Spurlock shimming method.

[Delwin D Fandrich]

----- Original Message -----
From: "jolly roger" <baldyam@sk.sympatico.ca>
To: <pianotech@ptg.org>
Sent: May 07, 2001 10:30 AM
Subject: Re: Re: Spurlock shimming method.


> ...............now I'm jus a po ole
> >mud boy but dat says to me dat de "flying buttress", or the rim assembly,
> >certainly do play a hugely large part in the crowning of
> boards.........don't
> >it?
>
> Hi Jim,
>            Now this simple stubble jumper, from the flat land's got to
> tinking, Ouch! that hurts.  Now why do they notch the liners and rims on
> some pianers, and not on others. And the radius crown fans, also seem to
be
> fans of notched ribs.  MMMMMMM Can it be they double speak?????????  Nah,
> sound boards is not my area. I plain don't understand them. Seems to be a
> lot of experts with no real answers, but just some good impirical
> observations.

Because, back in the good old days when you and I were both young and animal
hide glue was the only stuff around and rib ends tended to come off they
piano makers decided to buy some insurance and 'clamp' the ends of the ribs
in place. Hence the notches. Nowadays it's pretty rare for a
rib-to-soundboard joint to come apart -- except at Baldwin -- so it is
unnecessary but still done out of habit and to satisfy the salesfolks who
can't get along without them. But they are not really necessary except where
the grain line of the soundboard panel approximately parallels the rim,
usually around the inside of the treble rim curve. Hence, the Walter where
the bottom 6 ribs 'float' as they should and the top 7 are inset to take
some stress off of the soundboard panel. Beside, most pianos can use the
extra soundboard stiffness up there.

Del