Let me begin by stating the end goal, since I may be going about it entirely the wrong way. I'm trying to add a 3" wide flange around the perimeter of part. See the pdf sketch. I've gotten a small portion of the flange added surface extruding the trailing edge face; it's in yellow on the model. I think the correct way is to sweep along a 3D sketch with a guide curve. I've tried sweeping the flange sketch along the 3D sketch w/o a Guide Curve and the result isn't right. I would like the flange to remain mostly tangent to the wing tip (see pdf sketch), though exactly tangent isn't required. I guestimated a projected curve that is my tentative Guide Curve, but get a wavy and bad result when I sweep with it. If I'm on the right track, can someone point me in the right direction, or suggest a new route if I'm entirely wrong?