<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; = charset=us-ascii"> <META content="MSHTML 6.00.2900.2769" name=GENERATOR></HEAD> <BODY> <DIV dir=ltr align=left><FONT face="Comic Sans MS" color=#000080></FONT> </DIV><BR> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000080 2px = solid; MARGIN-RIGHT: 0px"> <DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left> <HR tabIndex=-1> <FONT face=Tahoma size=2><B>From:</B> pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] <B>On Behalf Of </B>Andrew and = Rebeca Anderson<BR><B>Sent:</B> December 05, 2005 10:13 AM<BR><B>To:</B> Pianotech<BR><B>Subject:</B> Re: Petrifying process of wood <BR></FONT><BR></DIV> <DIV></DIV> <DIV>Petrification involves mineralization, usually water-born.  = Usually underground where aerobic bacteria can't thrive.<BR><BR>A failed = sound-board has more to do with structural compression damage to the wood = fibers.  Ie ten year old Chinese pianos with coastal spruce where the fat grain = has dried out and the board collapsed.  The wood has lost its "stiffness" = and absorbs vibrations much more than it did when new.  To a lesser = degree this happens to old boards.  Sometimes re-ribbing can revive a board.  Shimming cracks that divide a board is another = time-tested method.<BR><SPAN class=687113618-05122005><FONT face="Comic Sans = MS" color=#000080></FONT></SPAN></DIV></BLOCKQUOTE> <DIV><SPAN class=687113618-05122005> </SPAN></DIV> <DIV><SPAN class=687113618-05122005><FONT face="Comic Sans MS" = color=#000080>... that does not work to either stiffen the original soundboard or to = restore crown.</FONT></SPAN></DIV> <DIV><SPAN class=687113618-05122005><FONT face="Comic Sans MS" color=#000080></FONT></SPAN> </DIV> <DIV><SPAN class=687113618-05122005><FONT face="Comic Sans MS" color=#000080>Del</FONT></SPAN></DIV> <DIV><SPAN class=687113618-05122005><FONT face="Comic Sans MS" color=#000080></FONT></SPAN> </DIV> <DIV><SPAN class=687113618-05122005><FONT face="Comic Sans MS" color=#000080></FONT></SPAN> </DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000080 2px = solid; MARGIN-RIGHT: 0px"> <DIV><SPAN class=687113618-05122005><FONT face="Comic Sans MS" color=#000080></FONT></SPAN> </DIV> <DIV><SPAN class=687113618-05122005> </SPAN></DIV></BLOCKQUOTE></BODY></HTML>=