I'd like to know too..
Helical fletching may be a good idea to control arrow flight on large shafts using broadheads but it's not necessary on smaller shafts used for target or 3D shooting. It may look cool but you get plenty of control with just an offset fletch and more speed too. As far as the fletch not contacting on both ends, that's a function of the shaft diameter and nothing else. The smaller the shaft, the less you can offset the fletch but it's kind of self correcting because you don't need as much with a skinny shaft. There's no way of knowing the angle of the fletch either and it really doesn't matter. Save yourself a lot of worry and just set up your jig with a straight clamp and get as much angle on the fletch as the shaft size will allow and they'll work fine. If the flight is lousy using this method, you need to set up your bow so that the arrow gets off to a better start and you don't have to use a lot of correction from the fletching.i spent a weak tweaking mine and i can finally fletch helical on smaller dia shafts, so i would say it may just need a little tweaking and experimenting.
zenith(sp) makes a conversion kit for bitz
Good response MGB. Neither the Uni or Super Uni arrows will go all the way onto the insert. Push them on only enough to seat them so they won't turn. The pin nock arrow should be inserted all the way into the insert. It can be a tight fit but will loosen up with use.1) You are correct about the uni-bushing over the pin with no nock. The "pin" is actually slightly tapered so you get a good friction fit, thus you should not expect the uni-bushing to completely cover the pin.
2) The adjustable plate will help you keep the centerline of the arrow in line with the centerline of the receiver no matter what the diameter of the arrow. The standard Bitz works fine with "medium" diameter hunting arrows, but when you get to the extremes, like 27/64th fatties or skinny target arrows (I've done ACG's 0.223"), you need the adjustable the plate to keep everything lined up.