[CAUT] add capstans to tray?

[RicB]

Hi David Skolnik

No.. I meant what I meant.  But I see now what the confusion is all 
about.  Funny that none of the folks that regularly deal with Yamaha 
picked up on this.  A picture is worth a thousand words as they say... 
so I will include a picture of the Yamaha Damper Capstan system.

As you can see the capstans are lifted by the tray, but attached to the 
underside of the whippens.  And that I think should answer your 
questions and befunderments :)  I just noticed the picture Ron included 
in his response to Mark and see the function of that is entirely 
different.  I will think on the matter, but my first reaction is that 
one has no way of assuring precise damper timing for each key with that 
system outside of shimming the keyback felts... which is the whole point 
of the Yamaha capstans.  If the capstans on the tray in Rons picture are 
simply to make adjusting pedal lift of the dampers easier.... well I see 
the point but have no problem doing this the standard way myself.

Cheers
RicB

Its probably good that this confusion came up... so as to avoid techs 
thinking they can treat each system alike.


    RicB -
    We know you meant "damper lift", not "hammer lift".  Otherwise, I'll
    take two opportunities to prove my ignorance.  Or not.  I gotta tell
    you,  I'm reading this over and over and I isn't getting it.  It
    seems to be mixing up the key based damper lift with the sustain
    pedal lift.  Traditionally, you would set your sample damper heights
    to the key lift (1/3 to 1/2, no?), then set the other damper levers
    to the same height.  You would then shim or scrape to refine key
    lift, and the same for tray (sustain pedal) lift.  I would have
    thought that the capstans would address the latter step.  How do the
    capstans have anything to do with key lift?  And refining the damper
    lift by loosening the screw and readjusting the wire doesn't make
    sense.  Help me understand.

    David Skolnik


        At 03:27 PM 3/23/2007, you wrote:
         >Hi Mark...
         >
         >I cant speak for any article on the subject... but the Yamaha
         >Academy at Hamamatsu teaches that the reasons for capstans is to
         >assure that each hammer lifts at exactly half blow. Since at the
         >time they only had this feature on CF III's and I was at masters
         >level I only had this shown to me quickly and only then because I
         >was ahead of pace enough that they bothered to run me through it.
         >
         >One set samples for each section so that the damper lever
        started in
         >motion with the hammer at half blow for all samples.  Then one
         >leveled the capstans with a straight edge from below.  At that
        point
         >we were taught that these were not to be adjusted again unless it
         >was to re-level the entire set of capstans.
         >
         >They were NOT to be used to fine adjust damper lift from the
         >strings. This was to be done as normal by loosening the damper
        wire
         >screw and raising or lowering the damper as required.  They were
         >very adamant about that.
         >
         >Cheers
         >RicB

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