Inertia, was "Grand Touch"

[Bob Hull]

Splitting between the holes for lead inserts can also
come from improperly sized holes or a poorly supported
key during swaging.

The touch of a grand, or any piano for that matter,
needs to help the pianist in their expression and
control more than it helps us have neat charts and
formulas.  The more we discuss and experiment without
getting feedback from a variety of pianists, the
further away we can end up from the needed solution. 
This investigation seems so complex that I can only
imagine a dedicated research facility arriving at a
good solution.  

That's not to say that we shouldn't experiment and
discuss, but it could be a waste of time.  Are
pianists complaining a lot about touch issues for
which we don't already have enough workable solutions?
We are always trying to learn and improve and that is
definitely a good thing.

How about another method of weighting the key besides
cylinder shaped lead plugs.  While lead has the
advantage of weight and expandability, it is not good
to handle and it doesn't provide a
stiffening/strengthening factor like a harder material
could.
The harder material, perhaps in the the shape of a
plate, could also provide stiffness at the same time
as weight.  Also, perhaps a long plate would
distribute the added weight throughout a greater area,
if that is desirable. 

Bob Hull

--- Ron Nossaman <rnossaman at cox.net> wrote:

> 
> 
> > Ron N's fix of adding the hardwood shoe at the
> balance rail hole on the
> > other hand will make a huuuge difference. Why?
> Because he is increasing the
> > stiffness at the outer fibers where it does the
> most good: at the point of
> > the greatest weakness (balance rail hole goes
> through the outer web) where
> > the key is experiencing its greatest bending
> stress. My quick and dirty
> > calculations show the balance rail hole reduces
> the stiffness of the key at
> > that point of greatest strain by at least 40%.
> 
> As Mrs Hatfield always insisted (annoyingly), show
> your work. 
> Even so, the balance rail hole is a given (of
> sorts), and 
> increasing the "reduced from" stiffness with a
> nominally stock 
> balance rail hole produces a net gain in stiffness.
> This was 
> the intent.
> 
> 
> > The weakening effect of that balance rail hole on
> the keystick beam cannot
> > be overstated. It is the weak link in the system.
> The effect of any hole
> > drilled for leads pales in comparison.
> 
> As does, I suspect, the leading in the key compared
> to the 
> hammer weight that makes it necessary, which is what
> got us 
> here with the usual drift, in the first place.
> 
> 
> > I suspect cracks between the holes
> > occur not because of bending stress per se, but
> because of the internal
> > stress placed on the wood by swedging the leads in
> holes too close together.
> 
> "Too close together" being determined by the
> humidity swings 
> and the elastic limits of the material. Perpetually
> arguable 
> by an infinite number of the chronically uninformed.
> 
> 
> > But I've been wrong before. :-)
> > 
> > Dean
> 
> <G>
> 
> Ron N
> 


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com