I am designing a label/decal sticker on a cylindrical surface that has a curved outline.  It has to fit accurately on the cylindrical surface, so I need to figure out what the precise dimensions of the flat pattern are in order to get the label printed up.

sounds like it should be simple but solidworks can't seem to do this in a straightforward way!

(see attached example demonstrating an analogous scenario, this is not the actual part)

things I have tried:

1) sheet metal: if I create a cylindrical base flange and cut away my curvy shape, the flat pattern throws an error saying it cannot be un-bent.

2) flex tool - can get the pattern very close to flat by eyeballing, but it is impossible to make it truly flat.  not a great option IMO.

anyone else ever had this issue?