Regulation question

[A440A at aol.com]

<< What causes a key to "bounce"? In that, when the key is pressed and  
then it returns there is a little bounce up and down. What can be  
done to minimise this? >>

Greetings, 
   This is a common symptom of a key with too much lead in it.  You may need 
lighter hammers and less lead. 
Regards, 
 
Ed Foote RPT 
http://www.uk-piano.org/edfoote/index.html
www.uk-piano.org/edfoote/well_tempered_piano.html