[CAUT] Capstans to Tray

[David Love]

I think I understand the confusion.  While the capstans are used to set the
lever height, they do not themselves have anything to do with damper timing
with respect to key lift.  It seems like a lot of extra work.  Just use the
Spurlock damper ht jig (or something similar) for setting the levers and
then adjust the capstans for the tray lift.  Eliminates a lot of useless
procedures.  

David Love
davidlovepianos at comcast.net 
www.davidlovepianos.com

-----Original Message-----
From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of RicB
Sent: Saturday, March 24, 2007 11:04 AM
To: caut at ptg.org
Subject: [CAUT] Capstans to Tray

Hi  Jon

I'm just reporting what they showed at the Acadamy.  I've been doing it 
that way ever since, and dont have any problems.


    IF the underlever capstan supports the damper for half blow
    then it is inhibiting the effectiveness of the damper, the full
    weight of
    the system won't be on the string.

    The underlever should be suspended by the wire, no contact with
    the tray or key end lifter felt.

Well of course the damper wire suspends the damper levers.  The tray is 
just shy of touching the caps in the end... not actually supporting 
them.  There  has to be a bit of play or the strings wouldnt be 
damped... Didnt think I had to spell things out quite so clearly..... 

But if you must...first the samples are set for half blow, then the 
capstans are leveled with a straight edge,  then set the tray so that it 
is just supporting the samples,  loosen all wire screws so that dampers 
are rough regulated for tray lift, then regulate a very slight bit of 
lost motion into the tray and fine regulate for simultaneous damper tray 
lift.

I will agree that any uneveness in keyend felt height is an issue in 
itself. But if you have a straight line there... and  a straight line of 
capstans to meet them... yes ?

The point here is, that once all is regulated so that both damper timing 
and tray lift are correct, then you dont want to go correcting any 
uneveness  in tray lift by adjusting the capstans. Why ??? for the same 
reason  you wouldnt add shims to the back of the key felt for said 
correction.

Any uneveness that develops in dampers over time because of felt 
compression etc effect both timing and tray lift.  But the correction 
for this is to loosen the wire screw and reset simultaneous lift that 
way. Turning the capstan may correct the tray lift.... but it wont 
effect the remaining change in timing. 

 From their grey book... the following order of the whole system is given.

1: Adjust the damper lever flange with shims so that its position over 
the key end felt is correct for both regular play and shift pedal play.
2: Adjust the guide rail bushings for smooth but firm play
3: Install the guide rail
4: Install Dampers themselves... i.e bending the wires for correct 
damper head angle and postion
5: Set the damper key lift to half blow (as per above description when 
capstans are installed)
6: Back off the tray and set tray lift using the wire screw.
7: Damper stop rail adjustment
8: Sosenuto adjustment
9: Damper pedal stop adjustment.
10: Damper pedal adjustment,  (where your lost motion comes in....)
11: Shift pedal adjustment
12 Striking point adjustment (cheek block stop screw)

Hope this makes things clearer....


    Regards,

    Jon Page