Donna Kat on mon 13 nov 06
On Sun, 12 Nov 2006 22:49:58 -0500, Nancy
wrote:
>Hi Everyone. I just searched the archives for a problem I am still having
>with floating blue but am at a loss. I fire cone 6 oxidation and keep my
FB
>pieces on the cooler shelf. All of my pieces in this kiln came out
>beautiful with the exception of my floating blue and a mug on the shelf
with
>the floating blue pieces. I use chappells recipe and use GB.
>
>My FB pieces came out with many pinholes that were invisible at first
until
>I rubbed my hand over the piece then it was like static as the popped.
Now
>my second issue is where I double dipped the rims with a cream glaze and
>about 1/2" down the outside of the pots...no pinholes! The mug on the
shelf
>was dipped in Laguna's Layered fern which has been a stable glaze for me
but
>this time ithas pinholes justlike the floating blue pieces.
>
>So now I have a 5 gallon bucket of glaze that I can't use unless I can
find
>a fix for the problem...any suggestions?
>
>Thanks in advance and sorry for bringing up floating blue again.
>
>Nancy
>www.hilltoppottery.com
>
Was this a freshly mixed batch (the first time to be used)? If so was it
made with a new bag of Gerstley?
John Rodgers on mon 13 nov 06
Nancy,
Cone 6 is way to hot for Chappell's Floating Blue with GB.
FB is my major glaze. Have used it for years now with no problems,
basically. But this last round of pots, fired for the first time in my
new kilns, I got pits, pin holing, cratering, bloating ..... you name
it. I took a lot of pottery to the dump. My new kilns were firing too
hot. Cone 5 was actually cone 6, and for FB, that was way to hot and
created a lot of problems. I reset the temps on my computer controlled
kilns so the temp readout, actual temp, and the 5 cone all gave the same
message " We have arrived at CONE 5 and we are shutting down". Once I
did that, all my FB's are coming out beautiful once again.
I suspect there is nothing wrong with your FB glaze, but you are simply
firing way to hot. For me, FB works well at a COOL Cone 5 - horizontal
or even slightly above horizontal.
Good Luck.
Regards,
John Rodgers
Chelsea, AL
Nancy wrote:
> Hi Everyone. I just searched the archives for a problem I am still having
> with floating blue but am at a loss. I fire cone 6 oxidation and keep my FB
> pieces on the cooler shelf. All of my pieces in this kiln came out
> beautiful with the exception of my floating blue and a mug on the shelf with
> the floating blue pieces. I use chappells recipe and use GB.
>
> My FB pieces came out with many pinholes that were invisible at first until
> I rubbed my hand over the piece then it was like static as the popped. Now
> my second issue is where I double dipped the rims with a cream glaze and
> about 1/2" down the outside of the pots...no pinholes! The mug on the shelf
> was dipped in Laguna's Layered fern which has been a stable glaze for me but
> this time ithas pinholes justlike the floating blue pieces.
>
> So now I have a 5 gallon bucket of glaze that I can't use unless I can find
> a fix for the problem...any suggestions?
>
> Thanks in advance and sorry for bringing up floating blue again.
>
> Nancy
> www.hilltoppottery.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.
>
>
>
John Britt on mon 13 nov 06
Ron,
Bravo for posting the recipe.
I love it that you are finally on board with the short version of posting
recipes. I guess you really don't need the entire firing schedule, the
exp/cont., the thickness in mm, the sp. gr. etc. to help a poor soul with
a recipe!
Looking forward to the lifting of the ban,
John Britt
www.johnbrittpottery.com
Ron Roy wrote:
>Hi Nancy,
>
>Any new materials in that batch - wana try a floating blue without GB?
>
>Frit 3278- 35.
>Neph sye- 8.
>Custer spar- 12.5
>Dolomite-6.
>Whiting- 2.
>EPK- 26.
>Silica-10.5
>total-100.
>Cobalt carb-2.
>Red iron oxide-2.
>Rutile-3.75 up to 4. it says do a line blend we use 3.75 works for us!
>
>RR
>
Randy McCall on mon 13 nov 06
I use Chappells Floating Blue with cobalt carb all the time with no
pinholes. I usually fire to a Cone 6 or to a med cone 7 better. I also
substitute a ball clay for the kaolin. I would say it was underfired.
It just gets shiner and clearer the higher you fire it.
It refires even better.
Randy
South Carolina
Pottery Web site
http://members.tripod.com/~McCallJ/index.html
Cheryl Weickert6 on mon 13 nov 06
Ron, I gotta ask, does this glaze like a slow cool down or is it like the
regular FB? I know, test, test, test... just wondering if it was worth
trying as I usually go with the slow cool down and don't want to have to
do a whole kiln of fast cooling for just one glaze test!
Pinky... who likes the look of FB but not sure if I want to do a whole
kiln load of it!
On Tue, 14 Nov 2006 14:53:42 -0500, Ron Roy wrote:
>Hi Nancy,
>
>Any new materials in that batch - wana try a floating blue without GB?
>
>Frit 3278- 35.
>Neph sye- 8.
>Custer spar- 12.5
>Dolomite-6.
>Whiting- 2.
>EPK- 26.
>Silica-10.5
>total-100.
>Cobalt carb-2.
>Red iron oxide-2.
>Rutile-3.75 up to 4. it says do a line blend we use 3.75 works for us!
>
>RR
John Rodgers on tue 14 nov 06
Randy,
The reaction you get with Chappells Floating Blue is interesting ....
and opposite from my experience. There may be slight formulation
differences that make the difference.
I get the clean, pinhole free shiny glaze at the cool cone 5 temps.
Hotter and I get pin-holing. For you the reverse is true. It may be the
ball clay and the cobalt carbonate that make the difference. I use
Cobalt Oxide in place of the cobalt carb.
Regards,
John Rodgers
Chelsea, AL
Randy McCall wrote:
> I use Chappells Floating Blue with cobalt carb all the time with no
> pinholes. I usually fire to a Cone 6 or to a med cone 7 better. I also
> substitute a ball clay for the kaolin. I would say it was underfired.
> It just gets shiner and clearer the higher you fire it.
> It refires even better.
>
> Randy
> South Carolina
> Pottery Web site
>
> http://members.tripod.com/~McCallJ/index.html
>
> ______________________________________________________________________________
> 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 tue 14 nov 06
Dear Nancy ,
Your observation about the surface of a pot sounding like "Static" when =
you brushed your hand over the surface is interesting.
Are you sure that it is caused by breaking bubbles? Have you had a look =
at the surface under a times ten hand lens and seen and viewed small =
craters?
The reason I ask is because I have had similar experiences and I would =
like to know where the gas comes form to create these cavities,.
Best regards,
Ivor Lewis.
Redhill,
South Australia.
Ron Roy on tue 14 nov 06
Hi Nancy,
Any new materials in that batch - wana try a floating blue without GB?
Frit 3278- 35.
Neph sye- 8.
Custer spar- 12.5
Dolomite-6.
Whiting- 2.
EPK- 26.
Silica-10.5
total-100.
Cobalt carb-2.
Red iron oxide-2.
Rutile-3.75 up to 4. it says do a line blend we use 3.75 works for us!
RR
>Hi Everyone. I just searched the archives for a problem I am still having
>with floating blue but am at a loss. I fire cone 6 oxidation and keep my FB
>pieces on the cooler shelf. All of my pieces in this kiln came out
>beautiful with the exception of my floating blue and a mug on the shelf with
>the floating blue pieces. I use chappells recipe and use GB.
>
>My FB pieces came out with many pinholes that were invisible at first until
>I rubbed my hand over the piece then it was like static as the popped. Now
>my second issue is where I double dipped the rims with a cream glaze and
>about 1/2" down the outside of the pots...no pinholes! The mug on the shelf
>was dipped in Laguna's Layered fern which has been a stable glaze for me but
>this time ithas pinholes justlike the floating blue pieces.
>
>So now I have a 5 gallon bucket of glaze that I can't use unless I can find
>a fix for the problem...any suggestions?
>
>Thanks in advance and sorry for bringing up floating blue again.
>
>Nancy
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Ron Roy on wed 15 nov 06
Hi Cheryl,
I don't use that glaze - I fire at cone 10 - I do know that it works
because others have tested it at cone 6 and it seems to work just fine.
I don't know why some people have trouble and have to fire the original
lower - perhaps local water supplies add something?
I think the current supply of GB is different than the older supplies - I
do know that Laguna stopped giving analysis for it - I don't know why.
I am sure a slow cool down will make a difference - it may be better - or
just different - tell us what happens.
RR
>Ron, I gotta ask, does this glaze like a slow cool down or is it like the
>regular FB? I know, test, test, test... just wondering if it was worth
>trying as I usually go with the slow cool down and don't want to have to
>do a whole kiln of fast cooling for just one glaze test!
>
>Pinky... who likes the look of FB but not sure if I want to do a whole
>kiln load of it!
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Nancy on wed 15 nov 06
I took my floating blue bad mugs with me today to my supplier who has
been a tremendous help to me when I've asked questions. He took a good
look at it and thinks my problem may be underfiring of FB. Then I
realized that my FB on my top shelf on Miller 50 did NOT pinhole. Same
kiln but top shelf is a true cone 6. Different clay body....I use
Laguna's 66 and miller 50. The 66 pinholed and then I noticed a few
small pinholes on my other 66 pieces. Now I'm wondering...is it the
Laguna 66 clay. A fellow potter is sending me some samples of her
different cone 6's so I can test my FB on it and see if the problem is
the clay. I picked up the chemicals RR posted in his revised version of
FB and am going to try that on the 66 since it's my main clay in the studio.
If a piece is overfired....the blisters are larger and underfired they
are like pinholes but not truly pinholes, they are little bubbles that
burst when you rub them. Those are the type I have. I'm now going to
try and refire them at the higher temp and see if it fixes theproblem.
Any input?
Nancy
www.hilltoppottery.com
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