Shigeru Kawai regulation

[Kevin E. Ramsey]

    Hello, Dan. I agree, the rep lever gets taken out of the equation once
it contacts the drop screw; hence the term "double escapement". It's my
understanding of it that the jack should begin escaping at the same time
that the drop screw contacts the balancier.
    However, I wonder really how much of a contribution the rep lever makes
to the movement of the hammer anyway; not much I would think, given the
relatively weak condition of the spring compared to the accelerating force.
Interesting to think about it, anyway.
    Usually, when I see too much drop on a new piano, it's because there is
just too much aftertouch in the action, and the people at the factory put
that much drop into it so that the hammer can't rise up so high in the
aftertouch phase to block against the string. Easier than putting in more
punchings, y'know.


----- Original Message -----
From: "thepianoarts" <thepianoarts@home.com>
To: <pianotech@ptg.org>
Sent: Sunday, September 09, 2001 10:50 PM
Subject: Re: Shigeru Kawai regulation


> Hello Kevin,
>
> This is a great area for study, yes?
> Do you agree that the rep lever is not involved in lifting the knuckle/
> hammer after the drop screw contacts the rep lever?
> Dan
>
>
>
> on 9/9/01 10:32 PM, Kevin E. Ramsey at ramsey@extremezone.com wrote:
> >SNIP "What happens if the rep lever contacts the drop
> > screw too soon? Then the jack continues to lift the knuckle further up
all
> > by its self, resulting in a draggy feeling at the end of the key
stroke."
> >
> > ----- Original Message -----
> > From: "thepianoarts" <thepianoarts@home.com>
> > To: <pianotech@ptg.org>
> > Sent: Saturday, September 08, 2001 9:36 PM
> > Subject: Shigeru Kawai regulation
> >
> >
> >>
> >> The technicians in the Dallas/ Ft.Worth Texas part of the world were
> >> treated to a technical this past week, on the refinments of the Shigeru
> >> Kawai, their preimer piano line. The technician who follows a
particular
> >> instrument through the facory, also goes to the new owners home to
service
> >> it. I guess that is a one time deal, since all the techs are coming
from
> >> Japan. Very impressive. Any other manufactures doing that? I love it
when
> >> someone raises the bar.
> >>
> >> There are a couple of regulation differences that are interesting.
> >> #1-Drop is set slightly early, and #2- jack height to rep lever height
is
> >> set so that there is no winking. The distance (jack height to rep lever
> >> top) is subtle, so as not to cause a hammer line wave.
> >> I beleive the reasoning for the earlier than usual drop, is that there
> >> is a smoother feel if drop and let-off are spaced slightly.
> >> Also, I beleive their thinking is, an earlier drop allows a safety
> > net
> >> which insures a positive 'scrape' or contact by the jack, which would
be
> >> reduced if the drop timing is later that the let-off timing. In other
> >> words, let the jack do it's job of lifting the hammer. Keep the spring
> >> loaded rep lever out of the picture.
> >>
> >> Dan
> >>
> >>
> >