Upright plate bolts

[Kevin E. Ramsey]

    Keith, since I seem to be the first to respond to this, let me be the
first to give you this warning:

    "Confucius say, "He who over-tightens nose bolts, is asking for
trouble.' "

    If I read your post correctly, those are indeed nose bolts. They are
designed to prevent the plate from deviating too far from their design
parameters. They should not be loose, but they definitely should not be
cranked down. To do so could cause failure of the plate.  And as my brother
the auto tech would say, it's good for the life of the instrument, once it
goes, that's it for the life of the instrument.  ( Substitute auto for
instrument, in his case.)
    So, don't go cranking those thingees down, just make sure they're not so
loose that the washer can be moved with your hand.
    You'll probably hear from more expert people on this list, I just wanted
to get this warning out to you as soon as I could.  Just snug 'em a little,
but don't crank down on 'em.
    By the way, how did you get to the screws behind the strings? Got the
strings off?


----- Original Message -----
From: "Keith Roberts" <kpiano@goldrush.com>
To: <pianotech@ptg.org>
Sent: Sunday, January 06, 2002 4:43 PM
Subject: Upright plate bolts


> I have a 1911 A. B. Cameron upright, (given to me). As part of my
continuing
> education  I am doing various projects that I get to see the immediate and
> long term effects of each project. I tightened up the plate bolts and
> screws, (the ones behind the strings were the loosest), and what a
> difference in the sound. The tubby sound all but dissapeared. However,
there
> is a stud that comes out of one of the back posts, through the sound board
> (not attached to), through the plate with a large square nut on it and no
> back up nut under the plate. This is located below the hitch pins for D5.
> There is also a screw that does the same thing on the post to the right
and
> is below the hitch pins of note B6. It appears to me that this might
affect
> the downbearing on the bridge and the tension of the soundboard. What is
the
> purpose of these, and how do I adjust them? Should I rely on my mechanics
> wrist and elbow function that tells me when it's tightened to the max
torque
> just before failure? Thank You in advance.
>
> Keith Roberts
> Associate PTG