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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Why would you ever want to set the same
downbearing force per unison when the unisons are so unevenly distributed along
the length of the bridges? The top two sections of a typical concert
grand contain 43% of the strings on 20% of the total bridge length. A
smaller piano may have 46% of the strings on 29% of the bridge. Setting a
uniform downbearing per string will set up a tone-stifling imbalance in the
downbearing force along the bridges. For 20+ years I have been setting
downbearing on the principle of uniform force per unit of bridge length.
This produces much less force per string in the high treble and much more in
the tenor. I don’t measure angles. In Parts 5 & 6 of “Recapping
Bridges” in the 1999 Journal, I present a discussion of downbearing as
force, not dimension, and describe a method of setting a more uniform load
distribution. I’m sorry it’s too involved to go into detail
here. I know of one other rebuilder besides me who does something along
these lines.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>Bob Hohf<o:p></o:p></span></font></p>
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10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 color=black face=Tahoma><span
style='font-size:10.0pt;font-family:Tahoma;color:windowtext;font-weight:bold'>From:</span></font></b><font
size=2 color=black face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma;
color:windowtext'> caut-bounces@ptg.org [mailto:caut-bounces@ptg.org] <b><span
style='font-weight:bold'>On Behalf Of </span></b>RicB<br>
<b><span style='font-weight:bold'>Sent:</span></b> Saturday, April 28, 2007
3:04 AM<br>
<b><span style='font-weight:bold'>To:</span></b> caut@ptg.org<br>
<b><span style='font-weight:bold'>Subject:</span></b> [CAUT] Wire Stretch</span></font><font
color=black><span style='color:windowtext'><o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=3 color=black face="Times New Roman"><span
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=3 color=black face="Times New Roman"><span
style='font-size:12.0pt'>Yes they do what Bob ? Graduate downbearing
angles so as to get exactly the same amount of downbearing force on each unison
?<br>
<br>
RicB<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 color=black face="Times New Roman"><span
style='font-size:12.0pt'>>Course the problem with this notion is that equal
tension by no means <br>
(in fact dictates the opposite) of equal amounts of downbearing pressure <br>
across the scale unless one compensates by graduating the downbearing <br>
angle appropriatly...which I dont think anyone does.<<br>
<br>
<br>
<br>
Yes, they do. Check out your July and August 1999 Journals<br>
<br>
Bob Hohf<o:p></o:p></span></font></p>
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