Lost motion: (was puzzler on M & H BB

[David Ilvedson]

That's the way I was taught but Yamaha teaches another way which I'm using.   Lay a piece of paper on a table and run you finger against the edge.    That is the feel you are looking for between the jack and the rep window.    In other words a hair below level.   I have no problem with hammer lever with that method.   Obviously you have to have adequate rep tension.    When using the "scrapping" method the jack does need to be able to get back to rest....imho

David Ilvedson, RPT
Pacifica, CA  94044


----- Original message ----------------------------------------
From: A440A at aol.com
To: pianotech at ptg.org
Received: 9/25/2006 9:02:25 AM
Subject: Lost motion: (was puzzler on M & H BB


> JD  writes:

><< Have you got the proper lost motion at the fly?  In other words does 

>the cradle support the hammer very slightly above the jack?  This 

>lost motion should be barely perceptible when you tap the key 

>lightly, but you must have lost motion so that the fly can return 

>under the roller without impediment. >>

>Greetings, 
>   I have to respectfully disagree with this.  Grand piano actions work 
>wonderfully with no lost motion, at all.  If there is any lost motion, there will 
>never be a straight hammer line as well as accelerated wear of the knuckle( 
>from the impact of the jack hitting it rather than pushing it to start.
>    We were taught at North Bennett to set the balancier so that we could 
>feel the jack scraping, ever so slightly, across the leather of the knuckle when 
>the hammer was at rest, and I have never had a problem with this causing loss 
>of repetition. 
>   Uprights are a different matter. 
>Regards, 
> 
>Ed Foote RPT 
>http://www.uk-piano.org/edfoote/index.html
>www.uk-piano.org/edfoote/well_tempered_piano.html
>