Sheet metal square to round

[Anonymous]

If I create a square to round,  that would have 4 different sides.  I can place rips exactly were I want the seams. Is there any way to make each side a solid body? I've been able to do this using the split tool. But it becomes very messy and difficult. 

[Anonymous]

if I make a square to round by thickening, a surface model.

how do I then add the chord lines to the flat pattern?

this is an example of what I need to send to my shop. I convert the chord lines to etch

for ease of fabrication.