'Grey Market' Yamahas- again

[Delwin D Fandrich]

Stephen Birkett wrote:

> Well..yes and no. Del's description of the process whereby cracks can form
> within a compression ridged area of sb is on the mark, and I think his
> comments were only meant to refer to such types of crack (in response to
> Jim's letter). The damaged fibres do not go away in this situation of
> course.
>
> But...cracks per se are not a symptom of anything necessarily even a
> problem. Cracks developing in an otherwise undamaged sb, in response to a
> drop in moisture levels, are not a sign of anything serious. In such
> situations they are only a cosmetic problem, and have no mechanical,
> acoustic or internal structural implications...unless of course they cause
> things to come loose.
>
> Stephen

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Sigh . . .

Once again it seems that we must go through this.  Perhaps in the pianos that
Stephen works on what he has to say about soundboard cracks may be true.  I have
no direct experience working with pianos built much before 1870 or so.  I have
no direct, personal knowledge of how those soundboards were crowned.  But, with
the typical soundboards found in the so-called "modern" piano -- those built
from approximately 1870 on using the industry-wide technique of
compression-crowning -- it is not.

In all pianos using compression-crowned soundboards the crack is a visible
symptom of compression damaged wood fibers.  Cracks do not develop in the middle
of a compression (or pressure) ridge unless the wood fiber is damaged.  This
being the case, the soundboard is not "otherwise undamaged."

Pianos using soundboards crowned by other means -- i.e., soundboards whose crown
is supported entirely by a curve cut into the ribs -- very rarely develop cracks
in any climate, so with these the whole issue becomes moot.

The pianos being discussed, however, -- the so-called 'grey market' Yamaha
pianos -- do use compression-crowned soundboards.  That is why the compression
ridges developed in the first place and that is why the cracks subsequently
developed.  That is also was why they came to be discussed on the list in the
first place.

Regards,

Del