[CAUT] lighter touchweight

[Richard Brekne]

Actually, this is not quite correct either.  The rep spring in play does 
basically the same thing it does when we hold the key down.  It pushes 
the two <<halfs > of the action it separates away from each other. Its 
just that when you hold the key down the only thing that can move is the 
hammer... upwards.  But it exerts exactly the same amount of force in 
each direction just the same. How much is released in either direction 
is another matter.  Under play the parts move away from each other 
relative to how much mass each half presents to the spring. If the key 
has enough effective mass.. then you can actually experience a slight 
rise in the hammer under normal play. Happens with often enough when the 
pianists fingers dont simply release the key or release it very slowly. 

As far as the whippens' weight.  True enough that 1 gram of whippen 
radius weight equals translates to roughly 0.5 grams of weight 
difference at the key.  Clear enough given by the following : Action 
Weight  = (SW x HR x WR) + WW.   Where Action Weight is what is sitting 
on the capstan.  That said... that is a static measurement.  I dont know 
of anyone who's looked all that closely at the dynamics of different 
whippen weights.  I wouldnt have any problem removing 2-3 grams of 
whippen radius weight.  It is after all a small gain (if gain means 
reduced Action Weight) and its quick and easy enough to do.

If you lower whippen mass and leave the spring as it was.. then there 
will most definitely be a change in repetition speed. The sum of the two 
halfs are reduced and so the spring has an easier time of it. Dark side 
of this moon tho is that for the same repetition spring strength, more 
will be felt fed back through the key.

Cheers
RicB




     > Greetings,
     >    I don't understand  how whippen weight relates to hammer rise,
    since
     > the only part of the whippen that moves during this rise is the
     > balancier.  More explanation, here, please...
     > Regards,
     >
     >
     > Ed Foote RPT


    It ought to improve repetition some, because there's slightly
    less mass in the wippen. Hammer rise doesn't have anything to
    do with repetition except as a handy visual aid for us to set
    spring strength on the bench. In play, the wippen and back of
    the key are pressed down and the hammer doesn't rise. Whether
    the repetition difference is enough to be worth the trouble is
    a subjective call.
    Ron N