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Regulating Key Dip & Hammer Blow Distance
By Donald Dusenbury

Hi Steve,  Some starting point measurements are 10 mm (.390") on dip,
hammer blow 42 mm (1-5/8").  In my experience one can not expect piano
actions to have specific measurements -- capstans and action parts
change from instrument to instrument.  The after-touch (the relation
between let-off and hammer drop) can be changed by moving the blow
distance.

I have found the final test for good repetition is: the after-touch
starts 1/8" before final dip, drop just below letoff, letoff 1/6 from
string.  If aftertouch is low in the key stroke, decrease the blow
distance.  If the aftertouch is not sufficient, soft play and
backchecking will not take place.  The hammer tail should have a 2-1/2
radius for Steinways to backcheck on soft play.  Spring tension should
have a medium lift.

Look on the PTG web page and read the Pace articles.  A good place
to look for tools is

  Bill Spurlock <spurlock@spurlocktools.com>
  Spurlock Specialty Tools
  3574 Cantelow Rd
  Vacaville, CA 95688
  http://www.spurlocktools.com/

Good Luck
Don Dusenbury



(Message sent Fri, 23 Aug 2002 11:39:58 -0400 , from time zone -0400.)

Key Words in Subject:  Blow, Dip, Distance, Hammer, Key, Regulating