Rib Tapering

[Farrell]

You will get just such a question raised on All-Day-Wednesday in Chicago! And thanks for the damper reference. I will read up.

Terry Farrell
  
----- Original Message ----- 
From: "Delwin D Fandrich" <pianobuilders@olynet.com>
To: <pianotech@ptg.org>
Sent: Tuesday, June 04, 2002 12:12 AM
Subject: Re: Rib Tapering


> 
> ----- Original Message -----
> From: "Farrell" <mfarrel2@tampabay.rr.com>
> To: <pianotech@ptg.org>
> Sent: June 03, 2002 3:19 PM
> Subject: Rib Tapering
> 
> 
> > One of these 4 AM brain torture processes.
> >
> > Soundboard ribs generally are of more-or-less uniform dimensions for most
> of their length (I think some have a slight consistent taper from center).
> Towards the ends, they are sculpted out fairly abruptly - over just a couple
> inches of their length. Why is this?
> >
> > Is it because of the loading in the center of the board (more-or-less),
> along the bridge will tend to bend more so it is made stiffer in the center
> and less at the ends - if that were the case, wouldn't a consistent taper
> from center area to end be more appropriate? Or does the rib thin out fast
> to make the entire outer edge of the soundboard more flexible - much like a
> speaker where the cone is stiff and then it has a cloth or rubber surround
> at the edge?
> >
> > Is there any text that delves into rib dimension theory?
> 
> 
> 
> None that I am aware of, but we can talk about it in Chicago if you'd like.
> 
> Del
>