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<DIV><STRONG><FONT face=Arial>Hi Terry,</FONT></STRONG></DIV>
<DIV><STRONG><FONT face=Arial>Very interesting.</FONT></STRONG></DIV>
<DIV><STRONG><FONT face=Arial>I have to hand it to you, you really do get into
things.</FONT></STRONG></DIV>
<DIV><STRONG><FONT face=Arial>Best regards,</FONT></STRONG></DIV>
<DIV> <SPAN id=__#Ath#SignaturePos__></SPAN> </DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=mfarrel2@tampabay.rr.com
href="mailto:mfarrel2@tampabay.rr.com">Farrell</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> Saturday, March 29, 2003 11:31
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Soundboard Torture</DIV>
<DIV><BR></DIV>
<DIV>This is what your soundboard wants to do when exposed to high humidity.
Below is a photo of my mechanical moisture content (MC) meter. The wooden
part is a 4-foot long by 4-inch wide chunk of soundboard panel. The panel is
about 3/8 inch thick and has two ribs on the back (bottom in this photo) that
are about 3/8-inch thick by 3/4-inch wide. The ribs were glued on when the
panel and ribs were flat and at about 4% or 5% MC. The meter has
been in an 85% to 89% RH environment for three days now. It seems to have
nearly stabilized. I did not measure the crown, but as you can see it is
somewhere around 6 to 8 inches.</DIV>
<DIV><STRONG><FONT face=Arial>Picture removed for reply</FONT></STRONG></DIV>
<DIV>Soundboard panels in pianos exposed to high humidity are trying to do
what you see above. The stiff ribs and string downbearing pressure keep it
from actually developing 8 inches of crown. And instead of being able to
expand and produce this kind of crown, the soundboard simply crushes. No
wonder soundboard panels develop pressure ridges and then cracks when they dry
back down! The scale on the left goes from about 5.5% MC to about 8.5% MC. The
panel should be in the range of 18% MC in this photo.</DIV>
<DIV> </DIV>
<DIV>Fun stuff!</DIV>
<DIV> </DIV>
<DIV>Terry Farrell</DIV></BLOCKQUOTE></BODY></HTML>