Piano Size & Shape

[Delwin D Fandrich]

----- Original Message -----
From: "Phillip L Ford" <fordpiano@lycos.com>
To: <pianotech@ptg.org>
Sent: December 03, 2001 1:54 AM
Subject: Re: Piano Size & Shape


>
> When you say that all the strings were angled toward the
> center of the board does that mean the strings at the top
> end are angled to the left and the strings at the bottom
> end are angled to the right?  Or are all the strings angled
> to the right?

As I recall--and, please, this was nearly 30 years ago--C-88 was
perpendicular to the stretcher and the front of the piano. In my memory from
that point they all angled a bit to the right. A-1 had an angle to the
stretcher about like that of, say, a typical 9' overstrung piano. There were
two bridges with a typical offset between the plain tri-chords and the
wrapped strings. I don't really remember the scale all that well except to
say that at the time I did record it and work out a new bass and tenor
scale. One of the last I did by slide rule. My HeathKit calculator took over
shortly thereafter.



> Why would there be more load on the bridge
> pins with this design than with a conventional design?  It
> seems that if the string makes a straight line from the
> tuning pin to the hitch pin then the displacement caused
> by the bridge pins would be the only thing causing load
> on the bridge pins.  It seems this would be the same whether
> the string was straight or angled.

It wasn't the loading of the strings or their angles that caused the
problem. It was the spacing between the pins. Both the pin spread and the
unison center-to-center spacing were crowded. Picture this in comparison to
the typical overstrung string dispersion in which the string centers spread
apart and the pin spacing is rather wide. The crowding of the pins had
caused a great deal of splitting on the original bridge. I recall making a
laminated cap using maple veneers, but lost track of the instrument a couple
of years after the job was finished so I don't know how it has held up over
the years.

Del