Scaling questions

[Tom Rush]

I rarely experiment with scaling when restringing a piano.  There have
been times, though, when I measure the scale of an instrument and find
it to be so bizarre that it *couldn't* be the original, and the scale
is unavailable.  I am currently faced with just such a situation.

The few references I have read on scaling generally give the formulas,
and talk about a desired tension range of, say, 160-180 pounds.  And
this works ok for the most part.  But I have learned that trying to
stick to this tension in the tenor section results in using very heavy
wire, which, quite frankly, sounds like crap.

I checked a Steinway M in the shop last week, and calculated the tension
on the lowest wire to be in the area of 120-125 pounds, obviously out
of the "desired range".  None of my books refer to this lowering of
tension in this section (and Steve Fairchild's charts, in this month's
Journal, don't either).

How can I best determine the wire guage in this section of the piano?
Are there some "rules of thumb"?  Or is there a good book available
that can help me with this?

Any help would be greatly appreciated.
--
Tom Rush
tarush@chatt.mindspring.com