<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML style="FONT-SIZE: x-small; FONT-FAMILY: MS Sans Serif"><HEAD> <META http-equiv=Content-Type content="text/html; charset=iso-8859-1"> <META content="MSHTML 6.00.5730.11" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=#ffffff> <DIV><FONT face=Arial>Just recently worked on an old upright with similar problem.</FONT></DIV> <DIV><FONT face=Arial>The original hammers were tapered on both shoulders to avoid interfering with neighbors.</FONT></DIV> <DIV><FONT face=Arial>The manufacturer was trying to match the hammer angle to the bass string angle.</FONT></DIV> <DIV><FONT face=Arial>I boared the new ones at 6 degrees and was able to avoid tapering. A few trials at 7 through 20 degrees would cause interference problems. The new hammers were a bit larger than the originals.</FONT></DIV> <DIV><FONT face=Arial>I did not see the need to attempt to match hammer/string angle.</FONT></DIV> <DIV><FONT face=Arial>Gene</FONT></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=davespianotuning@earthlink.net href="mailto:davespianotuning@earthlink.net">Dave McKibben</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A title=pianotech@ptg.org href="mailto:pianotech@ptg.org">Pianotech</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, December 16, 2006 7:53 AM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> upright hammer bore angle</DIV> <DIV><BR></DIV> <P> <DIV>Hello all:</DIV> <DIV> </DIV> <DIV>Could someone explain, or lead to a book that explains how to figure out hammer bore angle on an upright piano.  I have an issue going on with regard to new hammers on an upright but the whole bass section does not work.  They interfere with each other before the hammer gets to the strings.  I suspect it has to do with shaft length, hammer blow distance and other measurements, but as you can see, I just don't know the details.  The problem is.........its always the details that mess ya  up :)</DIV> <DIV> </DIV> <DIV>Thanks much</DIV> <DIV> </DIV> <DIV><A href="mailto:DavesPianotuning@earthlink.net">DavesPianotuning@earthlink.net</A></DIV> <DIV><A href="http://www.home.earthlink.net/~davespianotuning/">http://www.home.earthlink.net/~davespianotuning/</A></DIV> <DIV>858-776-2516</DIV> <DIV> </DIV> <P></P></BLOCKQUOTE></BODY></HTML>