Plate Flexing

[Farrell]

I may not be understanding the situation clearly here, so please bear with 
me. If you lay the plate down on a flat table, is the plate flat or can you 
see that it is warped?

What do you mean that the nose bolts are neutral? I presume you mean that, 
with the plate bolts removed, the hitch pin edge of the plate is resting on 
the rim dowels (or at least some of them) and just touching the base of the 
nose bolts? With the plate bolts removed, is the plate perimeter resting on 
all the dowels, or is it up off the dowels in the bass/tenor? I'm 
envisioning that the plate rests on dowels in the treble area, the nose 
bolts everywhere, but is raised up above the dowels in the bass. If that is 
the case, then I should think you could just lower the nosebolts, maybe 
trim/lower a few of the low treble dowels a tad and be back in business.

How flat is that plate?

You need to hear from Del Fandrich or Ron Nossaman for a good opinion on the 
effect of added bridge height. I know one time I thought I needed to make 
one a little shorter than normal and they both advised against it - however, 
maybe a little added mass in that area is not such a detrimental thing.

Terry Farrell


> The problem is that the bridge is pretty level all the way across.  So
> if you lower the plate at the nose bolts (which actually isn't possible
> because the picture was taken with the nose bolts at neutral) you would
> have to lower the bridge, unless you built up the aliquots by a
> considerable amount.  The dowels are all cut pretty evenly around the
> perimeter.  The plate just warped.  My understanding is that during
> certain periods at Steinway, plate warping was more of a problem that at
> others.
>
> If you set the plate at neutral, as I mentioned earlier, that would
> force a fairly severe change in elevation, and mass, of the bridge from
> one end to the other.  What is the effect of that, I wonder.  The
> difference would be over 12 mm from low tenor to upper treble unless you
> could fool around with the plate and block at the treble end and raise
> that.  Then, of course, you start creating problems with string height
> and bore distance, etc., etc..  Maybe the correct answer in this case is
> jut to bend the sucker down and the hell with it.  I believe Shirley did
> make this one.
>
> David Love
> davidlovepianos@comcast.net
>
> -----Original Message-----
> From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org] On
> Behalf Of Farrell
> Sent: Friday, May 20, 2005 3:10 PM
> To: Pianotech
> Subject: Re: Plate Flexing
>
> How flat is the plate along the hitch pins? If that is fairly flat, then
> you
> should simply be able to adjust nose bolts to get the plate where you
> want
> it in that low tenor area. Is a string stretched across the bass notes a
>
> similar height above the bass bridge? If there is, is there any problem
> to
> simply lower nosebolts to position plate properly?
>
> Maybe someone tried to "tighten" the nose bolts in the past?  (i.e.:
> "what
> are those darn things for anyway?")
>
> Shirley the piano was not manufactured that way!!!!!!!!!!!
>
> Terry Farrell