Thanks to all for your suggestions. I saw the piano again today. The
keyboard is quite floppy. I had already Protek-ed the but centers
realizing that starting the hammer back from the string with far less
spring strength would mean its return was much more vulnerable to
butt center friction. I didn't notice anything out of hand before,
though. The jacks all made a common snap sound, hitting the butt
felts. Mark's suggestion about the catch (check) distance was good
although I was limited in the extent to which I could use it
successfully. The butt leathers are not dented (they're like slightly
flexible concrete). I already put in one beautiful butt (from a
complete set of Baldwins in '92--gorgeous buckskin), and that didn't
reliably improve it.
Patrick and Newton suggested non-existent upweight, Am I was leaning
there myself. In fact that's what I found. Downweights in the
mid-30s, and upweights in the single digits. So I rebalanced the #
from C#3 to F#5 (in the center section) for 25g upweight, with
quik-skrewed jiffy weights. The downweights are now only lifted up to
the mid-40s.
But I still needed to improve the jack's return on a very slow
release with a trace of lost motion, so that isn't entirely the
answer.
I feel as though I should beef up the hammer springs just slightly,
which will slightly (yeah, right....) increase the touchweights. So I
might be back where I started from, but I can't actually conclude
that until I reset one or two springs to surmise what the original
touchweights may have been.
My suspicion is that it's a particular balancing of hammerspring AND
jack spring AND lost motion AND back-leading, all other things being
reasonable as they now are. The teacher and her students are going to
try it for a week.
Measuring touchweights in verticals is near useless anyway, because
the particular touchweight you read, either up or down, is a function
of how far into the stroke you are and how much of the hammer's
weight is directly above the hammer center bearing its load. (As well
as a function of the usual gang of suspects.) Fortunately as the
jack's purchase on the under side of the butt decreases as the parts
cycle through, the weight of the hammer and but are being more and
more supported by the butt center.
So we'll see. Once again thanks for everyone's response. I thought I
was going to have to try switching temperaments or something.
Bill Ballard, RPT
NH Chapter PTG
".......true more in general than specifically"
...........Lenny Bruce, spoofing a radio discussion of the Hebrew
roots of Calypso music
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