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single firing question

updated mon 25 jan 10

 

Sumi von Dassow on sat 23 jan 10


Cathi

I use melted paraffin to wax my feet also, and I have dipped bone dry
green-ware into the hot paraffin with no ill effects. Dry clay doesn't
disintegrate in wax. I don't single-fire, so I can't address the rest of
your question other than to offer the opinion that a coat of wax on the
foot might act to protect the foot and keep it from cracking from having
wet glaze poured into it.

Sumi
> I'm wanting to explore single firing and to that end have all my test
> "tiles" (OK, shot glasses) lined up and ready to glaze.
> Here's the question...
> Is there a recommended way to wax the bottoms?
> I typically use an electric skillet with melted wax to coat the foot of
> my bisqueware, but my instinct tells me that setting bone dry greenware
> into a vat of liquid paraffin will #1 disintegrate the greenware and #2
> create problems with the glaze and body drying properly.
> Hmmmm.
>
> I've not been able to find too much on the 'net about the process.
> All tips are greatly appreciated!
>
> --
> Cathi Newlin, Angels Camp, Ca
> cathi@box49.com
> box49@caltel.com
> cathi@SquarePegArts.com
> -------------------------------
> California Boxers in Need:
> http://CaliforniaBoxer.org
>
>

gary navarre on sat 23 jan 10


Hay Folks,

When I test glaze I don't make just a couple tiles either but a bunch of s=
omething useful. However, I don't use wax! With enough practice I learned t=
o glaze without ending up with pots glaze stuck to shelves. In fact, when I=
get to glazing I'm not vary picky and some always gets on the foot so I ju=
st clean it off with a damp sponge. Make sure you wash the sponge a lot and=
wipe the foot ring up to about 1/8 inch. Unless you are using some real es=
oteric crystalline glaze that has a sensitive melting point I'd bet most re=
cipes will fire to a cone or two more and not run too much. That is a diffe=
rent story of you are concocting your own from scratch so put a glaze you t=
hink might run a lot inside a bowl to see before glazing a vertical piece. =
You can also glaze the lower part of the pot (test tile) with a thinner coa=
t of glaze so it won't have enough to flow to the shelf. A third of the way=
up a second layer and a third above that. Just learn to glaze
thinner near the foot ring. If wiping makes the foot slightly rougher I'll=
wait till fired and hand sand with a stone (chip of kiln shelf). I always =
run a chip around the bottom of a piece when I bring it out of the kiln.

John "Jack" Foster introduced me to once fire glazing when he taught us ab=
out engobes in 1963 at The Center for Creative Studies (known as "Arts & Cr=
afts" to old-timers) in Detroit. I saw the advantages so that is how I appr=
oach making, glazing, and firing. I designed two feet into my work, the tri=
mmed foot ring to float a piece above the ground and a slight shadow line f=
or pieces that seem to grow out of the ground. Either one can be a challeng=
e with porcelain and a dark glaze because of the annoying contrast if too m=
uch porcelain shows. I guess I like living on the edge too because I don't =
stilt my wood-fired stuff with wads or seashells either and rely on a coupl=
e of thin coats of kiln wash to protect me.

Just a different way of doing things so stay in there and don't let me cha=
nge ya eh!

Gary Navarre
Navarre Pottery
Navarre Enterprises
Norway, Michigan, USA
http://www.youtube.com/GindaUP
http://public.fotki.com/GindaUP/


--- On Sat, 1/23/10, Cathi Newlin wrote:

> From: Cathi Newlin
> Subject: [Clayart] Single Firing question
> To: Clayart@LSV.CERAMICS.ORG
> Date: Saturday, January 23, 2010, 1:21 PM
> I'm wanting to explore single firing
> and to that end have all my test
> "tiles" (OK, shot glasses) lined up and ready to glaze.
> Here's the question...
> Is there a recommended way to wax the bottoms?
> I typically use an electric skillet with melted wax to coat
> the foot of
> my bisqueware, but my instinct tells me that setting bone
> dry greenware
> into a vat of liquid paraffin will #1 disintegrate the
> greenware and #2
> create problems with the glaze and body drying properly.
> Hmmmm.
>
> I've not been able to find too much on the 'net about the
> process.
> All tips are greatly appreciated!
>
> --
> Cathi Newlin, Angels Camp, Ca
> cathi@box49.com
> box49@caltel.com
> cathi@SquarePegArts.com
> -------------------------------
> California Boxers in Need:
> http://CaliforniaBoxer.org
>

Cathi Newlin on sat 23 jan 10


I'm wanting to explore single firing and to that end have all my test
"tiles" (OK, shot glasses) lined up and ready to glaze.
Here's the question...
Is there a recommended way to wax the bottoms?
I typically use an electric skillet with melted wax to coat the foot of
my bisqueware, but my instinct tells me that setting bone dry greenware
into a vat of liquid paraffin will #1 disintegrate the greenware and #2
create problems with the glaze and body drying properly.
Hmmmm.

I've not been able to find too much on the 'net about the process.
All tips are greatly appreciated!

--
Cathi Newlin, Angels Camp, Ca
cathi@box49.com
box49@caltel.com
cathi@SquarePegArts.com
-------------------------------
California Boxers in Need:
http://CaliforniaBoxer.org

marci and rex on sat 23 jan 10


At 01:21 PM 1/23/2010, Cathi Newlin wrote:
>I'm wanting to explore single firing and to that end have all my test
>"tiles" (OK, shot glasses) lined up and ready to glaze.
>Here's the question...
>Is there a recommended way to wax the bottoms?
>I typically use an electric skillet with melted wax to coat the foot of
>my bisqueware, but my instinct tells me that setting bone dry greenware
>into a vat of liquid paraffin will #1 disintegrate the greenware and #2
>create problems with the glaze and body drying properly.
>Hmmmm.
>
>I've not been able to find too much on the 'net about the process.
>All tips are greatly appreciated!
>


Hi Cathi ,
I once fire ^6 porcelain .. I do some with a commercial clear
glaze and some with underglaze under the commercial clear.. I brush
on the glaze rather than dip ...but I have done some vases
and such where I have brushed on liquid wax onto the bases ...
and also I water down the underglazes a lot when I apply them
for a watercolor sort of finish ... and the clay doesnt disintegrate ..
The one time I had a problem with bloating was when I glazed the
inside and outside of a vase in quick succession .. The vase
didnt collapse but it did bloat ...Now, I glaze the
inside first, let it dry , then I glaze the outside..
It did also take some experimenting to find out how thickly to
glaze the pieces.. I discovered that , contrary to most of
the advice I was given ( including from Duncan, whose clear glaze
I was using at the time.. I now use Amaco ) , I had to lay
the glaze on thicker... 1 or 2 coats over the embossed
edges and 2 -3 in the center areas where Im going to china
paint in later fires... If I apply the glaze too thin , I get
pinholes and craters..
Also, lightly misting the dry clay with water before glazing
helps with the pinhole issue ..
The best advice I can give is fire very slowly ... It takes me
about 15 hours to fire ... ( which is really probably about
the same time it would take to bisque fire and then glaze fire
but I dont have to unload the kiln and load it again .. saves my
back .. AND time )
If youre doing porcelain , ILl be glad to share the firing
schedule I use ( I am still working on tweaking it to get it down
in time but still maintaining the results.. )
Marci the chinapainter

Snail Scott on sat 23 jan 10


On Jan 23, 2010, at 1:21 PM, Cathi Newlin wrote:

> I'm wanting to explore single firing...
> I typically use...melted wax to coat the foot of
> my bisqueware, but my instinct tells me that setting bone dry
> greenware
> into a vat of liquid paraffin will #1 disintegrate the greenware and
> #2
> create problems with the glaze and body drying properly...


Though I don't do pottery, I've used both hot wax and
wax emulsion on greenware with no problems. In my
experience, it's the water in the glaze that's the danger
in green glazing. Wax doesn't really cause any trouble.

Your #1 hypothetical just doesn't seem to happen.
As for #2, it will dry pretty much the same as it would
sitting on an impervious surface; i.e. extra drying or
candling time to be sure it's not damp. Still, all we're
talking about is the absorbed glaze water - not a lot,
and a decent candling period should do the trick.

-Snail

Paul Herman on sat 23 jan 10


Cathi,

I don't think the hot wax will make your clay fall apart. It just
takes a quick dip to coat the bottom. It also won't interfere with the
drying, in my experience, though I generally use wax emulsion, not hot.

There is a good book on the subject by Dennis Parks, A Potter's Guide
to Raw Glazing and Oil Firing. I have used his method of glazing bone
dry ware, just do the outside and inside as closely together in time
as you can, so as to equalize the expansion that takes place when you
wet the raw clay.

Best wishes,

Paul Herman

Great Basin Pottery
Doyle, California US
www.greatbasinpottery.com/




On Jan 23, 2010, at 11:21 AM, Cathi Newlin wrote:

> I'm wanting to explore single firing and to that end have all my test
> "tiles" (OK, shot glasses) lined up and ready to glaze.
> Here's the question...
> Is there a recommended way to wax the bottoms?
> I typically use an electric skillet with melted wax to coat the foot
> of
> my bisqueware, but my instinct tells me that setting bone dry
> greenware
> into a vat of liquid paraffin will #1 disintegrate the greenware and
> #2
> create problems with the glaze and body drying properly.
> Hmmmm.
>
> I've not been able to find too much on the 'net about the process.
> All tips are greatly appreciated!
>
> --
> Cathi Newlin, Angels Camp, Ca
> cathi@box49.com
> box49@caltel.com
> cathi@SquarePegArts.com
> -------------------------------
> California Boxers in Need:
> http://CaliforniaBoxer.org

Mike on sun 24 jan 10


Hello Cathi,

Though I don't have personal experience with paraffin, my 'gut' tells me
that you'll be ok with it. I'm sure someone on the list with experience
here can chime in, but if you are still worried, you can try a brush on
latex or water repellent. In Japanese it's called hassuizai, I don't
know what to call it in English, but it works equally well to treat your
car windshield to make water bead and run off the glass, and lasts
longer than Rain-X type products. Anyway, either will prevent glaze
getting on the bottoms and brushes on easily to greenware. I've tried
both and prefer the water repellant. I use very open clay, and have had
no problems, as long as I don't get overly aggressive loading the brush
or go over the same area too much at once.

Good luck,

Mike

Mike
in Taku, Japan

http://karatsupots.com
http://karatsupots.blogspot.com

Kiln Building Workshop, Oct. 15 - 22

http://karatsupots.com/workshop2010/workshop2010.html
http://karatsupots-workshop.blogspot.com/



Cathi Newlin ????????:
> I'm wanting to explore single firing and to that end have all my test
> "tiles" (OK, shot glasses) lined up and ready to glaze.
> Here's the question...
> Is there a recommended way to wax the bottoms?
> I typically use an electric skillet with melted wax to coat the foot of
> my bisqueware, but my instinct tells me that setting bone dry greenware
> into a vat of liquid paraffin will #1 disintegrate the greenware and #2
> create problems with the glaze and body drying properly.
> Hmmmm.
>
> I've not been able to find too much on the 'net about the process.
> All tips are greatly appreciated!
>
> --
> Cathi Newlin, Angels Camp, Ca
> cathi@box49.com
> box49@caltel.com
> cathi@SquarePegArts.com
> -------------------------------
> California Boxers in Need:
> http://CaliforniaBoxer.org
>

Bonnie Staffel on sun 24 jan 10


My advice is to just try a single piece and learn from it.


>I'm wanting to explore single firing and to that end have all my test
"tiles" (OK, shot glasses) lined up and ready to glaze. Here's the
question... Is there a recommended way to wax the bottoms? I typically =3D
use
an electric skillet with melted wax to coat the foot of my bisqueware, =3D
but
my instinct tells me that setting bone dry greenware into a vat of =3D
liquid
paraffin will #1 disintegrate the greenware and #2 create problems with =3D
the
glaze and body drying properly. Hmmmm.>

Bonnie Staffel


http://webpages.charter.net/bstaffel/
http://vasefinder.com/bstaffelgallery1.html
DVD=3DA0 Throwing with Coils and Slabs
DVD=3DA0 Introduction to Wheel Work
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