I've been using Beiter Nocking Points (aka BNP)for some time and really like them. As with many things requiring installation that are mission-critical in archery, there is a few "Tricks" to getting good results like this:
First, study the Beiter Nocking Instructions - they are a good start. I use the Beiter Serving Tool (BST, aka "winder"), and the 9/32" BNPs with 8125 string material (8 loops = 16 strands), and for the serving I use currently is Halo in Lindsey's favorite color (red). Hint: when you measure anything on your bow be sure that no external forces are altering the bow - ie, leaning against a limb or a wall. And forgive me for lapsing into the first person here and there.
After I make a bowstring by serving the end loops, I measure the brace height, and set it with enough twists to get a 9" fistmele (doncha love pretentious terms?<G>) Fistmele sounds so much like the American slang, as in, "Hey, smartaleck, how would you like a knuckle sandwich?".
Having strung the bow, I draw it back and let down a number of times, shoot an arrow to insure the limbs are seated properly, then measure the height. I leave the bow strung overnight, and measure the height again in the morning. At that point I reckon it's done with the largest part of stretching and it's time to do the center serving. (I've tried hanging the bowstring from a rafter with 60 pounds of weight at the end, but didn't find it made a difference in stretching)
I temporarily serve the string with a braided serving material, VERY TIGHTLY. This compresses the strands of the string into one solid body which will be useful later, when you actually use the BNP. But for now, you want to use a Saunders metal nocking point on the serving and find the optimal nocking point for the brace height you want to use. The Saunders point is much easier to adjust up and down, of course, but it is heavy, and makes a big lump that the fingertab will drag against.
I USED to use an indelible marker (the kind meant to mark clothing) to put lines on the bowstring where the nock will go, but I now think it is better to use a measuring device that remains independent of the bow. The problem with marks is that it only works if your bowstring doesn't change as you serve, and I've found that even with due diligence, the string is going to turn as you serve, moving the marked position out of position.
Now I use a bowsquare to accurate measure the position of the nocking point relative to the plunger. I apply a post-it note to the square and draw on it an arrow to record precisely where the BOTTOM of the nocking point is (the point where the arrow actually goes), and at what brace height this is true.
Now, it's important that you recognize that if your fistmele changes, this point changes. If your tiller changes, this point changes. If the number of twists in your bowstring changes, this point changes. If you dial your poundage up or down, this point can change. And you don't want changes. At the end of this, I'll point out how to use this relationship of changes to your advantage.
So you have put the Saunders point on, and you start shooting at from 18 meters to 30 meters. If you can shoot good groups at 30, use 30, but otherwise use 18. You want a good group with fletched arrows, and you want to insure your arrows are not flying oddly (as if they were hitting your riser). At 18 meters I think that the bare shaft should ideally be from dead-center in the group to one or two rings to the left of the group at 9 o'clock for a right-hand archer (In other words, exactly the same height on the target). This indicates that the spine of the shaft is ever so slightly stiff, which statistically is a good thing.
IF the bare shaft hits above the group then you need to move the nocking point UP. If it is hitting below your group, you need to LOWER the nocking point. By the end of a few dozen arrows, this the bowstring has been "shot in" and should be done with all significant stretching, ready for the BNP.
Having found the proper nocking point and put measure to the bow square I then remove the Saunders point and carefully! unserve the center serving. I gently shave the serving with a sharp razor blade till it breaks and unravels, leaving the compressed bowstring unharmed.
Below the BNP: I start the permanent serving process below the nocking position, about the width of four fingers, and serve upwards towards where the BNP will be. I set the winder to a VERY TIGHT tension so that the serving is not likely to separate when I put another layer of serving on top later. To prevent the serving from moving up or down, I first unstring the bow so that I can carefully POKE the end of the serving THROUGH the bowstring strands without damaging them. Tease the strands apart just enough with something pointy but dull, like a bic pen. I try to get the middle of the string, 8 strands one side and 8 the other, and I tie a single overhand knot to keep the serving from falling out while I remount the bowstring on the bow. Anchoring the beginning end of the serving like this is one way to keep a serving from slipping up or down, later on.
To "serve in" the BNP you start away from the nock and work towards it, then through the notch in the shelf edge, up onto the shelf of the BNP, and then go away from it, which results in a double layer of the serving material on the string. This is good - it makes the area where your fingers hold the string to be much larger, and closer to the thickness of the BNP which reduces the "bump" caused under the fingers by the actual nocking point. The "bump" is much more pronounced with the Saunders Nocking Point, which I feel is bound to influence the release as well as wear out the smoothness of the finger tab. Two layers of serving material on the string area where the fingers make contact will make the serving to be almost equal to the plastic BNP height so the "bump" is much less pronounced.(see the photo at the top)
So back to actually serving: the point at which I put the Halo through the bowstring for the lower side of the BNP is at least THREE to FOUR FINGERS down from the lower end of the BNP. When I do the TOP side of the BNP I will put the Halo through about TWO FINGERS worth above the BNP for the same reason.
I poke the serving material through the bowstring then restring the bow. I lay the loose end under and over the tight overhand knot and wrap OVER it as I go up the bowstring. I insure that the loose end crosses over the twists of the bowstring to cause holding friction as it gets wrapped. I wrap 3 turns, and then pull it tight (cinch it up), push the turns DOWN the string, wrap 3 turns, repeat. After about 15 turns I snip the remaining part of the LOOSE end of the serving with scissors or razor blade. And continue, keeping the tension tight with the winder.
How tight? Well, how tight can you get it? Beiter warns in their docs not to make it too tight, that when its too tight the BNP will break. This is especially true for higher poundage bows, less of a concern for say, 30-35 pound bows. But we aren't yet to the BNP, so the more tension on this segment of bowstring only, the better. For the lower layer of the serving I serve as tight as I can. The precaution is to make sure you do NOT let the tension cause the bowstring itself to rotate, change in twists under the serving as you wrap it. Halo has a 90 pound test so you are not likely to break the thread. Beiter has recently come out with a winder with stainless steel parts instead of plastic, to support more tension and heavier use. I have yet to have either BCY#2 or Halo ever break because I was tugging too hard. As a result my serving will end up with around 45 revolutions per running inch of bowstring on the base layer. (!) The serving becomes much smoother as well. When using the winder I exert opposing force on the bowstring with my other hand, keeping it from responding and rotating.
In the region of the shelf or shoulder on the BNP where the serving gets laid down twice, I get 6 to 7 wraps going up and I use MUCH LESS tension on the shelf and on the trip back down over the first layer of serving - in fact I don't use the winder to perform the wraps in the shoulder, I do it free hand by pulling slack from the winder and using finger tension. (Kinda like when you FLOSS<G>). I am extremely careful to keep the BNP from twisting at all though, and this may be one reason they rarely break later on. When the serving reaches the inner lip of the shelf (closest to where the arrow's nock goes) the serving will reverse direction and start going back down the way it came, OVER the earlier course of serving wraps.
If, on the shelf, you are able to squeeze a turn of the top serving layer down INTO the lower layer then you didn't pull the lower layer tight enough, and you are leaving a little irregularity in the surface which I feel is undesirable. You can undo the wraps and try again till you are happy. Smooth is the goal, man, smooooooth. You can easily see in the picture at the top the angular notches where the thread passes into and out of the shelf through the rims to keep the bumps down.
After wrapping the shelf and about 1/2 inch down the string I then CAREFULLY check first the brace height to see if I've accidentally changed it, and then verify the nocking point height to insure that it unchanged. Be sure you compare the part of the BNP where the arrow goes, to the same position where the Saunders metal point was. As you go back down the string atop the first layer of the serving If you tug too hard on the top layer of the serving, the strand will push down between the first layer's wraps by spreading them apart. This in turn pushes the nocking point up, resulting in a bad change in the nocking height. So you want snug but not quite so tense as the first layer for most of the first layer's distance.
Serve downwards until about 1/2 inch above the beginning point, where you can then greatly increase the tension of the winder. If the strand pushes down between the first layer's strands in this area, that is ok because it doesn't affect the BNP. Continue down the bowstring as far as needed to insure that the point of contact between the archer's chest protector and the string will be served, be protected from excessive wear. This increases the life of the string. Ever notice how frazzled your string becomes there? Well, that's friction at work, and it could be messing with your accuracy.
Last chance to undo before you cut the serving thread: Check the nocking point's height once more. If it is off now, you can still undo the serving and redo it without wasting material. Once sure, you can finish this serving using the "inside turns" method, about 7 to 10 of them.
When it comes to finishing the serving i prefer the method where you undo wraps as you do wraps. I put SEVEN to TEN such wraps into the trick, and I have never had a bowstring serving come undone. Murray's Balbardie Archery Reference, on around page 15, has a good description for this.
Above the BNP: Repeat serving the top half of the nock, once again unstring the bow just long enough to poke the serving thread through the bowstring, then string the bow. For the top half, I start about two finger's width above the top edge of the BNP and serve it down and back up again, taking the serving high enough to leave an inch or two above the location of the kisser button (to be mounted last).
As you lay down the twists leading up to the top edge of the BNP, be sure that you don't put so many that the BNP end up bent or puckered. And again, once you have served the top shoulder of the BNP stop and verify the nocking height is right, and do so again right before you finish the top end of the serving - once you cut it you can't as easily adjust things without wasting all the serving you've done. And remember to prevent the bowstring from twisting in reaction to the winder's torque.
Try shooting groups and bare shafts, and decide whether you need to go to fine tuning of the Nocking Point height. If your bare shaft is low, then your nocking point is too high, etc.. If you don't want to re-serve it all, you have another solution.
I have never found any hard evidence that slight changes to the TILLER will cause adverse effects in and of itself. In fact, I've not seen anything that says that tiller has very much effect on anything of real importanct, by itself. But! changes in the tiller can have an effect on the nocking point! By small adjustments on the tiller you can have sufficient effects on the nocking point's height!
It's easy to test and see how this works. Hold the bow horizontally, resting on the stabilizer. Put the bow square on the string, with the ruled edge 1/4 inch away from the top of the plunger rim as though you were measuring BNP height or brace height.
Now, hold the riser firmly with one hand and either push down or pull up the tip of one limb causing a change in the tiller and watch the ruled edge of the bow square. See how it moves? See how that temporarily changes the nocking point height? It also changes the brace height, but only a very tiny amount that is of little consequence. By changing the tiller only a little bit, say, 1/16" to 1/8" of an inch, you can move the effective nocking point height enough in many cases to tune the BNP to just the right place so your bare shaft is amongst the fletched group! Before anyone jumps up with the opinion that the tiller controls whether the bow pulls up or down during the draw process, I'll admit to the possibility while stating that it's not been of consequence so far.
Hope this helps.