Unusual rib structure?

[Delwin D Fandrich]

----- Original Message -----
From: "Greg Newell" <gnewell@ameritech.net>
To: "Pianotech" <pianotech@ptg.org>
Sent: May 08, 2003 9:20 PM
Subject: Re: Unusual rib structure?


Del,
         Do I take this to mean that there is no sudden taper 4-6" from the
end of each rib? How thin is the gradual taper you speak of by the time it
reaches the end? Do you bring the rib all the way into the rim or does it
stop before the rim? Or do you still use the cutouts but leave a gap for
free movement?

------------------------------
That is correct. There is no sudden taper. We do generally inset the ribs
to notches in the inner rim (or bellyrail or cutoff bar) but only because
it's easier to align for gluing that way. We make the end thin enough so
that it doesn't really contribute all that much stiffness to the assembly.
The end of the rib usually ends up about 4 mm thick where (and if) the rib
overlaps the inner rim. On a production piano (where permanent jigs and
fixtures would be used for alignment) I prefer to terminate the ribs about
10 mm inside the inner rim for at least the half of the rib set.

Del