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<DIV><FONT face=Arial size=2>Hi Don,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Yes, I agree with you, when one =
is needs to
characterize the system accurately and not merely conceptualize =
it. You're
correct that the distribution of masses in the system is far from =
ideal.
</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>That aside, you raise an interesting
point...</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT size=2><FONT face="Courier New"><U><<Major =
Reason</U>: The
shank is also rigid, so the mass of the hammer head wouldn't even act =
from its
center of gravity <EM>even if the shank had zero mass</EM>. The =
center of
<EM>percussion</EM> of the whole hammer (which is nowhere close to the =
cg of the
head <EM>or</EM> the whole hammer) would determine its behaviour =
and a
non-trivial (though easily calculable) part of the impact =
would be
absorbed by the pivot itself as a result.
>></FONT></FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>YES! Which raises a point =
I've
scratched my head about. Why is the hammer aligned the way it is =
on the
shank? It makes no sense to me.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Probably any baseball player =
would know
that it's not smart to hit the ball with the very tip of the bat. =
It makes
for a nasty shock to the hands (and to the extent that the hands are not =
rigid
in space, it takes away from the power transferred to the ball). =
Why do
they do this with piano hammers? More to the point, is this not =
considered
an unneccessary demand to put on the hammer flanges and bushings? =
Perhaps
it's also a drain on efficiency? Wouldn't it make sense to have =
some sort
of asymmetrical molding whose center of mass is on the far side of the =
action
center, so as to put the center of mass of the hammer assembly closer to =
the
line of strike?</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Also, wouldn't it at least make =
sense to
angle the head of the hammer inwards slightly, so that the radius to the =
head's center of mass is perpendicular to the strike axis of the
head? It seems to me that this would help to control wobble in the =
hammer</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>I'm not sure I agree about part =
of the
impact being "absorbed" by the pivot. Sure, there would be force =
against
the pivot, but for impact to be absorbed, the pivot would need to be =
compliant
and inelastic. I realize that's true to an extent, as no system is =
ideal. However, do you think this would be a substantial drain of
energy? It seems to me that the hammer felt and the strings are =
far more
compliant and are closer to the center of mass, such that almost all of =
the
energy would be dissipated there (rather than at the comparatively rigid =
center). Have you ever measured this?</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Just curious on your =
take. I can't do
much more than scratch my head about this one. If the hammer were
perfectly rigid and the center bullet proof and noncompliant, there'd be =
nothing
to worry about. But considering that it does the hokey pokey and =
shimmies
all about... Well, I don't know.</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>Peace,</FONT></DIV>
<DIV><FONT face="Courier New" size=2>Sarah</FONT></DIV>
<DIV><FONT face="Courier New" size=2></FONT> </DIV>
<DIV><FONT face="Courier New" size=2>PS I do appreciate that =
you're not
being a "wise guy." I enjoy discussing this stuff too. It's =
been
forever since I took college physics, and I have to exercise the gray =
matter
every now and then to retain some fraction of what I learned. Of =
course I
studied physics before Isaac Newton came along... so that =
changed</FONT><FONT
face="Courier New" size=2> everything!! =
;-)</FONT></DIV></BODY></HTML>