I need to model a part that is made from a circular tube.  The end of the tube is machined with a complex pattern of barbs, hooks and tabs which are subsequently bent backwards, sort of like fishhooks or a palm tree. The problem is that I cannot figure out how to add sketched bends or angled flanges to circular edges.  If at all possible I want to model it via sheet metal methods so that I can collapse it back down for the machined pattern. 

Any ideas?