flexing hammer shanks

[Stephen Birkett]

The recent discussion on filming the flex of hammer shanks is very
interesting. Please report on any developments on this project.

In the context of early pianos there is apparently a strong
correlation between good tone (esp. in the treble according to Paul
Poletti) and *extremely* thin shanks...thus avoiding the xylophone
trebles associated with bad restorations and bad modern copies. The
mechanics of the Viennese action are quite different from the modern
piano...applied force is on the opposite side of the pivot, hammer is
key-mounted, hammer heads very light (consequently smaller moment of
inertia for hammer/shank system), smaller mech. advantage of pivot
system etc. This must translate somehow into a requirement for
extremely thin (unless you've seen them you cannot imagine how thin
this means) shanks for good tone. There must be a similar connection
to shank flex and acceleration with the modern piano. This would make
an interesting comparitive study...ideal candidate for computer
simulation. Anyone interested in simulation of piano actions?

Stephen Birkett