popsicle stick engineering

[RicB]

Hi Kent, others.

I'm glad you put this up Jon. I remember 6 years ago when you brought 
this idea to my attention off list. I still have all that exchange. Good 
stuff.  The idea of thinking about the whippen needing a <<required 
travel distance>> struck home a note back then.  I remember thinking 
immediately that in combination with this the capstan could be fixed and 
the adjustment between the cap/whip on the whippen.   That way the 
capstan could always be on the magic line and at the desired angle at 
half blow (assuming keys are at right heights).  Might be a bit 
difficult to contrive such an adjustment on the whippen... but if it was 
done that way and the capstans were accurately placed thus... then it 
would (me thinks) tend to inhibit some of the er.. more creative 
combinations of key dip / letoff / blow / one runs into.

    Since you've already determined your bore length and selected the
    knuckle radius and key dip, place your temp capstan at this location
    and depress the key. Is the jack clearance optimal? If the jack is
    buried into the stop felt the capstan has to move forwards. If not
    enough clearance, move the capstan back (not every balance rail is
    in the optimal position either). Locate the capstan for optimal
    regulation:  sufficient jack clearance effecting minimal after
    touch. Think of it as the wippen being moved through a  required
    distance and how where along the levers the lift is provided
    regulates that distance. Bore the holes at the derived angle.
    .... snip

    ....But you need to bear in mind present touchweight. Increasing
    touchweight bymoving the capstan away from the balance rail for
    regulation may be counter productive. I get the feeling I'm about to
    get into a circular predicament.

Agreed, yet it seems to me that once you've accepted the basic premise 
here, touchweight.. or rather the SW ratio is a given along with the 
capstan placement. Or said another way... turning around this last point 
you make... changing touchweight by moving the capstan (alone) may be 
counter productive (to regulation concerns).  Circular it is me thinks. 

    Jon Page

Like I said.  I try and first insure an optimal geometry to whatever 
changes I decide to make.  THEN I apply Stanwood to whatever 
resulting/existing ST ratio I end up with.

Cheers
RicB



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