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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: =
black"><B>From:</B>
<A title=mathstar@salemnet.com =
href="mailto:mathstar@salemnet.com">Alan R.
Barnard</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A =
title=pianotech@ptg.org
href="mailto:pianotech@ptg.org">pianotech@ptg.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> August 27, 2002 4:57 =
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Foundry =
Castings</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Cast iron IS brittle but it will not =
deform nor
compress under stress and tension the way steel, aluminum, and other =
metals
do. </FONT></DIV></BLOCKQUOTE>
<DIV dir=ltr><FONT face=Arial size=2>Yes, it does. It bends rather =
easily up to
a point. Then it breaks.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
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<DIV><FONT face=Arial size=2>Nor does it expand and contract with =
changing
temperatures as much as other metals. The key point is that it holds =
its shape
and, most important, the critical string length dimensions.
</FONT></DIV></BLOCKQUOTE>
<DIV dir=ltr><FONT face=Arial size=2>The difference in thermal =
expansion and
contraction between gray iron and the steel used to make piano wire is
nominal.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
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<DIV><FONT face=Arial size=2>I'm guessing that a lot of the metal =
in the
casting is just to make the plate "beefier" so it doesn't break so =
easily.
</FONT></DIV></BLOCKQUOTE>
<DIV dir=ltr><FONT face=Arial size=2>That, and it's just easier. =
You don't have
to 'design' it--you just throw extra iron at it. As well, piano plate =
foundries
have not been noted for their consistency in casting.</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr><FONT face=Arial size=2>Del</FONT></DIV>
<DIV dir=ltr><FONT face=Arial size=2></FONT> </DIV>
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