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: stainless steel and ceramic

updated sat 5 apr 03

 

iandol on wed 2 apr 03


Dear Friends,
There are times I wonder if we learn anything useful through this list. =
If people had asked a question about the relationship between a glaze =
and a clay we would have been told double sharp time quick left right =
left right to consider the Coef of Exp and get it right.
Same with this problem. On the evidence before me I would say it is a =
No-No.
Clays have a Coef of Exp in the range 6 times 10 to the minus six, =
Stainless steels in the range of 16 times 10 to the minus six for 18 =
Chrome 8 Nickel.
So heating the steel will expand more by a factor of about two and half. =
I would imagine the Stress generated by this would disrupt the clay =
before it had even started to mature. But I could be wrong.
Best regards,
Ivor.

pdp1@EARTHLINK.NET on thu 3 apr 03


Dear Ivor,

Do you think the Clay could shrink away from the Stainless
Armature when drying...to allow this differential expansion
some lee-way for itself once matters are heating up?

Just a thought...

Phil
el of vee


----- Original Message -----
From: "iandol"
To:
Sent: Tuesday, April 01, 2003 10:09 PM
Subject: : Stainless steel and ceramic


Dear Friends,
There are times I wonder if we learn anything useful through
this list. If people had asked a question about the
relationship between a glaze and a clay we would have been
told double sharp time quick left right left right to
consider the Coef of Exp and get it right.
Same with this problem. On the evidence before me I would
say it is a No-No.
Clays have a Coef of Exp in the range 6 times 10 to the
minus six, Stainless steels in the range of 16 times 10 to
the minus six for 18 Chrome 8 Nickel.
So heating the steel will expand more by a factor of about
two and half. I would imagine the Stress generated by this
would disrupt the clay before it had even started to mature.
But I could be wrong.
Best regards,
Ivor.

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John Britt on thu 3 apr 03


Ivor,

I have used stainless steel welding rods to give support to sculptures
many times.

Theoritically it is impossible, but practically it works. There are
probably ruptures around the rod in the low shrinkage body, but that does
not cause it to fall apart. If I use larger rod, I wiggle the rod and
that allows clay "space" to shrink around the rod and then presumably
assists in the differences in the exp/cont. of the steel and the clay.

John Britt