Sheet Metal Cone that Overlaps

I am trying to create a sheet metal cone that overlaps so that it can be riveted together.   I have watched all the posts about creating a cone....but I can't seem to get the cone to overlap.   The goal is to create the cone as a sheet metal part...add the holes for it to be riveted together and then flatten the part so it can be cut on a laser.   I have tried using spirals to create the cone and I can create a surface cone but not a sheet metal cone.  Any help would be appreciated.

SolidworksGeneral