Hi, everyday i'm working with Sheet Metal, maybe this instruction may help you.
make a sketch on Front Plane
Make rail sketch on Right Plane
select from Insert> Sheet Metal> Swept Flange. Swept Flange features only available in version 2012 onward.
To setup Swept Flange bending input, please follow below instruction. Please take note that different type on bending option (Bend Deduction, K-Factor, Band Table, Bend Allowance) will result with different unfold size, for this bending, i recommend to use K-Facktor
Done- If you want to view the unfold, follow below instruction. Happy Day