bridge pin material

[David Love]

Ron:  I don't know, I didn't pull them out to measure them.  I only
resecured a few that were loose in bass section.

But am I mistaken or did I not hear you talk about the problems with string
cuts in bridge pins in your class in Reno.  It was my understanding from
your lecture that cuts in the bridge pins combined with the
expansion/contraction of the bridge cap over time prevented proper seating
of the string on top of the bridge.  A problem exacerbated by tapping down
the strings and one that leads to poor intonation, i.e. false beats.
Please correct me if I am mistaken.

That being said, why not use a bridge pin more impervious to cutting,
assuming, of course, that it is not so hard as to cut the string.

David Love
----- Original Message -----
From: "Ron Nossaman" <RNossaman@KSCABLE.com>
To: <pianotech@ptg.org>
Sent: August 13, 2001 8:25 PM
Subject: Re: bridge pin material


>
> >
> > David,
> >
> > I'm amazed no one else replied to your post (at least not to the list).
Mine
> > isn't much of a response, but I guess everyone agrees that the material
has
> > to at least be softer than the wire.  Better to have grooves in the pin
than
> > in the wire.  Why not brass or bronze?  Better rendering?  I don't know.
> >
> > Along the same line, Boesendorfer now uses an agraffe with a steel wire
> > driven through it above the holes to reinforce them.  It can't possibly
make
> > the brass any stronger, and if the string cuts through to the steel then
it's
> > liable to mar the string.  What's the thinking there?
> >
> > Fazioli uses a bronze rod set in a groove in its capo section.  I think
> > bearing material is a great subject for discussion.
> >
> > Paul Larudee
> >
> > David Love wrote:
> >>
> >> I discovered on this piano I'm restringing (Schiedmayer c 1910) that
the
> >> bridge pins are made from nails.  It brings up a question I've had.
Since
> >> false beat problems often arise from eventual cuts made in the side of
the
> >> bridge pin, why are they made of such soft material as copper (though a
> >> guess they are actually "coppered", or some kind of alloy).   What
other
> >> material are used, if any, and what is the cost/benefit of those
materials?
> >> David Love
> >
>
>
>
> The original never showed up in my box, just this. So...
> First off, I don't know that false beats often originate from "cuts"
(wear,
> abrasions, erosion, cavitation) in bridge pins. I'd put loose pins first
on the
> list, with wear and accompanying deformation of the pins as a supportive
> second. Most bridge pins we see are probably steel (plated), with brass
(plated
> or otherwise) as the second most prevalent. I don't know that there have
ever
> been copper pins installed in anything. Brass is more lubricious than
steel,
> but is softer (obviously), and more expensive, so the cost/benefit is
mostly in
> the perception of the builder. Nails should work at least as well as
anything
> else with the heads trimmed off , but won't have the corrosion resistance
of
> brass (plated or otherwise), or plated steel. What diameters are the nails
in
> your Schiedmayer  bridge?
>
> Ron N