[CAUT] restrung D

[Alan McCoy]

Hi Daniel,

Having just returned from the PNWC in SLC and taking a class from Ron
Nossman, my understanding of what is happening at the bridge-bridge pin-
string interface has been revised yet again. Like many others I was taught
to seat the strings by tapping gently on the top of the bridge right at each
pin. Then that was revised to tapping the string in front of the bridge
sideways toward the string. That was revised to tapping the bridge pin down
and not tapping the string down at all. Now however, Ron has presented a
compelling argument that tapping the pin down is a temporary fix at best
(feel free to jump in here Ron when you get back home from SLC). A couple
seasonal humidity shifts later and the pin will have risen back up. Not only
that, because the pin is at an angle, over the seasons the string pushes up
on the pin and in the process creats an oblong hole at the top of the bridge
surface (flagpoling of the pin). Result? False beats. Cure? Quick and dirty:
CA glue at side of pin opposite the string. Cure at rebuild? Very hard
bridge cap with pins epoxied in, but with the pin not seated in the hole.
The concept being that the tight fit of the pin at the surface of the bridge
is what counts, not whether the pin is seated at the bottom of the hole. In
fact, Ron says, a pin tight at the bottom, but flagpoling by a minute amount
at the top is still a source of false beats. So the idea of testing the
integrity of bridge pins by giving them a yank and assuming that, if they
are tight they are still good, may not be an accurate test.

BTW, regarding that nick in the side of the bridge pins (caused by the
string digging into it) that was the topic of a thread awhile back. Anyone
have any thoughts as to the effects of this nick on tone and tuning? I'm
guessing that the effect is negative for both (based on absolutely no
experiment!)  But if my guess is correct, would a harder material for bridge
pins be a good idea? Bridge pins are probably #2 steel plated with either
copper or nickel, and nickel is harder than copper, right?

Talk about long-winded.

Thoughts anyone?

Alan

-- Alan McCoy, RPT
Eastern Washington University
amccoy at mail.ewu.edu
509-359-4627


> From: Daniel Gurnee <dgurnee at humboldt1.com>
> Reply-To: "College and University Technicians <caut at ptg.org>" <caut at ptg.org>
> Date: Mon, 09 Apr 2007 21:08:19 -0700
> To: "College and University Technicians <caut at ptg.org>" <caut at ptg.org>
> Subject: Re: [CAUT] restrung D
> 
> Alan,
> 
> I have found bridges indented at the front bridge pin by that process
> of impressing the string in front of the bridge pin which allows the
> string at the front bridge pin to rise from the bridge surface as it is
> pulled to straight from the higher center on the bridge to the upper
> bearing.  As pianos become aged and heavily played the bridge may
> become indented at the front bridge pin but the present day has shown
> much more incidence from the practice of "setting the string onto the
> bridge.
> 
> I used to set the string onto the bridge but my process was to roll
> across the strings close to the bridge from bass to treble with as
> little pressure as possible but to produce the result of getting the
> string just to the bridge top.  That also tended to settle the string
> into the crotch of the  bridge pin and bridge top.  It has been noted
> not too long ago I believe by Jim Ellis, (Please correct me if I am
> wrong) that string wear on the pin also tends to raise the string off
> the bridge so that driving the pin down so that the upper angle of the
> wear will tend to capture the string pulling it to the bridge top.
> 
> I will now accept admonitions about long winded admonitions,
> 
> Daniel Gurnee, RPT, HSU Ret.
> 
> 
> 
> On Monday, April 9, 2007, at 11:41 AM, Alan McCoy wrote:
> 
>> Daniel,
>> 
>> Do I understand correctly that you are tapping the string down onto the
>> bridge in the middle of the bridge between the pins. Do you do this in
>> addition to (or instead of) tapping the string toward the pin near
>> each pin
>> just off the bridge?
>> 
>> Alan
>> 
>> 
>> -- Alan McCoy, RPT
>> Eastern Washington University
>> amccoy at mail.ewu.edu
>> 509-359-4627
>> 
>> 
>>> 
>>> In approximately one/half of the cases of "false" strings, a
>>> correction
>>> may be more quickly made by driving the string into the middle of the
>>> bridge making a straight line contact of string to bridge from the
>>> front pin to the back pin.
>>> 
>>> Daniel Gurnee, RPT, HSU Retired.
>>> 
>> 
>> 
>> 
>