tapping strings

[Richard Brekne]

Ok... I like this response quite a bit and feel much better ... a few comments
and points below..

Ron Nossaman wrote:

> >Ok... I have always understood you to mean that the string really isnt being
> >pushed
> >up the pin at all. Fair enough.
>
> Never, quite the opposite. I posted a message just yesterday, responding to
> you, giving you psi load figures on static load vs loads resulting from the
> bridge pushing a string up a pin. The post with which I responded to Ron T,
> your exception to which prompted yesterday's, again clearly stated that
> strings are pushed up bridge pins by the expanding bridge. What I've said
> is that it doesn't stay up the pin without contact with the bridge cap.

You wrote just a few days ago.. and I quote

" Nope. The string doesn't climb off of the bridge top, and the pin doesn't climb
out of it's hole"

Similar formulations are easy enough to find... tho with a closer reading of each
post I have found so far I see its easy enough to interpret these in the light
you now underline.... you'll excuse and understand I hope that I have up to now
assumed you meant the pins were not pushed up the pin at all. Now that that is
out of the way......grin...


>
>
> >Now that I am past that I still end up with the position that as long as the
> >lowest
> >part of the indentation is above the string line, taken as the angle created
> >by the
> >difference of the height of the  center of the bridge visa vi the front
> >termination
> >point, then any seating that can be accomplished is and should be advisable.
>
> I must not have explained this very well last time, so I'll try again. The
> string line isn't from the agraffe to the center of the bridge. It is from
> the agraffe to the highest point (first contact point) on the bridge cap.

????.... This is a point I am going to have to think through.... I keep
visualizing the center of the bridge as being the real high point of the strings
ideal arc if you will. In that view then what I have describe must hold true. And
in this sense I have often wondered why bridges are not "crowned" as it were to
meet that arc in a more natural fashion. That would seem to me to equalize to a
large degree the upward pressure on the string..... but ok.....

grin... You have given me something to ponder on this time.. :)

>
> In a well set up new bridge, that will be the notch edge. After that edge
> is crushed enough by bridge movement with seasonal changes (and/or
> unnatural abuse), that high point will be back on the bridge cap away from
> the notch edge. The termination on the bridge top will no longer coincide
> with the pin,

That would have to depend again on whether the notch/ bridge pin location is
lower then the line drawn between the new highpoint and the agraffe... if the
string has simply "drawn" a flatter line across the bridge then the string will
still terminate at the bridge pin....tho perhaps a little less efficiently.... I
am beginning to follow you a bit longer down this road tho...


> and if the pin is even a little bit loose, false beats will
> result.

Here we have always been in agreement.

> Seating the string at the pin just temporarily springs the string
> down to seat on the bridge at the pin. The string will soon be back where
> it was, and nothing will have been gained by seating the string.

As long as there is negative bearing at the exact point of the bridge pin...
ok... I can buy that easily enough.

> >As far as the distinctive kind of false beating loose pins cause we have
> >been in
> >agreement all along, but that is only one kind of falsness.
>
> I am well aware of this, and as I have said: I am talking about the usual
> run-of-the-mill loose bridge pin caused false beats that almost universally
> prompt tuners to get out their string seating tools and seat strings. I
> have never said, and never will say that what I am discussing here is the
> cause of all conceivable sound anomalies we have ever, or will ever come
> across in pianos. I am, once again, talking about those ubiquitous false
> beats that, when a screwdriver tip is placed against the side of the pin -
> clear up until the screwdriver is removed.
>
> Ron N

Ok.. I feel a lot more comfortable with all this now. So when do we start dealing
with why the condition of << positive bearing at the bridge pin simultaneous with
the string being off the cap at this point >> sometimes pops up ?

Many thanks for clearing this up for me... you've had me really scratching my
head on this one for quite some time.

Cheers !

RicB
--
Richard Brekne
RPT, N.P.T.F.
Bergen, Norway
mailto:rbrekne@broadpark.no
http://home.broadpark.no/~rbrekne/ricmain.html