I'm not sure exactly what you are getting at. Are you talking about the offset or helical? If you are talking about how the offset should be lined up, it should split the center. Helical will wrap around and follow the contour of the shaft and is my personal preference for feathers as they have a natural helical to them.I know there are a number of ways but what works best? Center of feather on shaft center, front of feather started on shaft center, rear started on center? I'm fletching 2" Rayzr's on 30x's so feather to shaft contact is really an issue.