gina mars on sun 11 dec 11
Hi All again,
This morning an inquisitive 10 year old brought a cup of beach glass
to class. He asked me to fire it in the middle of his bowl to get some =3D
interesting effects.
Before I do it, I have some questions. Is this safe to do at cone 6? =3D
Could the bowl split=3D20
and the glass run everywhere? It's mostly blue glass chunks he found on =3D
the beach.
At a gallery near my home, I see a lady sells large bowls and sushi =3D
platters with at least
1 inch or so of melted glass in the middle. it has lots of depth and =3D
cracks. How can this be food safe?
The gallery owner mentioned the pots were fired to high temp and then =3D
fired again
with the glass in the middle. Still I see all these cracks and can't =3D
help but think it;s not
a good idea to put food in it..
Thank You, Happy Holidays!
Gina Mars
www.marspottery.net
Huntington Station, NY, where it's now getting cold.
Vince Pitelka on sun 11 dec 11
Gina Mars wrote:
"This morning an inquisitive 10 year old brought a cup of beach glass to
class. He asked me to fire it in the middle of his bowl to get some
interesting effects. Before I do it, I have some questions. Is this safe to
do at cone 6? Could the bowl split and the glass run everywhere? It's mostl=
y
blue glass chunks he found on the beach. At a gallery near my home, I see a
lady sells large bowls and sushi platters with at least 1 inch or so of
melted glass in the middle. it has lots of depth and cracks. How can this b=
e
food safe? The gallery owner mentioned the pots were fired to high temp an=
d
then fired again with the glass in the middle. Still I see all these cracks
and can't help but think it;s not a good idea to put food in it."
Hi Gina -
Mel's post pretty much said it all, especially at the end - "There are
enough non food ideas to let you make glass bottomed pots for your
lifetime." The people who sell functional bowls and plates with a thick
accumulation of crackled melted glass in the food-contact areas are asking
for a lawsuit. Everyone on this list knows that I speak out against
over-the-top toxic/safety alarms, but in this case the risk is real. You
never know when expansion and contraction are going to cause razor-sharp
chunks of glass to come loose in someone's food, causing a broken tooth, cu=
t
mouth or tongue, or worse. It is not worth the risk on food-contact
surfaces. Lots of people think the effect is pretty and obviously it sells
well, but I would confine it to non-food items. Don't listen to the people
who say this is not a risk, because in their case, they simply have not yet
experienced the crackled glass coming loose unexpectedly.
- Vince
Vince Pitelka
Appalachian Center for Craft
Tennessee Tech University
vpitelka@dtccom.net
http://iweb.tntech.edu/wpitelka/
Lee on sun 11 dec 11
On Sun, Dec 11, 2011 at 7:43 AM, gina mars wrote:
> Hi All again,
> This morning an inquisitive 10 year old brought a cup of beach glass
> to class. He asked me to fire it in the middle of his bowl to get some
> interesting effects.
> Before I do it, I have some questions. Is this safe to do at cone 6?
A friend who has a pottery business in my nieghborhood, Kerry Brooks, (she
has reduction fired work for me when NCC's scheduler was booked, or like
when I needed pots for my workshop in Little Rock), specializes in this
technique. When I was there a couple weeks ago, it was like Santa's
Workshop, within my vision were a dozen people grinding bottoms of tiles.
She makes a circle in the tile where the glass pools. These tiles
dominate here sales (Like the Redart guy who ended up only making pie
plates because of demand, but she makes all sorts of functional bowls.
Please look below. The pooled glass looks nice:
http://www.dock6pottery.com/dock6_gallery(pottery_glass).php
--
Lee Love in Minneapolis
http://mingeisota.blogspot.com/
"Ta tIr na n-=3DF3g ar chul an tI=3D97tIr dlainn trina ch=3DE9ile"=3D97tha=
t is, "T=3D
he land
of eternal youth is behind the house, a beautiful land fluent within
itself." -- John O'Donohue
William & Susan Schran User on sun 11 dec 11
On 12/11/11 10:36 AM, "Vince Pitelka" wrote:
> The people who sell functional bowls and plates with a thick
> accumulation of crackled melted glass in the food-contact areas are askin=
g
> for a lawsuit. Everyone on this list knows that I speak out against
> over-the-top toxic/safety alarms, but in this case the risk is real. You
> never know when expansion and contraction are going to cause razor-sharp
> chunks of glass to come loose in someone's food, causing a broken tooth, =
cut
> mouth or tongue, or worse. It is not worth the risk on food-contact
> surfaces. Lots of people think the effect is pretty and obviously it sel=
ls
> well, but I would confine it to non-food items. Don't listen to the peop=
le
> who say this is not a risk, because in their case, they simply have not y=
et
> experienced the crackled glass coming loose unexpectedly.
I agree with Vince on this one.
Melted glass in the bottom of bowls/plates creates an attractive visual
effect, but without knowing the chemistry of the glass, how it fits or does
not fit the clay/glaze surface and more importantly, how the customer might
use the piece enters into the realm of uncertainty when we discuss surface
stability or safety.
I would suggest anyone selling this type of ware to apply a sticker to the
bottom of the pot reading: "for decorative purposes only".
FYI - I've had a student explore this process in raku to great effect!
She would create bowls with very intricate undersea world like scenarios,
squeezing out little clay forms using a pastry bag/tip as one might with
slip trailing, then for the glaze firing, fill the bowl with broken glass o=
r
glass circles from a crafts store. The molten glass was often more than an
inch thick!
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
jcu on sun 11 dec 11
Lately, I have been finding some really beautiful pottery pieces
at Goodwill. You never know what is going to turn up there, or in=3D20
a garage sale. Stickers eventually fall off. So I've often thought that=3D2=
0=3D
a stamp pushed right into the bottom of a leatherhard pot (with the=3D20
necessary description) is better than a sticker. Not sure what the=3D20
best choice of words is, but branding the pot as "not food safe"=3D20
is a fair warning. Does anyone do this?
joan
On 2011-12-11, at 12:09 PM, William & Susan Schran User wrote:
> On 12/11/11 10:36 AM, "Vince Pitelka" wrote:
>=3D20
>> The people who sell functional bowls and plates with a thick
>> accumulation of crackled melted glass in the food-contact areas are =3D
asking
>> for a lawsuit. Everyone on this list knows that I speak out against
>> over-the-top toxic/safety alarms, but in this case the risk is real. =
=3D
You
>> never know when expansion and contraction are going to cause =3D
razor-sharp
>> chunks of glass to come loose in someone's food, causing a broken =3D
tooth, cut
>> mouth or tongue, or worse. It is not worth the risk on food-contact
>> surfaces. Lots of people think the effect is pretty and obviously it =
=3D
sells
>> well, but I would confine it to non-food items. Don't listen to the =3D
people
>> who say this is not a risk, because in their case, they simply have =3D
not yet
>> experienced the crackled glass coming loose unexpectedly.
>=3D20
> I agree with Vince on this one.
> Melted glass in the bottom of bowls/plates creates an attractive =3D
visual
> effect, but without knowing the chemistry of the glass, how it fits or =
=3D
does
> not fit the clay/glaze surface and more importantly, how the customer =3D
might
> use the piece enters into the realm of uncertainty when we discuss =3D
surface
> stability or safety.
> I would suggest anyone selling this type of ware to apply a sticker to =
=3D
the
> bottom of the pot reading: "for decorative purposes only".
>=3D20
> FYI - I've had a student explore this process in raku to great effect!
> She would create bowls with very intricate undersea world like =3D
scenarios,
> squeezing out little clay forms using a pastry bag/tip as one might =3D
with
> slip trailing, then for the glaze firing, fill the bowl with broken =3D
glass or
> glass circles from a crafts store. The molten glass was often more =3D
than an
> inch thick!
>=3D20
> Bill
> --
> William "Bill" Schran
> wschran@cox.net
> wschran@nvcc.edu
> http://www.creativecreekartisans.com
Gayle Bair on sun 11 dec 11
Not making it a functional piece is the most safe and ethical rule but some
will not listen to advice from our gurus. A sticker will wash off but
incising " Not food safe" on the bottom of the piece will not wash off.
IMHO it's very pretty but not worth the risk.
Gayle
On Sun, Dec 11, 2011 at 9:09 AM, William & Susan Schran User <
wschran@cox.net> wrote:
I agree with Vince on this one.
> Melted glass in the bottom of bowls/plates creates an attractive visual
> effect, but without knowing the chemistry of the glass, how it fits or do=
es
> not fit the clay/glaze surface and more importantly, how the customer mig=
ht
> use the piece enters into the realm of uncertainty when we discuss surfac=
e
> stability or safety.
> I would suggest anyone selling this type of ware to apply a sticker to th=
e
> bottom of the pot reading: "for decorative purposes only".
>
> FYI - I've had a student explore this process in raku to great effect!
> She would create bowls with very intricate undersea world like scenarios,
> squeezing out little clay forms using a pastry bag/tip as one might with
> slip trailing, then for the glaze firing, fill the bowl with broken glass
> or
> glass circles from a crafts store. The molten glass was often more than a=
n
> inch thick!
>
> Bill
> --
> William "Bill" Schran
> wschran@cox.net
> wschran@nvcc.edu
> http://www.creativecreekartisans.com
>
Steve Mills on mon 12 dec 11
Glass used as decoration on the outside of pots is fine, earthenware to hig=
h=3D
stoneware. Look at the work of many traditional NC Potters and current one=
s=3D
like Mark Hewitt.=3D20
NOT however recommended inside them if they are for food or drink use, most=
l=3D
y because of the crazing.=3D20
In my experience lead based glass only works at low earthenware, and the sa=
m=3D
e rules apply in full, together with the possibility of Lead release added =
i=3D
n as well.=3D20
Steve M
Sent from my iPod
On 11 Dec 2011, at 13:43, gina mars wrote:
> Hi All again,
> This morning an inquisitive 10 year old brought a cup of beach glass
> to class. He asked me to fire it in the middle of his bowl to get some in=
t=3D
eresting effects.
> Before I do it, I have some questions. Is this safe to do at cone 6? Coul=
d=3D
the bowl split=3D20
> and the glass run everywhere? It's mostly blue glass chunks he found on t=
h=3D
e beach.
> At a gallery near my home, I see a lady sells large bowls and sushi platt=
e=3D
rs with at least
> 1 inch or so of melted glass in the middle. it has lots of depth and crac=
k=3D
s. How can this be food safe?
> The gallery owner mentioned the pots were fired to high temp and then fi=
r=3D
ed again
> with the glass in the middle. Still I see all these cracks and can't help=
b=3D
ut think it;s not
> a good idea to put food in it..
> Thank You, Happy Holidays!
> Gina Mars
> www.marspottery.net
> Huntington Station, NY, where it's now getting cold.
marci Boskie's Mama =3D^..^=3D on mon 12 dec 11
Vince wrote:
>The people who sell functional bowls and plates with a thick
>accumulation of crackled melted glass in the food-contact areas are asking
>for a lawsuit. Everyone on this list knows that I speak out against
>over-the-top toxic/safety alarms, but in this case the risk is real.
(snip )
> Don't listen to the people
>who say this is not a risk, because in their case, they simply have not ye=
t
>experienced the crackled glass coming loose unexpectedly.
>- Vince
------------
I'm with you on this one , Vince. Annealing the glass by firing
down and holding at certain temps ( there is a lot of info on the
net about this on glass fusing and glass bead sites) will help
stabilize things... but stresses in glass can wreck havoc months or
years later... I would be very nervous to use these with food...
marci the chinapainter ..
Arnold Howard on mon 12 dec 11
On 12/11/2011 11:09 AM, William & Susan Schran User wrote:
> I agree with Vince on this one.
> Melted glass in the bottom of bowls/plates creates an attractive visual
> effect, but without knowing the chemistry of the glass, how it fits or do=
es
> not fit the clay/glaze surface and more importantly, how the customer mig=
ht
> use the piece enters into the realm of uncertainty
This is prudent advice. Glass that has been fused to an incompatible
surface can crack even months after it has come out of the kiln.
Sincerely,
Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com
Rimas VisGirda on tue 13 dec 11
Now I need to throw out my lead crystal glassware along with the (old) Fies=
=3D
ta! But, but, but where to throw it? If I put it in a landfill, it will lea=
=3D
ch out and contaminate our drinking water and rivers and oceans... -damn yo=
=3D
u lead! You seduce us with your beauty and condemn us to unrequited love...=
=3D
-Rimas=3D0A=3D0ADate:=3DA0 =3DA0 Mon, 12 Dec 2011 00:48:47 +0000=3D0AFrom:=
=3DA0 =3DA0 St=3D
eve Mills =3D0ASubject: Re: Glass in the bow=
l =3D
question=3D0A=3D0AGlass used as decoration on the outside of pots is fine, =
eart=3D
henware to high=3D3D=3D0Astoneware. Look at the work of many traditional NC=
Pot=3D
ters and current ones=3D3D=3D0Alike Mark Hewitt.=3D3D20=3D0ANOT however rec=
ommended=3D
inside them if they are for food or drink use, mostl=3D3D=3D0Ay because of=
the=3D
crazing.=3D3D20=3D0AIn my experience lead based glass only works at low ea=
rthe=3D
nware, and the sam=3D3D=3D0Ae rules apply in full, together with the possib=
ilit=3D
y of Lead release added i=3D3D=3D0An as well.=3D3D20=3D0A=3D0ASteve M=3D0A
gina mars on tue 13 dec 11
I had to add to this. After the responses, I visited the store with the =3D
glass in the pots ect. I asked the nice lady at the desk about them. She =
=3D
said they were not food safe but didn't post a sign and explained to me =3D
that just recently she got a really bad cut. She was wrapping a bowl and =
=3D
her hand somehow ran across the glass on the bottom. Blood everywhere! =3D
even on the customer. Yikes!
Gina Mars
www.marspottery.net
off to make those holiday cookies. I'll be on the treadmill as they cook =
=3D
every 12 minutes. LOL
On Dec 13, 2011, at 12:21 PM, Rimas VisGirda wrote:
> Now I need to throw out my lead crystal glassware along with the (old) =
=3D
Fiesta! But, but, but where to throw it? If I put it in a landfill, it =3D
will leach out and contaminate our drinking water and rivers and =3D
oceans... -damn you lead! You seduce us with your beauty and condemn us =3D
to unrequited love... -Rimas
>=3D20
> Date: Mon, 12 Dec 2011 00:48:47 +0000
> From: Steve Mills
> Subject: Re: Glass in the bowl question
>=3D20
> Glass used as decoration on the outside of pots is fine, earthenware =3D
to high=3D3D
> stoneware. Look at the work of many traditional NC Potters and current =
=3D
ones=3D3D
> like Mark Hewitt.=3D3D20
> NOT however recommended inside them if they are for food or drink use, =
=3D
mostl=3D3D
> y because of the crazing.=3D3D20
> In my experience lead based glass only works at low earthenware, and =3D
the sam=3D3D
> e rules apply in full, together with the possibility of Lead release =3D
added i=3D3D
> n as well.=3D3D20
>=3D20
> Steve M
>=3D20
Pam Cresswell on tue 13 dec 11
I make and sell little incense burners with glass melted in the bottom. It
makes a nice flat and level spot for a cone of incense to sit on, and as
mentioned,
the crackled glass is very pretty. I too discovered that it works better to
glaze the pot as usual first, then put glass shards on top of the glaze. I
also drizzle glaze
into the pile of shards, it seems to help it melt better at ^6. Without
glaze, I have had glass melt but not run into the depression. It sat up lik=
e
a lump.
Pam
-----Original Message-----
From: Steve Mills
Sent: Tuesday, December 13, 2011 6:27 PM
To: Clayart@LSV.CERAMICS.ORG
Subject: Re: Glass in the bowl question
As a matter of interest. Many years ago we found that a coat of good white
gloss glaze UNDERNEATH the glass stabilised the whole technique, by acting
as a "glue", holding everything together.
It also had the advantage of enlivening the colour of the glass overlay.
Never had a problem of any sort following that rule.
These pieces were NEVER for food use.
Steve M
Sent from my iPod
Steve Mills on wed 14 dec 11
As a matter of interest. Many years ago we found that a coat of good white =
g=3D
loss glaze UNDERNEATH the glass stabilised the whole technique, by acting a=
s=3D
a "glue", holding everything together.=3D20
It also had the advantage of enlivening the colour of the glass overlay.=3D=
20
Never had a problem of any sort following that rule.=3D20
These pieces were NEVER for food use.=3D20
Steve M
Sent from my iPod
On 12 Dec 2011, at 23:41, "marci Boskie's Mama =3D3D^..^=3D3D" COM> w=3D
rote:
> Vince wrote:
>> The people who sell functional bowls and plates with a thick
>> accumulation of crackled melted glass in the food-contact areas are aski=
n=3D
g
>> for a lawsuit. Everyone on this list knows that I speak out against
>> over-the-top toxic/safety alarms, but in this case the risk is real.
>=3D20
> (snip )
>> Don't listen to the people
>> who say this is not a risk, because in their case, they simply have not =
y=3D
et
>> experienced the crackled glass coming loose unexpectedly.
>> - Vince
> ------------
> I'm with you on this one , Vince. Annealing the glass by firing
> down and holding at certain temps ( there is a lot of info on the
> net about this on glass fusing and glass bead sites) will help
> stabilize things... but stresses in glass can wreck havoc months or
> years later... I would be very nervous to use these with food...
>=3D20
> marci the chinapainter ..
| |
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