Fw: Patent Notice

[Bill Ballard]

Thank you, David, for a very clear statement of the patent issues 
here. (No, I haven't taken the time, as you did, to actually read the 
document.)

At 10:41 PM -0800 10/29/02, David Love wrote:
>But this discussion can also serve as a vehicle for differentiating between
>Stanwood methodology and Stanwood design.

Do I understand correctly that the former is that which he has placed 
in the public domain (and which is included in the PianoTek) kit), 
and the latter is a set of specifications for an individual action 
resulting from his current procedures and thinking, most of which 
would be on the other side of the proprietary line from the former?

At 10:41 PM -0800 10/29/02, David Love wrote:
>Some of the aspects of what I observe are
>the characteristics of "Stanwood design" are clearly neither new nor
>proprietary: the tendency toward high strike weight zones, the use of assist
>springs to reduce front weights, the placement key leads toward the balance
>rail.

(I'm not sure I can speak for David, but a fool rushes in.) By "the 
tendency toward high strike weight zones", do you mean his preference 
for heavier hammers and the possible influence this personal 
preference might have had on the location of SW guidelines? When a 
certified installer sends that action's raw specs for the action (new 
parts without correction), the installer can request that SWs stay 
within certain bounds (or even specify his own  at the outset). If 
the installer is generating his own design, based on the full breadth 
of David's procedures, he is in control of SWs. I wouldn't call 
David's inclination towards higher SWs (if that's what you had in 
mind), a necessary part of Stanwood design.

"The use of assist springs to reduce front weights"? You're probably 
referring to the long years in which these were installed in European 
(and some Asian) pianos. Was there ever a procedure for the setting 
of the strength of these springs, any more involved in than simply 
removing the weight of the rep? (ie. strengthen the spring until the 
rep hover in mid-swing?) That's kind of like inventing a rail with 88 
let-off buttons, choosing the button thickness to set the let-off in 
some general neighborhood well short of the string height (a generous 
safety factor of 1/4"), and as a finishing touch (taking advantage of 
the fact that these buttons turn), setting all screw eyes parallel to 
the rail.

Of course, I haven't done extensive studies of these actions 
(Steinways, Bosedorfers, Bechsteins, Schimmels, Kawais, and Baldwin 
Howards among them) to see whether the FWs accompanying these helper 
springs showed any sign of being set in anything more focused than 
just an across the board 10g reduction. (David has.)

Most of these factories no longer use the helper spring, and the 
standard explanation is that helper springs complicate deep fast 
repetition. This explanation as far as I've noticed is anecdotal, 
speculative, and not backed up by engineering studies. I'd be willing 
to bet that the helper spring got dropped because the limited use 
which the factories were making of them didn't justify their extra 
cost to the manufacturing. I don't have the Renner USA booklet on the 
appropriate use and installation, but I remember it being vague on 
both mattes. Presumably Lloyd Meyer got the best of the Renner 
factory's wisdom on this style of rep when he engaged them to produce 
helper spring reps. I don't remember the booklet showing much sign of 
that wisdom. Renner of course was around for those long decades of 
intermittent factory use of these reps (and frequently supplied them 
to the factories).

To return to the let-off rail analogy, certainly if l-o rails had 
been on the scene (albeit, with their poorly understood use), someone 
who discovers that the buttons can be turned to set in a uniform 2mm 
escapement can't claim to have invented the rail and buttons. But by 
the same token, the rail and buttons in their current use would not 
be not much to take credit for, without the discovery of their true 
capability.

Finally, "the placement of key leads toward the balance rail" is 
certainly not appearing for the first time in David's work, nor am I 
aware that he has claimed so. This is a simple engineering issue, 
decided on considerations outside of David's methodology.

At 10:41 PM -0800 10/29/02, David Love wrote:
>I don't mean this as anything but a compliment, but I
>sometimes think that David Stanwood owes his career to the inability of
>manufacturers (read Steinway) to follow the original design.

As might anyone of us devoting a major chunk of heir career figuring 
out how to correct a badly hung action.

>Is that because they didn't have the information?  Or were they just 
>not paying
>attention.  It's something I'll have to look into...... someday.

I think this answer is unknowable for many reasons, and hence 
speculative. What can be read is the record of FWs left by each 
manufacturer in each piano. If all one knows about is DW (and maybe 
UW), one wouldn't be drawn into the study of FWs. Thank you David, 
for getting us started in exploring what of David's ideas may have 
already appeared in the collective thinking of piano technicians.

Bill Ballard RPT
NH Chapter, P.T.G.

"We mustn't underestimate our power of teamwork."
     ...........Bob Davis RPT, pianotech '97
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