Article From http://www.quicks.com , Last Updated Thursday March 27, 2008

Easton Tuning Technical Bulletins

The starting point to fine tuning. A highly recommended start to tuning you and your bow is the 'Easton Technical Bulletin', called" Arrow Tuning And Maintenance Guide" which covers a lot about setting up your bow and a basic tune ,further tuning and fine tuning. Also contains several helpful diagrams and selection charts.

Tuning With The Bare Shaft

Usually most archers tune a bare shaft with their fletched shafts to check the tune of tiller, nocking point, button , clearance etc. As the fletchings on the back of the shaft do weigh something it is a good idea to allow for this with a weight in place of the fletches for the bare shaft so that the bare shaft is nearer to the fletched in balance and overall weight. If you are using spin vanes this can easily be done just by wrapping them around the shaft, tight against the shaft, and holding them down with a tiny bit of tape.

Tuning Your Stabilisers 

The effect of rods and weights on the modern bow. A lot of things have been said about stabilisers. I think that a look at the history of the stabiliser is instructive. In the early days Earl Hoyt Junior and others such as Les Howis of UK's Marksman Bows put weights ,initially ,then rods and weights onto bows to iron out inconsistency in the shot. The early effects were dramatic on scores. Bows were strung with stretchy strings, rods were quite flexible and arrows quite slow and heavy. Today bows are stiff, arrows light and fast, strings have no "give", the energy of the shot is released into a very resonant system not unlike a tuning fork, the shock has to go somewhere. Bow and arrow and archer make a system. Especially if the bow arm is held firmly in place to make a strong shot. Each archer and the bow make a Unique system. The resonance of that system is Unique and the best stabilisers for damping the system are also singular to the Uniqueness of the system. Now to get the setup that makes your bow limbs close up and stop quickly and to maximise consistency you add rods of the stiffness and length and weight to work on your bow...you can see and feel if the stabilisers work well for you. It maybe that the least or the most expensive stabilisers are the best for you in this objective if they are the ones which fit your systems vibration requirements . On top of this a stiff rod enhances aiming so there are good reasons to look amongst these to start with. The new Multi-rod stabilisers with sliding weights may have an advantage as changing a rod or a weight will alter cast of the bow and balance of the bow. With a Tri-rod for instance you can alter the effective resonance of your system whilst keeping the balance and weight of the system the same. This can be done by sliding multiple weights along the rod until the dampening effect is tuned to your system, and tune your arrow flight from the bow so that tuning tests are optimised.

Tackle Tuning Tip; Fletching Size

When deciding on the size of fletchings you should use, a faster arrow can use a smaller fletch and remain stable. The slower arrow has to have a larger fletch (which makes it even slower). The optimum size keeps the arrow stable for the whole way to the longest distance you will have to shoot. So, a little experimentation is in order. The more stable the arrow is the better, as this will forgive your bad releases. The end result should be to use that size that maintains arrow speed long enough to reach the target (as small as you can get away with) but as large as you can get away with also( for the most forgiving shoot). No one said this was easy! On Carbon arrows for the 90m distance 1.75" is the usual choice being fast all the way but as big as will still maintain the speed down range. Most people find that the 1 9/16 " Spin-wing size is too small and a little too unpredictable. If your fletchings are too small then in a tail wind at the far end of the range, the arrow loses stability and the whole of the arrow back end will spiral as the shaft slows down. If this happens you should move up a size or angle your fletchings a little more. More next time.

Tuning Tip; Arrow Stiffness 

You can get away with an arrow that is too stiff when shooting for groups, but arrows are much less likely to group if they are too whippy. Arrows that are too stiff will land in the same place but off line to one side. Arrows that are not stiff enough will not group, so err on the side of stiffness if you are not sure . Providing you can get reasonable to good arrow clearance from the bow, arrow performance will be more consistent, and you can move you aim point or sight pin to compensate for the arrows flying to one side. On a compound in addition a heavier arrow will be more consistent than a light one, and often the higher power delivery of the compound will allow you to use a heavier arrow than you would have to choose with a recurve in order to get a good enough point of aim or sight mark. Compounds when shot with a release aid ,tend to tolerate a wider range of arrow spines than bows shot with a fingers loose as the horizontal "paradox" bend in the arrow on loose is eliminated almost completely.

Tuning Tip; If You are Using a Launcher Rest

On a Compound Bow with a release make sure that the arm supporting the arrow doesn't "give" under the weight of the shaft. Next make sure that the arrow is aligned with the center of the cam/wheel as it is in its power stroke, otherwise you will not get the best arrow flight.

Tuning Tip; When Choosing Arrow Length

With the use of lightweight carbon and carbon/composite shafts, it is less critical to get the shortest and therefore lightest shaft you can shoot as most archers now have plenty of sight mark. Instead think about having a shaft a little long so that perhaps 1.5" or more is beyond the arrow rest. The use of modern clickers such as the Cavalier one allows you to put the end of the arrow almost anywhere and still use a clicker. The arrow rests against the plunger button at a point near to the "node" point at the front end of the shaft; this will tend to minimise errors on loose as the node points of a vibrating shaft tend to stay nearly still compared to the very tip of a vibrating shaft. This is not a new idea but has been used successfully by some top shots.