High(!) touchweight

Newton Hunt nhunt@jagat.com
Wed Sep 16 10:45 MDT 1998


Ron the number of key weights is a dead giveaway.  You have a leverage
problem.

The way NY sets up their actions is to set the key frame to the case.
set the stack to the strings and locate the capstans to the wippens.
There are two places where a key leverage problem can occur.

In Germany they fit the stack to the keys the capstans to the wippens
THEN fit the action in the case and to the strings.  They get the action
right before putting it into the piano.  THey therefore have very
consistent actions.

Check the spread action measurement;  greater than 4.422 and not greater
than 4.440.

Hammer weight measured from perpendicular line through center pin to
center line of hammer with shank horizontal with frictionless contact
points with hammer resting on a digital scale.

David Stanwood has published hammer weights in terms of loud, medium and
soft tone with ranges.  These numbers subjects to quadratic equations
results in curves.  Plotting samples of your hammer weights will show
where they fall on these curves.

Based upon the six weights in the bass indicates there is a leverage
problem that may necessitate the relocation of the capstans by as much
as .125".

Pianoteck has all the tools needed to do this evaluation.

        Newton



This PTG archive page provided courtesy of Moy Piano Service, LLC