AutoCAD Inventor :: Finding All Sheet Metal Parts In Assembly

I am creating a program to write out all the flat patterns of all sheet metal parts in an assy. I save it out as dxf. What I need is to totals of all the sheet metal parts across all sub assy’s etc in other words not “Structured” but “Parts Only” in Inventor BOM terms. All works fine but the only problem is that when a sub assy is a weldment or “inseparable”, it hides the parts inside it and “Parts only” BOM don’t make the internal parts of that sub available and the totals are not correct then. I need the totals because the idea is to write that into the file name including the thickness of the part.