pianotech-digest V1997 #1919 (long)

Ron Nossaman nossaman@SOUTHWIND.NET
Wed, 1 Sep 1999 09:02:29 -0500 (CDT)


>> >Grin ...I can only report the information and arguments as I read them,
>> Ron, but
>> >they make sense to me. The wear and tear on the capo by the string is of
>> different
>> >character if the capo is more a "clamped" termination then a "Pivot"  Your
>> "longer
>> >support area" for a given load analogy doesnt really hold true. The "given
>> load" is
>> >not there at all. The "load" is in fact different in each case, by virtue
>> of the
>> >fact that the "load" behaves differently in each case.
>>
>>  Metaphysics aside, how can a bearing load resulting from a given string
>> tension, at a given deflection angle not be the same in either case?
>
>What does metaphysics have to do with it ? 

* Exactly what I was wondering. The psi load with a tight radius V is not
only greater than on a wide radius V, it's more damaging *because* of the
pivoting action. Most of the contact surface between a string and a wide
radius V is much less disturbed during play. Lighter psi load, less
movement, less wear. The trade off is in the precision of the termination.  


> It can differ due to differences in the
>strings vibrational axis. The clamped termination will be different then
the pivot
>termination. Er.. isnt a pivot just that.. a pivot. You dont pivot on a
pivot in any
>other direction then that of the pivot. You ever try to make a see-saw go
sideways

* If you have a string pivoting on a small radius V, then you have only a
single tangential contact point between two nominally round surfaces. There
is no hinge, so the analogy doesn't work. Make yourself a see-saw by laying
one round bar perpendicular on another and see what you get. Better yet,
bend the top bar in the middle at about 15 degrees to more closely simulate
the string and see how directionally limited the resulting pivot action is.
Alternately, you could hinge your strings to the V. Perhaps a Wapin V!



>> The "twisting" was an illustration in relation to the subject of a footprint,
>> which you brought up.

* Yes, in the context of load density, not shuffling feet on a giant V.



> In reality neither twisting or footprints have any bearing
>> on the subject, which was my point. 

* In my reality, the footprint of the string on the V has a very great deal
to do with determining wear rate of the V, which still is my point.




>Let me understand this correctly, do you
>> dispute that a vibrating string will behave differently when under a
pivot then
>> when under a clamped termination point ??? Does this not then in turn
directly
>> relate to how the point of contact will react to this difference in
behavior ??

* I never once even implied that the type of termination wouldn't affect the
behavior of the string. It obviously does. It was my impression that we were
discussing wear rates on Vs. You made the statement, second hand via Ed M,
that a wide radius V would wear faster than a tight radius V and I took
exception. Still do.




>>  Wear of the capo? Why? The *internal* friction increase would be in the
>> string, wouldn't it?
>
>the internal friction increase is the other side of the coin. That point
was not
>made in the section you site here.

* I have no idea what you are talking about.


 Ron N



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