I would put as much helical as possible, making sure that the vane stays in full contact with the shaft. If the vane isn't fully in contact, after a few shots, the vanes will start comming off. I keep the rear magnet (closest to the nock reciever of fletcher) centered. By centered, I mean make sure the lines are in-line with each other. Then, I adjust the front one only. I read on archerytalk.com that this is good to do becuase it keeps the rear of the vane centered on the shaft so the vanes are perfectly spaced out. Don't know how true / acurate it is, but it seems to work good for me!!