles] with change of pH.
Hope this helps.
Best wishes,
Jim Murphy
_________________________________________________________________________=
___
__
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You may look at the archives for the list or change your subscription
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Ivor and Olive Lewis on fri 13 jan 06
Dear Antoinette Badenhorst,
Though the idea of deflocculating the clay with vinegar is attractive it =
does nothing to address the other half of your question, which is why it =
works with some clay bodies but not others.
Best regards,
Ivor
Ivor and Olive Lewis on fri 13 jan 06
Dear Antoinette '
You ask ...to fix cracks?
Sometimes it works and other times with different clays it does not =
work.
Any specific scientific explanations to share please? Thanks.>....
Presuming you mean on dry greenware ? The short answer is "No". Just =
seems to be one of those things that works. But I think I did suggest a =
reason I can no longer recall some time ago. That answer may be in the =
archives.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
dalecochoy on sat 14 jan 06
Uhhh, yea Jim , what you said...:>) :>)
You know, I've NEVER had any kind of successful track record fixing cracks
in bisque with ANY methods I'd ever seen or mixtures,none of vinegar, etc.
mixes ever did. Wasted a lot of time. until I started doing this:
I dry and powder some of the clay.
I mix with pancake syrup and shredded toilet paper.
apply up to several coats.
Can sand a bit if needed when dry.
Cover the piece in plastic until the joint is dry..
Almost always works, '
Besides, it smells like a nice batch of cookies when bisqueing :>)
Dale
----- Original Message -----
From: "Jim Murphy"
To:
Sent: Friday, January 13, 2006 1:56 AM
Subject: Re: What happens when vinegar fixes cracks?
> Hi Antoinette,
>
> Kaolinite particles, in water [H2O], are 1:1 sheet silicates with two
> planar
> surface layers [positively-charged Al2(OH)4 and negatively-charged Si2O5
> over a broad pH range] and with particle "edges" composed of a mixture of
> alumina and silica sites.
>
> The particle "edges" may be net positively or negatively-charged dependent
> on pH.
>
> Vinegar, being an "acid" [pH less than 7] would tend to make the "edges"
> net
> positively-charged. [The "edges" would tend to be negatively-charged in an
> alkaline solution, i.e. pH over 7].
>
> In your crack-fixing scenario, vinegar may cause a "localized"
> flocculating
> effect, creating stronger edge-to-surface clay particle contacts.
>
> Admittedly, the above is overly simplistic when comparing different
> clay-bodies though, where there's usually other particle interactions
> [feldspar, free-silica, 2:1 silicate materials, etc.] which may behave
> differently [from pure kaolinite particles] with change of pH.
>
> Hope this helps.
>
> Best wishes,
>
> Jim Murphy
Ivor and Olive Lewis on sat 14 jan 06
I have a feeling that this has very little to do with the clay fractions =
in the dry Greenware and a lot to do with the nature of Vinegar.
In addition, I repeat that any proposal has to address the failures as =
well as the success of this solution to repairing cracks.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Antoinette Badenhorst on sun 15 jan 06
Well Ivor, let's pull this apart then. If we can find all the answers, =
then
maybe we change clay forever. Lets start asking the question of what =
makes
vinegar different from water?
Do you need sharp trimming tools that will not wear out quickly? Contact =
me
for information.=20
Antoinette Badenhorst
105 Westwood Circle
Saltillo MS, 38866
662 869 1651
www.clayandcanvas.com
www.southernartistry.org
=20
=20
-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Ivor and =
Olive
Lewis
Sent: Saturday, January 14, 2006 1:04 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: What happens when vinegar fixes cracks?
I have a feeling that this has very little to do with the clay fractions =
in
the dry Greenware and a lot to do with the nature of Vinegar.
In addition, I repeat that any proposal has to address the failures as =
well
as the success of this solution to repairing cracks.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
_________________________________________________________________________=
___
__
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.
Ivor and Olive Lewis on mon 16 jan 06
Dear Antoinette Badenhorst,
<then maybe we change clay forever. Lets start asking the question of =
what makes vinegar different from water?>>
Acetic Acid. It is a solid compound at temperatures below 20 deg =
Celsius. So when the water has evaporated from it acts as a cementing =
agent for the other dry particles. Vinegar is 3 to 5 % Acetic acid.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
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