I am trying to extrude a square to round transition so that I can use it for a pattern to fabricate the fitting out of sheet metal. I have heard that you can draw the shape in 3D, explode it, and unfold it so that it can be used as a pattern. The rectanguler base is 12.125" x 5.125", the circular base is 8.25" and the fitting will be 12.25" in height. Can anyone tell me how to go about extruding this item so that it will show the proper number of say 10 to 15 degree bends? Please help.......