Checks cause hammer bounce ?

[RicB]

Hi Jon

I'm still at the head scratching bit... :)  What I know is that if I 
hold the hammer shank up beyond where it would contact the back check, 
and hit the key hard... there is no hammer bouncing by the neighboring 
hammers. But the as I lower it to allow some contact... bouncing 
starts... and when I just let it check as normal there is a good deal of 
bouncing.  So it has to do with how much hammer force hits the check.

Now as far as my mind has delved into this so far... that stresses the 
balance rail as the key front is held down by the finger, and the hammer 
hits the check which essentially exerts a force on the back of the 
key... which gets transfered to the only thing stopping  the key from 
moving with that force... namely the balance rail. Yet the balance rail 
is stiff and bedding screws are good.

I suppose the re-bound flex of the key being played thus could send some 
force back up the whippen cushion.... but would the fact that the check 
holds against the rebound flex in the key be enough to stress the 
whippen rail enough to cause more then just a little bounce ?

Grin... I just love these head scratchers.  I'm going to try coupling 
the hammer rail to the left off rail as per your instructions.... I'll 
let you know if that helps.

Thanks for your thoughts... keep em comming.

Cheers
RicB


    Could it be the whippen rail flexing?
    -- 

    Regards,

    Jon Page