Virtual Capstan

[Bill Ballard]

At 8:54 AM +0200 6/20/03, Richard Brekne wrote:
>Any input or experimentation by yourself or anyone else is really 
>cool as well.
>Might be kinda neat if this is ended up a collective Pianotech invention for
>everyones use. That would really be a feather in our hat eh ?

>But again... I'd like to see any and all get in on
>the further development of the idea. We have a lot of good thinking heads here
>with lots of creativity. Between us...we can perhaps put out a solution that
>does all that we really need it to do (relative to touchweight adjustments and
>key leads reduction) for minimal cost and effort.

I don't need to invent. I think you're doing a good job at that (or 
at least applying existing technology in inventive ways). But I think 
it would be valuable for any prototype to be able to observe/study 
coupling among the action parts.

Coupling between the capstan and the wippen cushion. The brass 
capstan is already conductive. A single strand of copper wire across 
the cushion should be enough to signal when these bearing surfaces 
pull apart. It would be interesting to a conductive material which 
was soft and pliable like refrigerator door magnet strips. Otherwise 
my best bet for covering an area instead of a line, would be the sort 
of brass mesh which goes into water in-line filters, Say, on a 
washing machine in-let hose. A whole sheet of it.

The solenoid would be real useful, as well, in terms of an endless 
supply of consistently measured keystrokes.

Other places where I'd like to look for contact would be the key 
bottom and corresponding front rail felt punching during repetition. 
And of course the hammer tail and the check leather. (If the check 
needs to be so high, what does it mean that the hammer never 
checks........)

>The convex headed capstan also
>seemed usable... but had minimal affect... but at least you could regulate the
>darn thing easy enough.  Lots of dinking around.

There's got to be a movie script in there somewhere.

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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