I've got a Grayling Jig and clamp fletcher http://www.cabelas.com/products/Cpod0004544.jspand I wanted to know if I'm using this thing right. This jig has three "click in" positions for the feather/vanes but each position has a large area of play thatallows for different positioning. Is this because it's a cheap rig? I would think it would lock into a position without any variation. I also know if I flip the nock 180* the positions don't line up I would think they would be the same if the three positions were 120* apart. Right now I've only done my practice arrows and it's becoming more of an art than exact science to get the right spacing between feathers. I'd like to get more consistent before I attempt to do my hunting arrows. Also there seems to be a tightening screw at the base that has no real purpose, what is that for?