[CAUT] Capstans to Tray

[David Love]

The most efficient procedure is as Jon Page outlined.  By first placing a
straightedge on the key end felt of each section you can level them before
you start.  Then using a Spurlock type jig, transfer the ht of each section
to the underlevers themselves which will give you very exact damper timing
with the key.  Once that is complete you can adjust the capstans to regulate
the damper timing with the pedal.  Afterwards you can regulate the sostenuto
tabs with shims to get them aligned with each other.  I can't imagine a more
efficient system to get the job done.  It won't really matter if the
capstans are on the lever or the tray.  I prefer the tray because it's a lot
easier to install and, as Jon mentioned, you don't need to worry about
stressing the flange center.  I suppose a periodic readjustment to
compensate for felt compaction at the damper might be necessary though I
think the change over time is negligible and might even coincide with the
compacting of the key and felt.  

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 1:06 PM
To: caut at ptg.org
Subject: [CAUT] Capstans to Tray

Thank you David. 

I've always had to think in a way that feels intuitively backwards to 
get this method right in my mind.  Seems like capstans would be best 
used for fine adjustment of dampers... if you were going to use them in 
the first place.  And I am still not convinced that timing could not be 
for all practical purposes just as easily and evenly set without 
capstans in the first place... but they claim this results in the most 
effective way of getting at both. 

The bit that makes perfect sense to me tho is the bit about changes in 
damper seating on strings with time.  Any change there will affect both 
timing and simultaneous tray lift, but adjustment of the capstan to 
compensate only fixes the tray lift.

The picture I supplied by the way is taken of a C7 which has been around 
for a while and serviced by any number of techs. If you notice the 
capstans are all over the place level wise and timing on this instrument 
is quite uneven.  The capstans effect timing in a kind of reverse 
sense... not directly but by letting the tech address tray problems 
alone when both tray and timing uneveness  need addressing.

Cheers
RicB


    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