I've got a frame for a product that we make in house and need to modify the tooling to fir the redesign. First, it must be modeled and a flat pattern needs to be generated. The problem is, I can't model the internl rib in the box frame. Has anyone had to model something similar that I could look at? I've tried starting with a solid model, starting witht the flattened model, starting as a sheet metal part, etc.