Tonebell

[Erwinspiano@aol.com]

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      Robin
      Excellent info. Also, the 6ft. 1905 AB Chase that we rebuilt this year 
had a bell as well. The piano, built like a tank, had no claims to any thing 
concerning the bell. If the bell is such an incredible tonal device certainly 
it would have had a more noticeable effect on tone which to my ear does not. It 
also torque's the rim which could force the rasten/board joint to rotate out 
ward and there by upwards also adds torque the board.
  Dale
Dale,
Not to make any new points as to what the tonebell nosebolt does, as I
have already done so, but a couple of interesting items.  Mehlin and
Sons uses the exact same nosebolt, or at least it appears so, in the
corresponding place on their larger grands and in the same manner.  The
plate, as others note, is substantially different than a that on a
Steinway suggesting some reason to question the observation that the
bolt "mass-couples" the rim to the plate.  Were this the case one would
think that the difference in plate and rim of Steinway and Mehlin would
suggest a different "mass-coupling".  Yet, the one seen in Mehlins are
virtually identical to those of Steinway and, indeed, to my eye, appear
to have been produced by the same factory.  Incidentally, the larger,
6'4" Mehlin grand is, to my ear, another one of the number of great,
unrecognized American pianos.  I have not seen the nosebolt of the
smaller c. 5 and 1/2 ft grand.
     Haynes uses a metallic nosebolt not at all similar to those used on
Steinway and Mehlin and attached passing similarly through the plate yet
attached not to the rim but to the bellyrail.   They use this even of
their 5' 7" piano.
     Finally, just yesterday I looked at an old Kimball  upright which
had a similar stiffener comprised of an, apparently cast,  metallic
strip, perhaps   an inch or so wide and rather thick,  and containing a
patent number,  which extended on the back side of the soundboard
downward from an attachment into the back of the piano where the
soundboard is glued in.  I would hazard a guess that this pieces passes
into the back here for a substantial distance.  It extends about eight
or so inches, according to a most cursory glance, downward from its
attachment into the back at the top of the board, and then supports a
nut on a bolt which passes transversely to it into a hole and through
the soundboard, and, presumably, into the plate.  .  I didn't take the
time to open the case and look at the fastening method to the plate but
assume it is similar to the bolt in the Steinway "bell".  I will see the
piano again in a few days and may have more observations.  Were one to
take the number and read the patent,  which I can provide I would almost
be willing to bet money that it will be seen in the description that the
device is simply to stabilize the plate, or, perhaps, allow a slight
adjustment to follow the moving board over time, their claims being
similar to Steinway in this regard.  No mention will be found of
"mass-coupling" the rim and plate.   I still can't imagine these types
of  nosebolts as having much effect on sustain unless they were  used to
compensate for downbearing changes.  Were the plate set correctly, the
bridge planed well, and the bearing acceptable, I don't believe it would
make a significant difference.
     However, as has been discussed here in great detail, the board in
this area may subsequently move, perhaps significantly affecting
downbearing.  These devices would then afford the technician the option
of carefully increasing the bearing locally while allowing avoidance of
the difficult, global approach of having to reset the plate or recap the
bridge.  Of course, this could be achieved in some systems, at least for
the rear bearing by changing the string rest or plate.
Regards, Robin Hufford

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