<!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 6.00.2900.2668" name=GENERATOR></HEAD> <BODY id=role_body style="FONT-SIZE: 10pt; COLOR: #000000; = FONT-FAMILY: Arial" bottomMargin=7 leftMargin=7 topMargin=7 rightMargin=7> <DIV dir=ltr align=left><FONT face="Comic Sans MS" color=#000080 = size=3></FONT> </DIV><BR> <BLOCKQUOTE dir=ltr 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>Erwinspiano@aol.com<BR><B>Sent:</B> June 24, 2005 6:51 = AM<BR><B>To:</B> pianotech@ptg.org<BR><B>Subject:</B> Re: Rib Crowned Hamburgs ?<BR></FONT><BR></DIV> <DIV></DIV><FONT id=role_document face=Arial color=#000000 = size=2> <DIV> <DIV>    I suppose it's possible but I meant = the old boards I've seen typically are a bit thicker on top. On the other hand = as far as a general board thickness parameter between even the same models = does not exist.</DIV> <DIV>     Dale<SPAN = class=078490215-24062005><FONT face="Comic Sans MS" color=#000080 = size=3> </FONT></SPAN></DIV> <DIV><SPAN = class=078490215-24062005></SPAN> </DIV></DIV></BLOCKQUOTE> <DIV dir=ltr><SPAN class=078490215-24062005><FONT face="Comic Sans = MS" color=#000080 size=3>Ah, yes. Well, they were thicker back before = the "Diaphragmatic Soundboard" was invented back in the early 1930s. We've = replaced enough boards in pianos made through the 1980s and 1990s to see some of = the results of boards this thin combined with compression crowning.</FONT></SPAN></DIV> <DIV dir=ltr><SPAN class=078490215-24062005></SPAN> </DIV> <DIV dir=ltr><SPAN class=078490215-24062005><FONT face="Comic Sans = MS" color=#000080 size=3>Del</FONT></SPAN></DIV></FONT></BODY></HTML>