Hornbeam

[Delwin D Fandrich]

Frank Weston wrote:

> >As close as they could be, yes.  The hex shank is not inherently stiffer
> >than a round shank of the same relative diameter.  The best shape for
> >hammershanks, of course, is rectangular.
>
> This statement assumes that we know the optimum stiffness for all
> hammershanks and for each specific hammershank.  Is stiffer always better or
> is there an optimum match between stiffness, hammer weight, action geometry,
> humidity and phase of the moon?  Where does impedance play in the equation?

What do you mean by 'impedance' in this context?


> If lighter and stiffer is always better (as I assumed when I was a younger
> man), then the optimum shape for a hammershank would be an I-beam.

True, if the shank were made from some material other than wood -- of any
variety.  And if all of the forces acting on it were exactly in line with the
centerline of the shank -- i.e., no rotational forces of any kind.  This is not
the case in the piano action.


> Renner have made some pretty good arguments as to why they use Hornbeam, and
> they do seem to say they will make parts of maple should a customer request.
> The cost of materials in the manufacture of action parts is a pretty small
> part of the equation, and machinability is a good argument since it results
> in better parts.

One would think.  Unfortunately, the last time I checked -- and it was quite
some time back -- the cost of Renner hammershanks made of maple was way out of
line with the added cost of the material.  Presumably because it would upset the
production flow.  It probably would be something of a hassle for them to switch
back and forth.  But I think to a large extent it simply because didn't want to
do it.  (A ploy which also use from time to time.)  And why should they?  Most
of their customers don't seem to care all that much.  But then, most of Kluge's
customers don't care how stiff their keys are either.

I'd best stop or I'm going to end up writing my article on Action Power all over
again.



> Further if maple were actually demonstrably superior, one
> would think that one or some of the quality piano manufacturers who use
> Renner parts would request maple, if for no other reason than advertising.

The last time I checked, Steinway still did use maple hammershanks.  At least in
their NY built instruments.

Aside from S&S, and since the public has proven a willingness to pretty much buy
whatever is put out there, not that manufacturers really care.  Besides, in the
end we're all going to end up using plastic anyway.

Del