broken plate

[Delwin D Fandrich]

----- Original Message -----
From: <Ojaituner2@aol.com>
To: <pianotech@ptg.org>
Sent: December 16, 2002 10:55 AM
Subject: broken plate


> Hello list,
> Well the unspeakable happened this weekend.
> While on my last tuning before buttoning up a restring on a George Steck
> baby, a huge bang and the realization that the plate had given way.
> The Capo on the bass side of the treble strut popped. woe is me.
> So while I proceed researching my journals and archives if any one has
> something to share with me about this and how to proceed it would be
greatly
> appreciated.
> Thankyou all,
> Dennis Ashly, RPT, Santa Barbara CA Chapter
> _______________________________________________


There was an article in the Journal some time back written by Jim Ellis that
you're going to want to read now. If memory serves it was in the issue that
focused on plates and that most folks put away unread due to lack of
interest.

Usually the cause of cracks like this go back to the original foundry pour.
I would guess the internal stresses that led to its ultimate failure are the
result of uneven cooling in a high-mass area of the plate. Not much you can
do to predict this sort of thing.

You're going to get all kinds of advice on how to fix the crack with the
"Lock-N-Stitch" process but it probably won't work with a crack in this
location. I'm assuming the crack is just next to the longitudinal strut. If
you can get in there with the things, go for it, it's a good system. But I'm
guessing clearance might be a problem.

Fortunately, this is also not a very highly stressed area of the plate. If
you can't get in there with the Lock-N-Stitch system it can probably be
welded by someone reasonable proficient and experienced with the welding of
cast gray iron. And, if he or she is good enough, it can probably be done
with the plate in the piano, though touching up the plate finish will be
some difficult.

Del