bass string design

[John Gunderson]

Del,  oddly enough I tuned an identical piano today.  It was the same make and
there was a difference of less than 1000 between the serial #'s.  The scales
and plate markings were the same.  This other piano had already been restrung.
The bass strings were not like the original set I removed from my piano, my
piano having 12 double wrapped strings the other piano having only 8 double
wrapped string.  I took the opportunity to measure those strings.  Would you
believe that A0 had a core of .055" and the O/A diameter was .292".  The lowest
single wrap string (E1) had a core of .051 and an O/A of .200.  Actually, A0
didn't sound bad at all... given the small size of the piano.


John Gunderson, North Jersey Chapter

Delwin D Fandrich wrote:

> ----- Original Message -----
> From: John Gunderson <jgunderson@monmouth.com>
> To: <pianotech@ptg.org>
> Sent: Wednesday, August 04, 1999 5:55 AM
> Subject: bass string design
>
> > Thanks to all for the input.  I think that Del Fandrich provided the
> answer I
> > was looking for, that being that there is an optimum proportion of  core
> > diameter to o/a diameter.  Thinking about it, it make sense that as you
> bend a
> > wrapping around a core you are stressing the outter fibers of the
> wrapping.  The
> > tighter the bend, the greater the stress.  Eventually a point is reached
> where
> > the fiber structure is damaged and the wrapping is no good.  The two
> factors in
> > how tight you are "bending" are the core diameter (circumference) and the
> > wrapping radius (distance from the center).
> >
> > Thanks again for the advice...  Back to the drawing board.  JHG
> >
> >
> > John Gunderson, Associate Member, North Jersey Chapter
> >
> ----------------------------------------------
>
> John,
>
> That wasn't given as an "optimum."  More like a maximum.  I'm still working
> on the optimum part.
>
> Del