Hammer angle rebound and pinning

[Richard Moody]

Even if a tilted, canted nodded hammer could hit the string
squarely, the rebound I  imagine would be toward one direction or
another depending on the angle, thus putting that much more stress
and strain on one bushing than the other.
    The idea that tightness of centers affect tone is intriguing.
This assumes both centers are the same firmness and resistance but
how do you determine that?   I can watch hammers fall from
vertical or take them off and do the screw test or swing test but
I imagine I am only seeing the results of the tightest center.
    Only when I repin do I know how both centers were and
subsequently are.
    So my question is, do those who repin for tonal improvement
find that one center is looser than the other, or are they more or
less the same?
---rm

----- Original Message -----
From: Roger Jolly <roger.j@sasktel.net>
To: Pianotech <pianotech@ptg.org>
Sent: Monday, March 17, 2003 7:44 PM
Subject: Re: more Rake Angle stuff



> > > >In a real piano, be it grand or vertical, in
> > > today's world, there is no
> > > way
> > > >to make the crown of the hammer hit the string in a
> > > perfectly
> > > perpendicular
> > > >direction.  You just can't do it.....
> > > >
> > > >Sincerely, Jim Ellis
>
> Hi Jim,
>               Absolutely correct.   Depending on the inertial of
a given
> hammer, and the force of the blow, it causes the shank to first
bend,
> before the hammer is set in motion.
> SloMo studies of action parts conclusively show that the hammer
rarely hits  the string square on.  The whip lash of the shank,
will cause the hammer to slightly over or under
> centre.
>
> Regards Roger
>
I know all this is true.  The shank flexes, the hammer doesn't hit
squarely, etc. yet we like the sound we get.  I wonder if we
really
could get the hammer to strike squarely if we would like the sound
it
made.

dave