Rib Curve Jig Pictures (Modified by Kent Swafford)

[Absolute Piano]

Hi All,

Thanks for all the input. Here are some pictures of the adjustable rib  
curving jig. It is fairly basic. There are two runners for the router  
attached to a U bolt. The U bolt is is tensioned by a turnbuckle  
forcing the runners into a curve. I have two capstans underneath the  
middle of the runners for fine adjustments and to support the weight of  
the router. There is also a clamping system to hold the rib in place. I  
only crown the top four spruce ribs and this method gives me a much  
better curve and parallel sides than my old method of using a belt  
sander.

I always assumed that the 60' in the 60'circle that is always discussed  
as the template for piano soundboards was circumference =60'. So what  
is the60'? C, D or r?

Thanks, Jude

https://www.moypiano.com/ptg/files/attachments/7b/35/9d/91/ 
RibCurveJig1.jpg

https://www.moypiano.com/ptg/files/attachments/1d/65/ff/99/ 
RibCurveJig2.jpg

http://tinyurl.com/22dmp

http://tinyurl.com/2zra7