Cara Moczygemba on sat 6 jun 98
I have a story and a question for all the kiln experimenters out there:
I have, for years, added metal pieces into some of my sculptures, usually
steel, since that works best (it doesn't melt out). This past week I made and
bisqued a piece with 6 - four inch nails sticking out, and when i opened the
kiln I was very surprised.
The nails seemed to have grown skins, and not just a loose crust that flaked
off, but these looked like underwater creatures or plants, bumpy and scaly and
wrinkled skins with white crusty tendrils growing out from them, one had a
single tendril that was three or four inches long, looking like a bit of ivy
looking for something to grab onto. Everything had a dusting of white powder,
and the tendrils, though hard, were brittle and came right off. I took
pictures, and then scraped them off and disposed of all the growth.
I think the nails must have been zinc coated (they looked plain, but ...) and
want to know if anyone else has ever had that sort of experience, or can
explain it, and if it is hazardous, to me, to the kiln ... whatever.
Cara
in New Orleans
way too hot, definitely no summer workshops here.
David Hendley on sun 7 jun 98
I also think your nails must have been zinc coated (galvanized) - the white
powder, the scaly surface indicate that.
When cutting or welding galvanized steel, the fumes emmited are
considered a health hazard, so I would treat the fumes from your
kiln as hazardous also.
David Hendley
Maydelle, Texas
At 10:08 AM 6/6/98 EDT, you wrote:
>----------------------------Original message----------------------------
>I have a story and a question for all the kiln experimenters out there:
>
>I have, for years, added metal pieces into some of my sculptures, usually
>steel, since that works best (it doesn't melt out). This past week I made
and
>bisqued a piece with 6 - four inch nails sticking out, and when i opened the
>kiln I was very surprised.
>
>The nails seemed to have grown skins, and not just a loose crust that flaked
>off, but these looked like underwater creatures or plants, bumpy and scaly
and
>wrinkled skins with white crusty tendrils growing out from them, one had a
>single tendril that was three or four inches long, looking like a bit of ivy
>looking for something to grab onto. Everything had a dusting of white
powder,
>and the tendrils, though hard, were brittle and came right off. I took
>pictures, and then scraped them off and disposed of all the growth.
>
>I think the nails must have been zinc coated (they looked plain, but ...) and
>want to know if anyone else has ever had that sort of experience, or can
>explain it, and if it is hazardous, to me, to the kiln ... whatever.
>
>Cara
>in New Orleans
>way too hot, definitely no summer workshops here.
>
Lorca Beebe on sun 7 jun 98
Cara:
If you liked that, try pennies, these produce spiral kind of fingers at cone
04, its probably the zinc and other alloys, some of the alchemists on the list
probably have a more "vulcan" explanation...
Lorca
Vince Pitelka on sun 7 jun 98
>looking for something to grab onto. Everything had a dusting of white powder,
>and the tendrils, though hard, were brittle and came right off. I took
>pictures, and then scraped them off and disposed of all the growth.
>I think the nails must have been zinc coated (they looked plain, but ...) and
>want to know if anyone else has ever had that sort of experience, or can
>explain it, and if it is hazardous, to me, to the kiln ... whatever.
Cara -
Yes, the nails must have been galvanized (zinc coated). I also have often
used metal parts in my work, fired with the work to low-fire temperatures.
Usually I use black-iron pipe, but one time I included some galvanized pipe,
and the results were just as you described - a white powdery coating all
over the pipe, and alien tendrils of powdery substance growing out of the
surface. These tendrils were hollow, and disintegrated as soon as the piece
was moved. Apparently they were formed of volatizing metalic zinc,
redepositing as oxide as it leaves the surface of the pipe. That's my
guess. I have tried to describe the effect to many people, and a good
number of them remained skeptical. Nice to know there is someone out there
who has also experienced the same thing.
This phenomenon is very interesting to see, but I do not recommend that
anyone try it. Zinc fumes are very toxic. Way way back, when I worked as
an equipment mechanic, there were a number of times when I welded galvanized
pipe without proper protection, and got pretty sick as a result. This was
25 years ago, and I shudder to think how careless we were about some safety
issues back then.
- Vince
Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Milton Markey on sun 7 jun 98
Hi Cara!
Like yourself, I often add metallic bits and pieces to my sculptures and
masks. My best source is the local metal recycling yard--I pick up metal
fragments which dropped to the ground. I've used nails, too, and came up with
a result simular to the one you describe. Like yourself, I'm not a metal
expert, but through my experience and intuition, I'll share my two cents
worth.
I think the "skin" you described comes from a variety of atmospheric and
chemical reactions. Not only is the nail's metal and coating a factor, but the
attributes of the kiln and its contents probably contribute to the weird look,
too. You don't mention the cone you fired your work to, nor the atmosphere
(oxy or reduction), or the kind of kiln. All these variables contribute to how
metal and clay will react and bond, when they are fired together.
My metal of choice, when I add fragments to my work, is copper wire. It melts
at a low temperature, so protect your kiln shelves! I usually fire my
sculptures to cone 6 oxy. I clean short lengths of scrap electrical wire by
removing any plastic or strings which accompany the wire. Then I cut the wire
into little bits and "sprinkle" the wire bits over a sculpture. Sometimes I do
this on an unglazed surface, while other times I sprinkle wire over a glazed
piece. Depending on the clay body used, the results are specular black
"spots" where the wire once was.
One of my collectors calls the effect "subtle fireworks."
One thing to note: most of my sculptures are made from flat slabs and concave
surfaces. To coat vertical surfaces or rounded forms, try adding the copper
bits into your favorite glaze. Caveat: copper wire may act as a flux. By
itself, it can flow freely at cone 6 and above. Also, be careful when loading
a piece with wire or any other metal into an electric kiln. Any bare metal
that gets knocked onto the elements may cause an unexpected short circuit, or
may otherwise damage the kiln.
I encourage you to keep experimenting!
Milton (MiltonsLin@AOL.COM) of Yucca Valley. The indigo bushes are blooming.
There's one bush out by my mailbox which is lush with deep blue blossoms. The
contrast of this bush to the neighboring "blue bar" creosote, with its bright
yellow flowers, makes retrieving the mail a pleasant task.
Edouard Bastarache on mon 8 jun 98
Hi
fresh zinc oxide made from welding and cutting galvanized steel causes
"Metal fume fever",
a mild medical condition lasting about 24 hours and mimicking the beginning
of a cold.
The treatment is symptomatic and recovery is rapid,there is no long term
effects and is frequently
encountered among welders.
If after 24- 36 hours you are still symptomatic it means you have a cold
which may last more than a week.
Acetaminophen( Tylenol) or aspirin(if you are not allergic) are the drugs
of choice.
Later
Edourad Bastarache M.D.( Occupational & environmental medicine)
Tracy
Quebec
Canada
----------
> De : David Hendley
> A : Multiple recipients of list CLAYART
> Objet : Re: weird stuff from the kiln gods?
> Date : 7 juin, 1998 11:13
>
> ----------------------------Original message----------------------------
> I also think your nails must have been zinc coated (galvanized) - the
white
> powder, the scaly surface indicate that.
>
> When cutting or welding galvanized steel, the fumes emmited are
> considered a health hazard, so I would treat the fumes from your
> kiln as hazardous also.
>
> David Hendley
> Maydelle, Texas
>
>
>
> At 10:08 AM 6/6/98 EDT, you wrote:
> >----------------------------Original message----------------------------
> >I have a story and a question for all the kiln experimenters out there:
> >
> >I have, for years, added metal pieces into some of my sculptures,
usually
> >steel, since that works best (it doesn't melt out). This past week I
made
> and
> >bisqued a piece with 6 - four inch nails sticking out, and when i opened
the
> >kiln I was very surprised.
> >
> >The nails seemed to have grown skins, and not just a loose crust that
flaked
> >off, but these looked like underwater creatures or plants, bumpy and
scaly
> and
> >wrinkled skins with white crusty tendrils growing out from them, one had
a
> >single tendril that was three or four inches long, looking like a bit of
ivy
> >looking for something to grab onto. Everything had a dusting of white
> powder,
> >and the tendrils, though hard, were brittle and came right off. I took
> >pictures, and then scraped them off and disposed of all the growth.
> >
> >I think the nails must have been zinc coated (they looked plain, but
...) and
> >want to know if anyone else has ever had that sort of experience, or can
> >explain it, and if it is hazardous, to me, to the kiln ... whatever.
> >
> >Cara
> >in New Orleans
> >way too hot, definitely no summer workshops here.
> >
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