In Inventor, you'd make a 2D drawing and save it as a DXF file. But it won't run the CNC router by itself; for that you'd need to process it through a CAM program to generate G-code that the router's control software could understand. Probably your uncle has some software like that, otherwise you'd need to find some. Be careful about cutting carbon fiber composites (I'm assuming that's what you've got, not the loose mat which won't cut at all). The dust that's generated from doing that is very irritating.