We are trying to find a way to make rails from an imported surface. We normally use Rhino to do this, but we are just trying to streamline and keep everything within Solidworks. I have tried a few things, but cannot keep spending time on this; so I'm here. The surface will turn into the top surface of a total of 6 rails. I need to extend each of the corners on the surface so the angle cut is no longer there. Then I need to fill them in to make a solid. I attached an .igs file of the surface and a .dwg of what the end result will be. Let me know what can be done. Thanks.