[pianotech] crown and radius

[Gene Nelson]

Try it with a piece of scrap wood. Make a rib
> about 18", or a half meter (Can I butcher linear measurement systems like 
> this without losing the logical point?), and put the high point of the 
> CONSTANT RADIUS crown as FAR OFF CENTER as you can. Feather it, as you do, 
> prop it up on identically sized blocks, and measure where the high point 
> of the crown is. It will be, I guarantee, unless you made something other 
> than a constant radius crown, in the center of the rib.

Thanks Ron,
I understand your explaination, combined with review of the chord and arc 
calculator given by David I am convinced that the technique used to cut my 
ribs must be something other than constant radius.
The high point has always been located where I specify.
More study required.
.
Gene