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<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2>Ed,</FONT></SPAN></DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2>thanks
for this excellent research. </FONT></SPAN></DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2>I've
been keeping your post on my screen, in hopes that others better =
equipped to
discuss this with you would respond, this is such a cool
idea!</FONT></SPAN></DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2>I hope
you will keep us in the loop Ed. </FONT></SPAN></DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2>For
the meantime, I appreciate you pushing through with the experiment, and =
look
forward to future discussions when more of our colleagues =
are on
hand.</FONT></SPAN></DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2>Mark
Cramer,</FONT></SPAN></DIV>
<DIV><SPAN class=710540918-14062004><FONT face=Arial color=#0000ff =
size=2>Brandon University</FONT></SPAN></DIV>
<DIV><SPAN class=710540918-14062004> </SPAN></DIV>
<BLOCKQUOTE dir=ltr style="MARGIN-RIGHT: 0px">
<DIV class=OutlookMessageHeader dir=ltr align=left><FONT =
face=Tahoma
size=2>-----Original Message-----<BR><B>From:</B> =
caut-bounces@ptg.org
[mailto:caut-bounces@ptg.org]<B>On Behalf Of </B>Ed =
Sutton<BR><B>Sent:</B>
Wednesday, June 09, 2004 1:35 PM<BR><B>To:</B> =
Caut@ptg.org<BR><B>Subject:</B>
Weighing off by balance weight<BR><BR></FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2>Dear List-</FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2></FONT> </DIV>
<DIV><FONT face="MS Sans Serif" size=2>During our discussion of =
inertia in
piano actions a few months ago, Jim Ellis presented some of his =
thoughts on
the problem, including the suggestion that weighing off should be done =
relative to a target balance weight.</FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2></FONT> </DIV>
<DIV><FONT face="MS Sans Serif" size=2>I liked his thoughts, and =
intended to
try them as soon as I could. Opportunity came in the form of a =
small
Knabe action in which just about every design decision was =
wrong.</FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2></FONT> </DIV>
<DIV><FONT face="MS Sans Serif" size=2>To interpret Jim's idea, I =
made three
pairs of weights, representing varying amounts of friction with a 37.5 =
gram
balance weight, thus: <FONT size=2>25u+25=50d; 22.5u+30=52.5d;
20u+35=55d. In each weight pair, the first weight is the =
upweight, the
second added to it produces the associated downweight.
</FONT></FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2></FONT> </DIV>
<DIV><FONT face="MS Sans Serif" size=2>I found these weights =
delightful to
work with, as they enable you to assess the action in terms of =
relative
speeds. The goal is to produce equal speeds of and down =
movement
for each pair, but faster as you compare the 25/50 weights with the =
22.5/52.5
weights and then the 20/55 weights.</FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2></FONT> </DIV>
<DIV><FONT face="MS Sans Serif" size=2>On this action I made =
several
geometry changes (increased the hammer weight, shortened the wippen
heels, changed the capstan angle and finally moved the =
natural
capstans forward to equalize the key ratios with the =
accidentals).
Observation with the weight pairs made the improvements of each change =
very
obvious.</FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2> </FONT></DIV>
<DIV><FONT face="MS Sans Serif" size=2>Finally they led me on a =
fine chase for
tiny friction devils. Seeing the action move this way makes tiny =
moments
of friction easy to spot. For instance, things may move smoothly =
with
the 55 and 52.5 gram pairs, but there will be a slight =
delay with
the 50 gram downweight. This could be just a fuzz between =
wippens or a
rough place on a keypin. </FONT> <FONT size=2><FONT
face="MS Sans Serif"> </FONT></FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2><FONT face="Microsoft Sans Serif">Although it =
may seem
complex in description, in practice it was a fast and easy way to work =
through
the weigh off. Comparing the speed of hammer movement with two =
pairs of
weights gives very clear information. The amount of time spent
wondering, subtracting and second-guessing was
minimal.</FONT></FONT></DIV>
<DIV><FONT size=2><FONT face="Microsoft Sans =
Serif"></FONT></FONT> </DIV>
<DIV><FONT size=2><FONT face="Microsoft Sans Serif">My hat's off =
to Jim for
this idea.</FONT></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face="Microsoft Sans Serif" size=2>Ed =
Sutton</FONT> <FONT
size=2></FONT></DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face=Arial color=#0000ff size=2></FONT> </DIV>
<DIV><FONT face="MS Sans Serif"
size=2></FONT> </DIV></BLOCKQUOTE></BODY></HTML>