Jim Larkin on fri 26 jul 02
any
silica. Perhaps you are confusing it with the opacifier Zircopax which =
is
zirconium silicate. Zirconium oxide is available from Standard Clays in
Philadelphia.
A friend of mine coated the soft bricks in her wood kiln with Zircon.>
Ruth,
Actually, zircon is ziroconium silicate. Zircopax, superpax, etc. are =
all zircons. I think that confuses people often. Zirconia is zirconium =
oxide. That confusion prompted my question as to whether anyone had used =
a zirconium oxide wash, and what might be the result if they used a =
zirconium silicate wash instead. The names get confused in the =
literature, and people must have done so. If your friend used zircon =
instead of zirconia, that might explain its poor performance. I am =
particularly concerned what the zirconium silicate wash would do in a =
salt fire.
Ruggles and Rankin use an alumina hydrate wash on the hard brick, and a =
zirconia wash on the soft. We are just finishing a 2 chambered =
wood/salt, and gathering information on washes and weighing our options. =
ITC is certainly a consideration.
I'm glad to know that zirconium oxide is available from Standard. Thanks =
for the input.
Regards,
Jim
Jim Larkin
Fox Pass Pottery
379 Fox Pass
Hot Springs, Arkansas
71901
foxpass@aristotle.net
Jim Larkin on fri 26 jul 02
Ruggles and Rankin recommend a zirconia wash for soft brick in wood/salt =
firing. At one point they, inadvertantly I suppose, say zircon instead =
of zirconia. Have any of you used zirconia as a wash for soft brick, and =
have you ever substituted zircon for zirconia? I would assume the =
silica content of zircon would attract the sodium from salt, rather than =
act as a wash/protector. Any experiences here?
Also, any sources for zirconia? None of my regular suppliers carry it.
Thanks,
Jim
Jim Larkin
Fox Pass Pottery
379 Fox Pass
Hot Springs, Arkansas
71901
foxpass@aristotle.net
Ruth Ballou on fri 26 jul 02
Jim,
Zircon is a trade name for zirconium oxide and thus does not contain any
silica. Perhaps you are confusing it with the opacifier Zircopax which is
zirconium silicate. Zirconium oxide is available from Standard Clays in
Philadelphia.
A friend of mine coated the soft bricks in her wood kiln with Zircon.
However, this was after the Green Patch coating had started to flake off,
making a bit of a mess. The areas that were successfully re-
coated with the Zircon seemed to do a bit better than raw soft brick, but
not significantly so. Perhaps one of the ITC coatings would be a better
choice.
Ruth Ballou
Silver Spring, MD
>Ruggles and Rankin recommend a zirconia wash for soft brick in wood/salt
>firing. At one point they, inadvertantly I suppose, say zircon instead of
>zirconia. Have any of you used zirconia as a wash for soft brick, and have
>you ever substituted zircon for zirconia? I would assume the silica
>content of zircon would attract the sodium from salt, rather than act as a
>wash/protector. Any experiences here?
>
>Also, any sources for zirconia? None of my regular suppliers carry it.
>
>Thanks,
> Jim
>
>Jim Larkin
>Fox Pass Pottery
>379 Fox Pass
>Hot Springs, Arkansas
>71901
>foxpass@aristotle.net
>
>______________________________________________________________________________
>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.
Ruth Ballou on sat 27 jul 02
Jim,
Count me among the confused.... now unconfused. Thank you all for the
correction. Now to further clarity the rest of my post. At the time of its
building, Douglas and Will recommend Green Patch for the soft brick in her
kiln.... this after we were all fresh from the kiln building workshop for
the noborigama at Peter's Valley. The Green Patch deteriorated pretty
quickly, taking chunks of soft brick with it. Thus, the zirconia wash (yes,
I'm sure it was the oxide; I checked!) after further consulation with them.
It did not prove to be a whole lot better than the soft brick alone.
However, that does not mean we were disappointed in its performance.
Rather, we were quite surprised as to how well the soft brick held up to
the salt and ash with no coating at all. We're not the only ones to have
observed this.There is an article in the April 1982 Ceramics Monthly by
Anne Shattuck on her soft brick salt kiln. Her kiln was also was coated
with Green Patch, which did not hold. The article says that she found that
the unprotected soft brick attracted little salt and did not corrode as
expected. The kiln was constructed of K-23 soft brick. This could be tested
easily by putting a couple of uncoated soft bricks in a firing.
I recently tore down a twenty year old hard brick wood/salt kiln which had
no coatings. The interior, of course was well coated with salt build up.
However, it came down very easily, and the arch bricks, except for the salt
on the interior face, looked brand new and could have been reused.
For information on other coatings..... you might try contacting Donovan
Palmquist at Master Kiln Builders for his input.
Ruth Ballou
Silver Spring, MD
> >silica. Perhaps you are confusing it with the opacifier Zircopax which is
>zirconium silicate. Zirconium oxide is available from Standard Clays in
>Philadelphia.
>
>A friend of mine coated the soft bricks in her wood kiln with Zircon.>
>
>Ruth,
>Actually, zircon is ziroconium silicate. Zircopax, superpax, etc. are all
>zircons. I think that confuses people often. Zirconia is zirconium oxide.
>That confusion prompted my question as to whether anyone had used a
>zirconium oxide wash, and what might be the result if they used a
>zirconium silicate wash instead. The names get confused in the literature,
>and people must have done so. If your friend used zircon instead of
>zirconia, that might explain its poor performance. I am particularly
>concerned what the zirconium silicate wash would do in a salt fire.
>
>Ruggles and Rankin use an alumina hydrate wash on the hard brick, and a
>zirconia wash on the soft. We are just finishing a 2 chambered wood/salt,
>and gathering information on washes and weighing our options. ITC is
>certainly a consideration.
>
>I'm glad to know that zirconium oxide is available from Standard. Thanks
>for the input.
>
>Regards,
> Jim
>
>Jim Larkin
>Fox Pass Pottery
>379 Fox Pass
>Hot Springs, Arkansas
>71901
>foxpass@aristotle.net
>
>______________________________________________________________________________
>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.
Joyce Lee on sat 27 jul 02
> I have seen ITC coatings talked about. What is the formula for an ITC
> shelf coating?
>
> Barb
---------------------------------------------------
ITC is a commercial product and, as with all such products of which I'm
aware, the formula is not available to the public.
Joyce
In the Mojave
Michael Banks on sat 27 jul 02
Zircon (zirconium silicate -ZrSiO4) is a natural mineral won from beach
sands and the principle ore for the production of zirconium metal and
zirconia. It is less refractory than zirconia, melting at ~2550 degrees C.
Zircon contains 32.8% silica -as Jim Larkin correctly noted. The name
"zircon" is ancient, possibly derived from the Persian; circa 2500 years
ago.
Zirconia is pure zirconium oxide (ZrO2), and has a melting point of 2750
degrees C. It is one of the most refractory materials known.
Zircon is preferentially attacked by hot alkali, compared to zirconia.
Zirconia should make a good kiln wash, only bettered by thoria (ThO2), which
has an even higher melting point. Thoria is expensive and radioactive
though, usually putting it out of bounds.
Michael,
in NZ
----- Original Message -----
Ruth Ballou wrote:
> Zircon is a trade name for zirconium oxide and thus does not contain any
> silica. Perhaps you are confusing it with the opacifier Zircopax which is
> zirconium silicate. Zirconium oxide is available from Standard Clays in
> Philadelphia.
>
> A friend of mine coated the soft bricks in her wood kiln with Zircon.
> However, this was after the Green Patch coating had started to flake off,
> making a bit of a mess. The areas that were successfully re-
> coated with the Zircon seemed to do a bit better than raw soft brick, but
> not significantly so. Perhaps one of the ITC coatings would be a better
> choice.
>
> Ruth Ballou
> Silver Spring, MD
>
>
> >Ruggles and Rankin recommend a zirconia wash for soft brick in wood/salt
> >firing. At one point they, inadvertantly I suppose, say zircon instead of
> >zirconia. Have any of you used zirconia as a wash for soft brick, and
have
> >you ever substituted zircon for zirconia? I would assume the silica
> >content of zircon would attract the sodium from salt, rather than act as
a
> >wash/protector. Any experiences here?
> >
> >Also, any sources for zirconia? None of my regular suppliers carry it.
> >
> >Thanks,
> > Jim
> >
> >Jim Larkin
> >Fox Pass Pottery
> >379 Fox Pass
> >Hot Springs, Arkansas
> >71901
> >foxpass@aristotle.net
> >
>
>___________________________________________________________________________
___
> >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.
>
>
____________________________________________________________________________
__
> 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.
Barbara Mueller on sat 27 jul 02
I have seen ITC coatings talked about. What is the formula for an ITC
shelf coating?
Barb
-----Original Message-----
From: Ceramic Arts Discussion List [mailto:CLAYART@LSV.CERAMICS.ORG] On
Behalf Of Ruth Ballou
Sent: Friday, July 26, 2002 12:11 PM
To: CLAYART@LSV.CERAMICS.ORG
Subject: Re: Zirconia wash
Jim,
Zircon is a trade name for zirconium oxide and thus does not contain any
silica. Perhaps you are confusing it with the opacifier Zircopax which
is
zirconium silicate. Zirconium oxide is available from Standard Clays in
Philadelphia.
A friend of mine coated the soft bricks in her wood kiln with Zircon.
However, this was after the Green Patch coating had started to flake
off,
making a bit of a mess. The areas that were successfully re-
coated with the Zircon seemed to do a bit better than raw soft brick,
but
not significantly so. Perhaps one of the ITC coatings would be a better
choice.
Ruth Ballou
Silver Spring, MD
>Ruggles and Rankin recommend a zirconia wash for soft brick in
wood/salt
>firing. At one point they, inadvertantly I suppose, say zircon instead
of
>zirconia. Have any of you used zirconia as a wash for soft brick, and
have
>you ever substituted zircon for zirconia? I would assume the silica
>content of zircon would attract the sodium from salt, rather than act
as a
>wash/protector. Any experiences here?
>
>Also, any sources for zirconia? None of my regular suppliers carry it.
>
>Thanks,
> Jim
>
>Jim Larkin
>Fox Pass Pottery
>379 Fox Pass
>Hot Springs, Arkansas
>71901
>foxpass@aristotle.net
>
>_______________________________________________________________________
_______
>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.
________________________________________________________________________
______
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.
Leland G. Hall on mon 29 jul 02
On Sat, 27 Jul 2002 10:13:11 -0700, Joyce Lee wrote:
>> I have seen ITC coatings talked about. What is the formula for an ITC
>> shelf coating?
>>
>> Barb
>---------------------------------------------------
>ITC is a commercial product and, as with all such products of which I'm
>aware, the formula is not available to the public.
>
>Joyce
>In the Mojave
>
>___________________________________________________________________________
___
>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.
Yes, ITC is a comercial product that from what I have heard works really
well, and is also too darned expesive for my meager budget. But the
question of formula is a darned good one. I'd bet it's fairly simple.
Maybe someone ought to analyze a sample. I'd love to make to own. Is this
legal? Any thoughts?
Leland Hall
Before The Wheel Enterprises
La Pine, Oregon
Tommy Humphries on mon 29 jul 02
For those interested, ceramic industry had a good article in it on ceramic
coatings back in may...you can read up on it here
http://www.ceramicindustry.com/ci/cda/articleinformation/features/bnp__featu
res__item/0,2710,77398,00.html
It describes how these coating work...It doesn't go into specifics on the
materials used but it is an interesting article
Tommy
----- Original Message -----
From: "Leland G. Hall"
To:
Sent: Sunday, July 28, 2002 11:54 PM
Subject: Re: Zirconia wash
> On Sat, 27 Jul 2002 10:13:11 -0700, Joyce Lee wrote:
>
> >> I have seen ITC coatings talked about. What is the formula for an ITC
> >> shelf coating?
> >>
> >> Barb
> >---------------------------------------------------
> >ITC is a commercial product and, as with all such products of which I'm
> >aware, the formula is not available to the public.
> >
> >Joyce
> >In the Mojave
> >
>
>___________________________________________________________________________
> ___
> >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.
>
> Yes, ITC is a comercial product that from what I have heard works really
> well, and is also too darned expesive for my meager budget. But the
> question of formula is a darned good one. I'd bet it's fairly simple.
> Maybe someone ought to analyze a sample. I'd love to make to own. Is
this
> legal? Any thoughts?
>
> Leland Hall
> Before The Wheel Enterprises
> La Pine, Oregon
>
>
____________________________________________________________________________
__
> 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.
>
Leland G. Hall on tue 30 jul 02
Thanks Tommy That looks interesting, but when I tried the link you
kindly provided, I could not get in. Don't know if it's me or your link.
Could you check on that for us? Maybe I'm doing something wrong. Thanks
again.
Leland Hall
Before The Wheel Enterprises
La Pine, Oregon
On Mon, 29 Jul 2002 19:05:33 -0500, Tommy Humphries
wrote:
>For those interested, ceramic industry had a good article in it on ceramic
>coatings back in may...you can read up on it here
>http://www.ceramicindustry.com/ci/cda/articleinformation/features/bnp__feat
u
>res__item/0,2710,77398,00.html
>
>It describes how these coating work...It doesn't go into specifics on the
>materials used but it is an interesting article
>
>Tommy
>
>
>----- Original Message -----
>From: "Leland G. Hall"
>To:
>Sent: Sunday, July 28, 2002 11:54 PM
>Subject: Re: Zirconia wash
>
>
>> On Sat, 27 Jul 2002 10:13:11 -0700, Joyce Lee
wrote:
>>
>> >> I have seen ITC coatings talked about. What is the formula for an ITC
>> >> shelf coating?
>> >>
>> >> Barb
>> >---------------------------------------------------
>> >ITC is a commercial product and, as with all such products of which I'm
>> >aware, the formula is not available to the public.
>> >
>> >Joyce
>> >In the Mojave
>> >
>>
>>__________________________________________________________________________
_
>> ___
>> >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.
>>
>> Yes, ITC is a comercial product that from what I have heard works really
>> well, and is also too darned expesive for my meager budget. But the
>> question of formula is a darned good one. I'd bet it's fairly simple.
>> Maybe someone ought to analyze a sample. I'd love to make to own. Is
>this
>> legal? Any thoughts?
>>
>> Leland Hall
>> Before The Wheel Enterprises
>> La Pine, Oregon
>>
>>
>___________________________________________________________________________
_
>__
>> 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.
>>
>
>___________________________________________________________________________
___
>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.
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