[pianotech] Increasing bridge height

David Love davidlovepianos at comcast.net
Tue Mar 24 16:18:21 PDT 2009


But isn't that what we're talking about?  Raising the plate height and
thereby the string height and then changing the bore distance to accommodate
that change.  Does the action ration change then?  I can see where if you
simply changed the bore distance and left everything else alone but in this
case doesn't the leverage remain the same?

 

David Love

www.davidlovepianos.com

 

From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Jude Reveley/Absolute Piano
Sent: Tuesday, March 24, 2009 1:33 PM
To: pianotech at ptg.org
Subject: Re: [pianotech] Increasing bridge height

 

To the best of my knowledge, changing the bore distance changes the shank
upper lever arm and thus the hammer shank ratio. This changes the movement
at the knuckle, the lift at the capstan and the key leverage. Unfortunately
and most unconveniently for the sake of simple trig, the shank angle at rest
is only equivalent to the shank upper lever arm when the bore distance is
equal to the blow distance.

 

 

Humbly submitted,

 

Jude Reveley, RPT
Absolute Piano Restoration, LLC
Lowell, Massachusetts
(978) 323-4545

----- Original Message ----- 

From: David Love <mailto:davidlovepianos at comcast.net>  

To: pianotech at ptg.org 

Sent: Tuesday, March 24, 2009 2:24 PM

Subject: Re: [pianotech] Increasing bridge height

 

It does?  How.  If you raise the string plane and increase the bore distance
accordingly so that the shank angle at rest is the same as it was before,
how does the leverage change?

 

David Love

www.davidlovepianos.com

 


Of course, changing the bore distance does affect the entire action
leverage...

 

Jude Reveley, RPT
Absolute Piano Restoration, LLC
Lowell, Massachusetts
(978) 323-4545

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090324/f550ec39/attachment.html>


More information about the pianotech mailing list

This PTG archive page provided courtesy of Moy Piano Service, LLC