New Steinway D problem

[Delwin D Fandrich]

This is a multi-part message in MIME format.

---------------------- multipart/alternative attachment

  ----- Original Message -----=20
  From: Baldwin Yamaha Piano Centre=20
  To: pianotech@ptg.org=20
  Sent: September 07, 2002 3:07 PM
  Subject: Re: New Steinway D problem


  At 09:24 PM 9/7/02 +0200, you wrote:

    jolly roger wrote:=20

      Hi Ric,=20
                   It's a tension bar, help prevent the two struts =
pulling apart.  The beams under the board also have tension struts.  =
That's those thinner slats that go cross ways.=20
      Regards Roger=20
       =20
      =20

  Hi Ric,
              You got me, on the Bell 'thingee', I have heard it called =
a treble resonator, or just the bell.  Yet I have never heard a real =
satisfactory explanation of what is going on.
You mean the cast iron thing bolted to the inside of the inner rim? It, =
along with the long coupling bolt going up through the soundboard and =
the plate, mass-couples the plate hitchpin panel to the inner rim. It =
reduces the natural tendency of the plate hitchpin panel to vibrate =
overly much in response to the vibration of the  strings. Any vibrating =
in this portion of the plate will result in a substantial and noticeable =
energy loss--i.e., it reduces an already short sustain time through the =
treble region.=20

Remember the natural vibration damping characteristic of gray iron? This =
is just one portion of the plate where you can dramatically see this =
characteristic in action.=20

The bell and the coupling bolt are not structural in any way, take out =
the coupling bolt and you can generally hear the sustain time drop off.=20

Which brings up the question, "how tight is tight" on that bolt and nut? =
I don't know what the official answer is but I make them snug, plus one =
turn. It needs to be tight enough to efficiently couple the two together =
but not so tight as to affect bearing and/or break something.=20

Del

---------------------- multipart/alternative attachment
An HTML attachment was scrubbed...
URL: https://www.moypiano.com/ptg/pianotech.php/attachments/01/25/47/9f/attachment.htm

---------------------- multipart/alternative attachment--