Crown radius = how much arch in a segment ?

[Richard Moody]

Thank you Gerald!

    Since I had to put it into a spread sheet I thought I would post
the formula (very easy to read, thank you) in computer-speak. This
should paste directly in.

A8-((A8^2)-(B8/2)^2)^0.5

H = r-((r^2)-(s/2)^2)^0.5

H = height of arc
r = radius (A8)
s = chord or segment of circle (B8)

I suppose someone is wondering what height of the arc would be across
a segment  (chord) of 36 inches with 72 inch radius.... 2.863.    I
doubt if a sound board
would end up with that and then of course the string pressure tends to
compress it down. At 24 inches it is almost exactly 1 inch.   ---ric

----- Original Message -----
From: Garold Beyer <garbey@wingsisp.com>
To: <pianotech@ptg.org>
Sent: Tuesday, March 13, 2001 5:42 PM
Subject: Re: Crown radius = how much arch in a segment ?


h=r-the square root of (r squared-(c/2 squared)
h=height of arc, r= the radius in inches, c= chord length


> Subject: Re: Crown radius = how much arch in a segment ?
>
>