At 8:48 AM -0400 10/8/01, Farrell wrote:
>What an interesting concept! I am in NO way trying to put words in Del's
>mouth - I am very interested in hearing his reply to you question. I will
>speculate a bit though. I do not believe that in any way his comments
>suggest Precision Touchweight is not valid. I believe his comments are
>independent of Precision Touchweight, and he is simply stating that if an
>action/belly is precisely engineered AND manufactured, that BWs, WBW, FWs,
>other action geometry can be very predictable and as such, leading can
>indeed be very predictable.
Del's experience is simply different form David's
>I further suggest he is suggesting that a given
>quality piano can be manufactured in such a way to give FWs (not counting
>variances in action center friction) within a set range (and thus,
>predictable leading).
Del's operation is one of a couple (Ron Overs is in there too) whose
action assembly is based on enough engineering background and enough
control over the new parts going in so as to yield a predictable set
of FWs. Del, Ron and others succeed where the factories don't because
the same person who designs the action, executes it. (In factories,
there are a few degrees of separation between these two functions.)
>In practice, certainly the Precision Touchweight has the potential to yield
>more accurate results. But compared to the comparatively haphazard methods
>of action/belly manufacturing in many plants, Del's engineered method would
>yield much more accurate results than the 'individually weighing off keys' -
>and likely up to a standard acceptable to most of the piano-buying public -
>at a cost (just guessing here) of no more (maybe less?) than 'individually
>weighing off keys'.
I don't think either Del or Ron would be happy guaranteeing smooth
FWs in their assembly of an action, combined with an inner rim the
product of "the comparatively haphazard methods of action/belly
manufacturing in many plants". I'd guess that if they have control
over both the inner rim and the action, their FWs won't be erratic.
The basic principle is, if you can measure it, you can regulate it.
David has a comprehensive system (based on static measurements) which
applies itself beautifully to cleaning up "poorly hung" actions.
At 9:40 AM -0500 10/8/01, Ron Nossaman wrote:
>That's the whole problem. Keys are individually weighted to produce uniform
>static down weight. It's done as a "finishing" step to "overcome" the
>apparent irregularities in the action, but it doesn't. Weight distribution
>from key to key most likely isn't where the problem lies in the first
>place, so changes in weight distribution from key to key probably aren't
>going to fix it.
I assume you're talking about distortions of DWs due to friction.
>Pattern leading is a better approach because it's done as
>a foundation rather than a last ditch attempt at disguise. The leading
>pattern is, of course, established to accommodate anticipated action
>geometry and hammer weight graduation. With a reasonably competently
>designed pattern leading schedule, someone doing a "final" weigh off and
>finding wild discrepancies will know to look elsewhere than at the leading
>for the cause.
If in fact that kind of troubleshooting is part of that factory's
assembly schedule. More likely, not. So the choice of leading (either
fixed pattern, or individually set FWs) is irrelevant. With a pattern
leading, at least that portion of the lever train's inertia coming
from the leading will be held uniform (regardless of what kind of
mess may be sitting on top of the capstans). DW/UW will be reflective
the wide range of friction, leverage ratio and hammer weight from
note to note. With individually leaded keys (set for DW not BW, mind
you) the static measurement of DW will look good, but inertia will be
even more cock-eyed from note to note.
>That's why pattern leading is a better idea. It's a known weighting
>progression, and it helps to have SOMETHING reasonably dependable to work
>from.
I agree that it does a much better job of holding overall inertia so
a reasonable level of eveness than individual leading for DW. Inertia
is a far more critical quality to a pianist than simple DW.
At 8:55 AM -0700 10/8/01, Delwin D Fandrich wrote:
>To then call this process a feature is an indication of the contempt the
>manufacturer has for both the end user and the technician who ultimately
>will be called in to fix the mess.
At 8:30 PM -0400 10/7/01, A440A@AOL.COM wrote:
>Rejoice, production sloppiness is great news for the careful action
>rebuilder!
>Regards,
>Ed Foote RPT
Operators are standing by.
Bill Ballard RPT
NH Chapter, P.T.G.
"I go, two plus like, three is pretty much totally five. Whatever"
...........The new math
+++++++++++++++++++++
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