Lost Motion and Touchweight

Jon Page jonpage@attbi.com
Tue, 03 Sep 2002 20:37:47 -0400


At 05:03 PM 9/3/2002 -0700, you wrote:
>Hello all: I got a call today from a customer whose Knabe console I serviced
>at the end of July. She complained that something I did has made the piano
>have a very heavy touch, not only to her but to her husband, and she wants
>it put back to its former condition. I looked up my record on the piano and
>saw that aside from tuning it I adjusted the lost motion.  I have never had
>anyone complain about the piano having a heavy touch after having the lost
>motion adjusted. My experience has been that the piano plays better, and
>previous tuners may have been ignoring the need for the lost motion to be
>taken up.  She says that she has had it maintained by well respected
>technicians where ever she has lived, the last one being the technician for
>a Steinway dealer. She has moved out of his service area, which is why she
>called me.  I am at loss to figure out how taking up the lost motion could
>make a piano have an uncomfortable heavy touch.  My guess is that she had
>grown accustomed to playing an out of adjustment action, and that a properly
>adjusted action with a firm touch feels "heavy" to her.  I have an
>appointment tomorrow morning to check the piano over and do what is
>appropriate to satisfy her, but I'm scratching my head as to how to put the
>piano back out of adjustment in order to satisfy her. Has anyone run into a
>similiar situation?  My notes do not mention any sluggishness or tightness
>in the flanges, and she says she noticed this change in the touch
>immediately.
>Thanks, Patrick Poulson, RPT

It could be the heightened humidity this summer causing sluggishness which
is interpreted and heavy. It may have even raised the hammer shanks off the 
rail
depending on how much lost motion you didn't leave in.  When you pull back on
the rail, the hammer should follow and not be held by the jacks.

Bring some action cloth to raise the hammer rail to induce lost motion. 
This will save you
from turning the capstans down. The hammer blow could probably stand a 
little less travel too.

By reducing the lost motion, you raised the wippens. This brings the damper 
spoons closer to the dampers
and will cause them to lift sooner in the key stroke, sometimes even 
liftling the dampers at rest off the strings.
DAMHIK.

So look at damper timing as well, if it's too soon in the keystroke, it 
adds the spring resistance earlier = heavier.


Regards,

Jon Page,   piano technician
Harwich Port, Cape Cod, Mass.
mailto:jonpage@attbi.com
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