Bridge Seating (was Re: Where to notch a bridge, & relative effects ????? (Advice sought)

[Gene Nelson]

Probably a silly question but I am not certain if the calculations for 
bridge pin movement assume all types of string motion to include those 
longitudinal modes that can extend past the bridge?
Gene Nelson
----- Original Message ----- 
From: "Ron Nossaman" <rnossaman at cox.net>
To: "Pianotech List" <pianotech at ptg.org>
Sent: Sunday, September 10, 2006 4:49 PM
Subject: Re: Bridge Seating (was Re: Where to notch a bridge,& relative 
effects ????? (Advice sought)


>
>> I'm coming in late here, but has anyone explained why the strings have 
>> come
>> off the bridge surface and bear only on the bridge pin?  Ron N. has
>> addressed hoe the string is moved up off the bridge by the swelling of 
>> the
>> bridge-a humidity increase for sure.  How do the rest of the respondents
>> explain this movement?
>>
>> Paul C
>
>
> The strings haven't come off the bridge surface. The seasonal swelling, in 
> conjunction with the frictional resistance between the string and pin has 
> crushed the notch edge to somewhere below the natural string path. The 
> string is sitting quite firmly on the rest of the bridge surface. Strings 
> still do not climb bridge pins in real life.
>
> But yes, I would also like to hear what sort of magic makes strings 
> supposedly float up bridge pins.
>
> Ron N
>
>