RE Grand whippen retrofit

[Bdshull@AOL.COM]

Jack:

I have a piano in my shop now which came in with this pinned capstan setup.  
>From my perspective there are several ways you can go:

1.  Keep the design (and the original parts) - This allows original 
engineering, which should work fine as long as your replacement hammers are 
not too heavy.  But you have to mess with the rocker capstans (anyone who has 
tricks for these I'm all ears).

2.  Install new wippens from the Renner kit, and install capstans.  This 
gives you a chance to process action geometry and have a hand at design 
yourself.   Again, you will not want to get too heavy on the hammers, and 
before deciding you will want to play with the configurations.  Jim Coleman 
Sr. mentioned the superiority of the pinned capstan because of low friction - 
you will want to be sure the capstan/wippen foot contact point crosses the 
key balance bottom hole/wippen center line for minimum friction.   You will 
want to regulate out the samples and be sure that all the coincident arcs 
works at the jack/knuckle point also (hammercenter/wippen center line), and 
you will want to measure the keystick to obtain the best ratio.  I used old 
Yamaha grand keys from an ivorite replacement job, cut out the capstan 
section, trimmed the bottom and glued in place on the key after determining 
correct location.  (Get this right;  you don't want to go back and relocate 
later).

3.  The cheap retrofit:  do the same as above, but with original wippens.  
This is what I did on the grand in my shop.  Make your own sample wippen foot 
blocks, cut the bottom of an existing wippen flat, and work with your samples 
until it works, as in 2 above.  Renner USA sells several sizes of wippen feet 
- I think the longest is 21mm, which is what worked for me.    Again, don't 
use hammers that are too heavy - a great application for the Renner and Abel 
light varieties.

#3 is cheaper but timeconsuming;  doubly so if you boo-boo and have to fix 
your mistakes.  #2 is ideal - you end up with new action parts, an 
easy-to-regulate hammer line and a wealth of experience.  Someone will have 
to pay for the parts, of course....Hopefully the client will - it sounds like 
quite a piano.

Any other ideas out there?

Good Luck, and let us know how it goes!

Bill Shull
University of Redlands, La Sierra University
Loma Linda, CA

In a message dated 99-05-28 01:55:39 EDT, you write:

<< I have in my care a George Steck 8'-9'(?) grand with a very unusual 
 whippen/capstan configuration. Instead  of a cushion, the whippens are 
pinned 
 to a kind of sticker(flange?). One end of the sticker is pinned to the 
 whippen and the other is pinned to the capstan. (Thankfully, this end has a 
 set screw!) The capstan is the double screw type capstan accessible only 
with 
 an offset screwdriver.
 
 I don't relish the thought of loosening 88 set screws just to remove the 
 stack, nor do I look forward to regulating the hammer blow once I replace 
the 
 hammers.
 
 My question is this:	
 
 If I replace the odd whippens with conventional ones and replace the old 
 capstans with 1"(?) dowel capstans, am I asking for trouble with the action 
 geometry?
 
 Does anybody have any experience/suggestions for how to go about changing 
 them?
 
 Or is it better just to live with the old parts if they are still 
serviceable?
 
 Okay, okay, that's three questions, but you get the idea. 
 
 Thanks,		Jack Lofton, RPT	Seattle
  >>