<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; = charset=iso-8859-1"> <META content="MSHTML 5.50.4134.600" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=#ffffff> <DIV><FONT color=#000080></FONT> </DIV> <BLOCKQUOTE style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; = BORDER-LEFT: #000080 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=Erwinspiano@AOL.COM href="mailto:Erwinspiano@AOL.COM">Erwinspiano@AOL.COM</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> July 11, 2002 6:35 = AM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: rib radius</DIV> <DIV><BR></DIV> <DIV><FONT face=arial,helvetica><FONT lang=0 face="Times New = Roman" size=3 FAMILY="SERIF">In a message dated 7/11/2002 4:31:37 AM Pacific = Daylight Time, <A = href="mailto:mfarrel2@tampabay.rr.com">mfarrel2@tampabay.rr.com</A> writes:<BR><BR>        Dittos = Terry. <BR>    I Know of no on using less crown in the treble. = At least many are using 60ft. thru out and many of us increasing radius into  the treble. I think the confusion is that a 60 ft. curve on = a 40 inch rib appears to have proportionally more crown (7-8 mm) than a 15 = inch rib with a 25 ft. curve ( 1.5mm) when observed visually. <BR>>>>>>Dale Erwin>>>>>>>></FONT></FONT></DIV></BLOCKQUOTE> <DIV><FONT face="Times New Roman"></FONT> </DIV><FONT face=arial,helvetica><FONT lang=0 face="Times New Roman" size=3 FAMILY="SERIF"></FONT></FONT> <DIV><FONT face="Times New Roman">Dale & Terry,</FONT></DIV> <DIV><FONT face="Times New Roman"></FONT> </DIV> <DIV><FONT face="Times New Roman">Let's define our terms here. When = talking about increasing or decreasing crown we're generally referring to the = amount of visible curvature in the system -- a particular rib or the whole board. = So an increase in crown means the system has more visible curve and a decrease = in crown has less. It's the radius of the curve that is changing. Now, </FONT><FONT face="Times New Roman">if we're talking about = radius then a rib cut to a 40' radius has more crown than does a rib cut to a = numerically larger 60' radius. Regardless of length.</FONT></DIV> <DIV><FONT face="Times New Roman"></FONT> </DIV> <DIV><FONT face="Times New Roman">We use ribs of smaller radius = (larger crown) in the treble and ribs of larger radius (smaller crown) in the bass.</FONT></DIV> <DIV><FONT face="Times New Roman"></FONT> </DIV> <DIV><FONT face="Times New Roman">At least I think that's what Terry = was referring to?</FONT></DIV> <DIV><FONT face="Times New Roman"></FONT> </DIV> <DIV><FONT face="Times New Roman">Del</FONT></DIV></BODY></HTML>