How to design a Forming Shoulder? at Solidworks?

Hello, thanks for read this! I have a little problems with the creation of 3D model with sheet metal of a Forming Shoulders on Solidworks; because, when a try to fold the part to make match with the tube, it's impossible for me!

Let me explain it.. the Part it's work!; i mean y send to cut on Plasma or WaterJet and the welding technician make the correct fold; but when i have to recreate that fold in solidworks for any presentation or Assembly Drawings i can't.

Thanks a lot.