By looking at the markup in the picture, by "Beam" I think you mean this part of the fender in the video...

Interestingly enough, it is the curvature shadow from the surface I created in the last video!

This video shows a method I learned from a user here, years ago, to create those "Creases". (The user is gone. I think it was Lyes, or one of the other monsters who have left us!)