Action Center Question

[Michael Magness]

On Wed, Apr 2, 2008 at 11:00 AM, Michael Magness <IFixPianos at yahoo.com>
wrote:

>
>
> On Tue, Apr 1, 2008 at 9:26 PM, <pianolady50 at peoplepc.com> wrote:
>
> >  Matthew,
> >
> > The hammer butt spring (disconnected in your photo) engages in the loop.
> >
> > Debbie Legg
> >
> > Okay, so I decided to spend some time this evening looking into my Yamaha U1 I bought last year.  The first thing I noticed was all the jacks are plastic.  Was that to save money?
> >
> >   And then I noticed something about the butt flanges.  I was in the process of taking a few hammer shank centers out and testing the center pins using the traditional method of swinging the hammer by holding the flange, when I noticed the following (click link).
> >
> >   http://farm3.static.flickr.com/2170/2381002693_3983592996_b.jpg
> >
> >   What is the purpose of the white string that loops around the flange?  I was unable to freely swing the hammers obviously, and I have not seen this before.  What is it's purpose?
> >
> >   Thank you for your help!
> > Matthew
> >
> > Sorry about the previous blank post.
>


>  Hi Matthew, what you are looking at is a copy of a Schwander action which
> differs from the average upright action, as you have noticed, by having
>
the hammer return spring built into the hammer butt rather than on a
seperate rail. Upon further examination of your action you will also notice
that it has a seperate jack slap rail, that is
adjustable rather than just padding on the back of the letoff adjustment
rail that usually serves as a jack slap rail on a regular vertical action.
The point of these features is to make this a
more accelerated vertical action than it's predecessors. I'm certain there
are other less obvious differences in the geometry of this action but these
are the 2 features that make it the most
recognizable. The Schwander action was patented and was owned by Kimball the
last I heard, I don't know if it was sold after they discontinued production
of pianos or not. It has been
widely copied by asian piano makers with minor variances to avoid having to
pay royalties.

Mike

>
>
>
>
> --
> The greatest challenge to any thinker is stating the problem in a way that
> will allow a solution.
> - Bertrand Russell
>
> Michael Magness
> Magness Piano Service
> 608-786-4404
> www.IFixPianos.com <http://www.ifixpianos.com/>
> email mike at ifixpianos.com




-- 
The greatest challenge to any thinker is stating the problem in a way that
will allow a solution.
- Bertrand Russell

Michael Magness
Magness Piano Service
608-786-4404
www.IFixPianos.com
email mike at ifixpianos.com
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