Key Leads and Inertia

David C. Stanwood stanwood@tiac.net
Mon, 28 Apr 2003 12:56:48 -0400


>Let's say I measure a note on a grand action and 
>find that there is 12g of friction measured statically (D-U/2). When the 
>action is played through its dynamic range does the friction go up 
>proportionally to the increased force applied to the key?
>
>John Hartman RPT

John and Stephen,

Try simulating dynamic friction by attaching weight onto the hammer then
Measure U/D and calculate friction.   Tie down the jack so it stays under
the knuckle when measuring UpWt.  I'd use maybe a 50 gram weight....

David Stanwood

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