[CAUT] Shank Pitch

[Porritt, David]

I'm not being contrary but when you walk up to a piano and play it can
you tell a difference if the person who hung the hammers didn't tune the
shanks?

Sincere question.

dp

David M. Porritt, RPT
dporritt at smu.edu

-----Original Message-----
From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of
Chris Solliday
Sent: Friday, February 22, 2008 9:55 AM
To: College and University Technicians
Subject: Re: [CAUT] Shank Pitch

maybe what they are doing at the Bluthner factory is different from what
I
do but when I remove material the pitch goes up in my scratch test.
Perhaps
this is not the  best test.
Chris Solliday
----- Original Message ----- 
From: "Ron Nossaman" <rnossaman at cox.net>
To: "College and University Technicians" <caut at ptg.org>
Sent: Friday, February 22, 2008 10:25 AM
Subject: Re: [CAUT] Shank Pitch


>
> > Chris & all
> >
> > I do know that to lower the pitch on a reed organ reed you scrape
> > material from the bass end of the reed making the mass of the end of
the
> > tongue heavier in relation to the overall reed and the pitch goes
down.
> > I have never tried it on a hammer shank but I can see where the same
> > principle would apply.
> >
> > Norman Cantrell
>
> Hi Norman,
> In the organ reed, scraping the tip of the reed removes mass,
> raising pitch. Scraping the base end of the reed decreases
> stiffness, lowering pitch.
>
> Resonant frequency in anything is determined by a combination
> of stiffness and mass. In the case of hammer shanks, it would
> appear from the reported results that the loss of mass
> realized in thinning has a greater affect on "doink" pitch
> than the loss of stiffness.
>
> I don't tune shanks, so I wasn't aware of this. I would have
> expected the shank pitch to drop. Interesting.
> Ron N