S & S 'M' Hammer line

[Bill Ballard]

Sorry to weigh in so late in the week on this thread. I hope it is still
within your attention spans. The consensus as I read the posts is that
because engineering departments like to lay scales out based on straight
strike lines, that something must be wrong when we see a hammer line which
has been curved

On 5/19/97, Horace Greeley <hgreeley@leland.Stanford.EDU> wrote:
<<For a time after the publication of Ed McMorrow's fine work "The
Educated Piano", there was a great flurry of activity around folks
changing strike lines in a somewhat more arbitrary that educated way.>>

I've bent hammer lines numerous times, and in each situation, it's been to
"find the tone". In my experience there's nothing arbitrary about
relocating a strike point based on how it sounds.

On 5/19/97, Horace Greeley <hgreeley@leland.Stanford.EDU> wrote:
<<The problem, _I_ think came when a arbitrary number came to be set for
this length.  In a piano manufactured so perfectly as to "mirror" the
designer's intent, perhaps that approach might work.  In the real world of
piano making, things are not so reductively accurate; and one must rely on
one's experience.>>

I still don't know why this happens, but my only clue is that it's never
been a Yahama, and usually a Steinway. (Hint--variables in the assembly
process. "It's a feature, not a bug!") The NH Chapter had an engineer
(electronic, mind you, but with a *strong* hobby of player rebuilding and
researching acoustic bibliographies) who said that the correct strike
point, the one  for which the string from will have absorbed the maximum
energy from the hammer, is a function of Young's Modulus. Period.

Well, that may be. But, I usually start with the old hammer line's best
strike point on sample notes in the top two octaves, mark the spot on the
string with ball-point pen, and then hang my new guides at those marks.
(Here I employ a 1" square of plexiglass with a center pin leaving it
perfectly square so that, in gluing each guide, I can insure that a pencil
line centered on the molding is parallel to the plexiglass-mounted center,
which by definition will be square to the string plane

With the guides thus located at what the old hams said was the best spot
for the string and glued square to the string plane, I have much better
luck with strike lines, than with Steinway's "5-1/8" down the shank no
matter what" and vintage M&H's "locate #88 and 64, use the old #1 and
connect the dots". But there still comes the time when, the sound you want
just isn't coming out with hammer or string voicing. You start sliding the
action in and out, and the truth emerges. "Sound Rules."

On 5/20/97, DougHersh@aol.com wrote:
<<The trick was to use a glue that didn't stand out and look ugly amongst
the factory glue collars and to gently feather the curve shape and blend
it in as best as you could with the existing hammerline. Just move the
action in and out while striking those notes and listen for sustain and
clarity and if it needed it you will hear it.>>

What I've done is to lay mailing labels on the keybed just in front of the
keyframe in the regions containing weak notes, mark the shift in strike
point on the notes needing a change and look for neighboring notes which
didn't "notice the shift" (any many of them won't). Whatever the curve
needs to be, it will have definite anchor points at the notes which need
the shift. As for feathering this new line into the old one, take your
pick among the notes which don't notice the shift for a spot where the new
line leaves the old one.

Bending a strike line is not that rare a remedy. I don't consider it a any
more outrageous a departure than say, widening an octave because  it's the
only way to get a 5th to sound good. Sure, both of these are violations of
straight line principles, but out in the fifth row who's gonna know?

Bill Ballard RPT
NH Chapter

"No one builds the *perfect* piano, you can only remove the obstacles to
that perfection during the building."    ...........LaRoy Edwards