Knuckles

[David ilvedson]

I believe Yamaha has smooth side for the jack going out help 
with wear and tear on the knuckle.

David I.

Date sent:      	Thu, 02 Dec 1999 16:00:58 -0400
From:           	Michael Jorgensen <Michael.Jorgensen@cmich.edu>
To:             	pianotech@ptg.org
Subject:        	Re: Knuckles
Send reply to:  	pianotech@ptg.org

> 
> 
> Richard Brekne wrote: The jack
> 
> > moves in both directions across the knuckle...so which direction it
> > needs the smooth run, and why this is so
> 
> Rough moving toward the flange and smooth toward the hammer.
> This is supposed to give better grip for the jack so it doesn't skip out
> (cheat) as easily, and smooth toward the hammer should make it less
> resistant for easier jack return.  Since the fingers of a pianist are much
> stronger than a rep/jack spring they are better able to overcome the
> friction caused by this roughness.  I believe that some European Pianos
> reverse the nap direction with the thinking that it makes a smoother feel
> for the pianist and possibly quieter.
> -mike
> 
> 
> 


David Ilvedson, RPT
Pacifica, CA
ilvey@jps.net