Summary & Mystery was Flat Facts

[William R. Monroe]

Alan,

I, for one, would believe the pin turning theory is possible.  I do however
also accept (perhaps even more strongly) the concept that steel stretches,
and has no trouble stretching enough to make a piano go 50C flat in 10
years, as you say.  Consider a couple of points:

1.    How much does a string actually have to stretch - longitudinally - to
result in the lowering of pitch 50C or otherwise.  I'll be real scientific
here - not much.

2.    Strings do not stretch uniformly throughout their length.  There are
inevitably weak points in a segment of wire which will fatigue more quickly
than other areas even in an unstressed brand new string.  Further, strings
on the piano have been subjected to stress in a few areas in particular (up
by the tuning pin, pressure bar, etc.) when the piano was strung - likely
places for stretching/failure)

Sooooooooo, while I don't discount the pin movement theory, I think it is
well within reason to think that string stretching could account for the
whole tostada.  Probably more importantly, as with most things piano techy,
there are so many things at work here that we may or may not understand, it
can be futile to assign a singular cause for some phenomenon.

Respectfully,
William R. Monroe


---- Original Message ----- 
From: "Alan" <tune4u@earthlink.net>
To: "'Pianotech'" <pianotech@ptg.org>
Sent: Saturday, March 26, 2005 6:51 PM
Subject: Summary & Mystery was Flat Facts


Okay, here we go.

I was having a little fun being annonymous; y'all mostly knew who I was. And
I really don't think the question is naive, either. I think it's a darned
good one.

I've read the comments that have been thoughtfully posted, but I have a very
hard time believing that bridge grooves, string stretching, etc., will take
a piano 50 cents flat in 10 years--especially if it's an old beater that has
been crushing and stretching  for 75 years.

I agree with Sarah Fox; I think those pins are s-l-o-w-l-y turning;
unwinding, if you will.

It's the only explanation that, to me, could account for such huge changes.
If the strings were stretching, they'd be getting thin and I've measured
enough old strings to know that, except when abused, they don't change that
much. Soundboards could squash and split and be flatter over the years BUT
sooner or later all that stuff has to pretty well quit changing or the
bridge, for example, would be cut through into 89 little segments (I know,
some are close to that <G>).

The screw stringer question was a good one. Old hands, whatayathink?

As to Ron's comment on the Yamaha GH-1 low tenor: Install a DC with
undercover and it will--if it behaves at all like my experience with this
exact problem--produce a certifiable miracle. But, Ron, you didn't quite get
the stupid old saying correct. It should be: "There's no such thing as a
stupid question, just stupid people."

And Joe Goss, your comment "YGTBACMYGTBATB" triggered the following
enthusiastic response from me, to whit, "Huh?"

Alan R. Barnard
Salem, MO

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