bridges/seating

[John W. McKone]

Ron,

If you're asking why the string can creep up against the pressure of =
downbearing and friction, you need look no further than the impact of =
the hammer (on a grand anyway) Especially on a hard use piano.

John  McKone, RPT
St. Louis Park, Minnesota
(612) 280-8375


-----------------------------------------------
>From   : Ron Nossaman <nossaman@southwind.net>
Sent   : 04/08/97
To     : pianotech@byu.edu
Subject: Re: bridges/seating


Ok guys, you got me. But how is this possible unless the bridge pins are =
notched  by string wear or something? (Evil spirits? Trickle down =
economy? Oops, sorry, same thing.) I've chased a lot of false beats =
without being able to verify this phenomenon, bu

t "There are more things in Heaven and Earth..." etc. I sure would find =
it a lot easier to believe if there were a good plausible explanation. I =
always have had the need to look under the rock and decide for myself. =
Incidentally, I have seen string dents

in removed bridge pins that could account for the thing, but that =
wouldn't me the case in a piano with new bridges & strings. Hmmmm...

Well, (drat!) I guess that's the WHAT. Now, who's got the WHY?


Eschew obfuscation!

                                 Ron Nossaman


>
>> I don't think
>> it's possible for a string, with measurable positive bearing, to ride =
up a pin (against
>> tension), slanted to force the string down on the bridge (against =
side bearing), and
>> stay there until someone knocks it back down where it belongs.
>
>That's exactly what happens.  We had one Steinway D that was used in
>1981 by 78% of the competitors.  It was tuned and tuned and tuned
>constantly, so it was *very* stable as far as the tuning pin setting =
and
>string segment settling were concerned.  After a hard workout, when
>some unisons had drifted (only slightly, of course [;>, but
>understandably), Pris and I found that most of the time, the strings =
had
>been _knocked upwards_ on the bridge pins from the heavy playing.
>Lightly tapping the string down onto the bridge put the unison back
>virtually perfectly in tune.  Go figure!?!
>
<snip>
>
>Joel Rappaport
>Round Rock, Texas
>
>




>I, too, was very skeptical of this until a colleague did a =
demonstration at a PTG chapter
>meeting. He put a wire-handled mute between two strings in the treble =
and lightly tapped
>one of those strings at a 45-degree angle just in front of the bridge. =
The mute changed
>angle about 10 degrees. It's hard to see the string move but you can't =
miss what the mute
>does when the string settles!
>
>--
>Thomas A. Cole, RPT
>Santa Cruz, California
>
>
>


 Ron Nossaman