Hello tempfhor,

You wouldn't want to put something similar to a rib on a shet metal 90 degree bend unless you plan to weld it on. For added strength simply "punch" a 90 degree angle cross-wise to the bend (shown in the hand sketch below). I'm not sure however, if SW has such a sheet metal specific command. They may have a "punch" command however that you may be able to use to achieve a similar result.

Good Luck!
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