innovative upright action

[ANRPiano@AOL.COM]

I had a customer bring by the action of the piano he is refinishing.  He 
wanted me to replace the bridal straps, dampers, etc.  This action includes 
one very unique feature which I, in my limited experience, (15 years) do not 
remember seeing before except on a certain west coast action.  There is a 
spring connecting the jack and hammer butt to speed the return of the jack 
under the butt.  The spring is about the length and shape of the hammer 
return spring and it is connected to the butt by means of a silk thread 
attached behind the jack felt on the butt.  There is also a slot in the jack 
for the silk to pass through in order to connect to the spring.  At the bass 
of the jack is a spring tensioner.  The piano is a Chickering Bros. (the 
Chicago branch of the family) apparently from the early part of the century.

BTW from the best I could tell this system worked as I imagined it was 
intended to work.  The jack did reset before the hammer returned to a full 
rest.

Has anyone seen one of these before?  I have seen a number of Chickering 
Bros. pianos and they all seem to be well built, often with "unique" 
features.  It seems the experimentation bug was genetic.

Andrew Remillard