Ron Nossaman wrote:
> >> >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.
At no time Ron, have we been discussing the difference between a tight radius "V"
and a wide Radius "V". We are talking about the difference between a "V" profile of
0.5 mm width (not rounded) and a "U" profile of a with a string contact point
(string not vibrating) of greater then 1mm.
>
>
> > 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 "V" profile described by Ed is a sharp "V".. not rounded at all. We do not have
two nominally round surfaces, we have one round and one not.. so I am afraid the
analogy does hold. I will allow you that nothing in this world is perfect, so one
would have to say the "V" profile approaches this ideal, where as the wide "U" moves
much further away from this ideal. You describe the reality of the "U" profile quite
well... and I quote
"Make yourself a see-saw by laying one round bar perpendicular on another and
see what you get."
This is exactly the point. In a "U" or clamped termination the "hinge" as you term
it does not exist. In the "V" it does (not absolutely, but to some significant
degree. (I have not seen the Wapin Bridge yet so I can not comment there) As far as
the see saw example is concerned... ok.. you jumped on the fact that the see saw
generally is hinged, and didnt see the point of the analogy. I'll repeat the one I
used a week ago, Take a round pencil and balance it on another round pencil, then
rock the system a bit, then do the same thing with a round pencil balanced on a
sharp straight edge. If you need to exagerate the sharpness of the straight edge to
get the point.. do so.
>
>
> >> 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.
But that is precisely what happens at the termination point (to a greater degree)
when the vibrational axis is not controlled (to a significant degree) The "V"
profile does this, the "U" does not. (again no absolutes here)
>
>
> > 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.
You take this out of context... the point really being how all this (the two
different profiles) relates to strings developing buzzes at the termination 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.
And I made and underlined that the rate of wear was the least of the concerns when
discussing the differences between the two profiles, and again we are disscussing a
"V" as opposed to a "U". Until you confront this difference, and how it effects the
behaviour of the load at the termination point, your argument remains unconvincing.
In any case I have made no comparisons of a wide radius "V" to a tight radius "V".
>
>
> >> 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.
This was simply a reference that you had changed the subject..and taken a point out
of context.. nothing more.
>
>
> Ron N
Now... as far as I can tell.. this aspect of Ed's book is well researched by him. I
have problems accepting that a fellow like Ed is going to do all the research
neccessary, write a book, publish it, sell it to others in the profession, and at
the same time make such an obvious and large blunder as it seems he is accused of.
This just doesnt add up. If I am going believe this, then some pretty good
argumentation and science has to be presented to rebuke his contentions. So far I
have seen the difference between a clamped and pivoted point described as a wide "V"
as opposed to a narrow "V", an over emphasising on the point about the rate of wear
on the capo bar, continued ignoring of the points dealing with string buzzing,
change in stiffness and inharmonicity, and over simplified notions of load
dispersion at terminations of vibrating systems that do not take into consideration
the change in the loads behaviour, but simply regard the "psi" factor.
If this was a football game, I'd have to say that midway through the 1st quarter
Ed's team has recovered a fumble, scored one field goal, and put about 130 yards of
offence on the books, where as the "blue team" has ... well fumbled. grin
Richard Brekne
I.C.P.T.G. N.P.T.F
Bergen, Norway
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