Theorizing about the relationship between fletching location (forward/backward), spine, and paradox in an attempt to maximize vane clearance off the shelf.

This may be a multi-part question so please bear with me.

First question is: Is the initial string displacement off the fingers inboard (towards the face) or outboard (away from the face) in relation to the string's vertical centerline?

pop corn.

?????

“First question is: Is the initial string displacement off the fingers inboard (towards the face) or outboard (away from the face) in relation to the string's vertical centerline?”

You know… I’m sure the answer is well known, but it’s a very good question. I would be flipping a coin if I said one way or the other, so I won’t. I guess maybe that answer also depends on whether you’re not getting a clean loose or you’re plucking the string or not…

But I’m pretty sure that the ideal location for your fletching is as close to the nock as works for you.

as you release the string, it will push your fingers out of the way. Your fingers tips will not be strong enough to to force the string over. Now you could pull the string over to side just before unhooking your fingers also called plucking the string.

Hummmm!

What is the main question? The string rolls off your fingers away from.your face.

You Tube short video "Archers Paradox. To the Limit" should answer your questions.

That video doesn't have anything to do with the archers paradox, but sure does show the flexing of the arrow in different spines.

Bigdog 21 said: "Now you could pull the string over to side just before unhooking your fingers also called plucking the string."

Which 'side' do you mean?

Outward.. pretty hard to move it inbord into face

So thus far one poster says outward and another says outward due to a plucking release.

Corax: you're right, the answer should be well known!

Ok, let us assume a clean release: no plucking, no dragging fingers or collapse.

The question remains: does the string initially displace inward or outward immediately off the fingers?

With clean release hmmm. Possible String torque twisting the string as you draw would move it inboard. ?

String should move outboard with the paradox of the shaft As it trying to clear riser. and nock end flexing outboard.

Sorry meant inboard not out

By "face" do you mean the sight window?

Has to move toward the shooters face to get off the fingers.

MP

The fingers are displaced, not the string.

The shaft acts as a stabilizer and inhibits excess of side to side movement.

You have to remember that the focus is on pulling the shaft.

This video should answer your question. Mpdh is correct. As the string comes off your fingers it moves closer to the face.

https://www.youtube.com/watch?v=PdhzIKYq5z0

What Phil and Mpdh said, and why John Demmer has to put tape on his nose. :)

This is a good angle too:

I think Demmer could save some wear and tear on his beak just by turning his face more toward the target…

But the anchor he’s using does seem to work well enough for his purposes…. ;)

Something that video shows, is a concept I have advocated for a long time.

The arrow does not begin rotation, until well clear of the riser, and for that reason - shooting cock fletch orientation "IN" at 90 degrees to the strike plate is the absolute best for fletching clearance at pass.

Rick

I agree Rick. Jack Howard was a big supporter of that many years ago and I've found it works quite well.

Mpdh, Phil, George, 1buckurout and Rick-

Hopefully you're hooked; no slack on the line but the pole hasn't bent yet... :)

Assuming acceptable spine and release, is there a way to identify that perfect spot on the arrow to place the fletching to maximize strike plate clearance on that third (into the body, away from the strike plate) waggle of the nock end of the arrow?

Another question: As spine increases or decreases, is there a resulting change in magnitude and timing, or some combination of both, of that 1-2-3 oscillation of the nock end at release?

Maybe I am getting ahead of the topic, but you did mention fletching "location", so here's some input on that.

Naturally, the closer to the nock end the fletching is, the better chance of clearance during pass it will have.

But, if you get the fletching to close to the nock end, you then run into the possibility of your fingers contacting/slapping the fletching at loose.

To prevent that, I place the tail end of my flething 1/8" beyond the end of the longest finger from it's knuckle crease when in the extended position.

For me, that is my middle finger, and the fletching tail end is 1-1/4" from the throat of the nock, which accommodates both 3-under, and split finger style loose.

I shoot using a deep hook at those end knuckle creases, if that helps it make more sense.

Now, I know some will argue, that this can't happen, but it does for me, and doing it like I do solves the issue, and makes a noticeable difference in both my tuning, and shooting.

Rick

“ Another question: As spine increases or decreases, is there a resulting change in magnitude and timing, or some combination of both, of that 1-2-3 oscillation of the nock end at release?”

You’re thinking yourself in circles. (I do it all the time.)

Of course there is. That’s the whole point of measuring spine. Stiffer spine = lower deflection under the same load, and altering your dynamic spine is how you get to Just Right.

You can use stiffer shaft (static spine) with a heavier point or a “weaker” shaft with a lighter point, and as long as the deflection is the same, the two will shoot equally well.

As far as timing goes, seems that the smaller the deflection, the higher the frequency, and of course there is the modulus of elasticity, with carbon being the highest.

That’s a Plus for high FOC because the lighter, stiffer shaft will snap into line more quickly.

But speaking of thinking in circles, I’m gonna do a little of my own….

I agree 100% with Rick that an arrow is not going to start spinning until it’s clear of the bow. It’s not as if it’s going to spin while the nock is still on the string, right?

But that being the case, how is it that cock-feather in provides the most clearance at pass when it sure looks as if it would provide the least, just based on geometry. I’m not saying that it doesn’t. I’m just saying that I don’t understand how it does. ;)

J, I'm hooked, because I've always loved these type discussions.

I was evidently typing out my above reply as you were typing out yours. You just beat me to the punch a little. :-)

Rick

The closer the fletch is to the end of the arrow, within reason as Rick has pointed out, the farther it will be from the riser as it passes.. The center of the arrow is closest to the bow, the nock end is farthest away.

MP

Rick and MP,

I did not realize that fletching more rearward increased clearance at the pass. I always assumed the blah-blahers parroting the furthest back mantra did so merely for the 'longer lever' steering argument ala Ashby. That argument I've tested and discounted (for me).

Would you agree with Corax's statement about the frequency of oscillation increasing with decreasing spine (for a given bow and shooter)?

Down to the basement to fletch up a couple way back there and then to the range.

Thanks guys! :)

[[[ "But that being the case, how is it that cock-feather in provides the most clearance at pass when it sure looks as if it would provide the least, just based on geometry. I’m not saying that it doesn’t. I’m just saying that I don’t understand how it does. ;)" ]]]

Because, the cock fletch "in" only has to clear the strike plate area, which don't take much, so with properly tuned arrows, it clears with room to spare.

Whereas, with cock fletch out, the bottom hen fletch has to clear the width of the shelf, which on some bows is a lot.

May this picture will help with the explanation. Follow the lateral movement with your imagination.

Rick

And, to maybe help even more.

This picture has a grid of 0.25".

Should make it very clear to see, that with cock fletch "out", that bottom hen fletch has to move a lot more to get clear, than the cock fletch "in" does, and with cock fletch "in", that bottom hen fletch is starting out already close to clear, or near it.

Rick

Don’t know about frequency but I would think a stiffer shaft is going to straighten up sooner than a lower spine.

MP

"The fingers are displaced, not the string."

not the case...

Rick I shoot best with cock feather up. The graft you show should not happen on a arrow released. the paradox should have the feathers clearing the riser, your arrow fletching should be flexing away from riser. Hen feathers would pass Easier then a cock in .

Bigdog 21 - What the graft shows, is exactly what you just said.

Your look at the belly/string side of the bow. Not the point.

The yellow arrows show the direction of fletching movement away from the riser for both a left, and right hand bow.

The fletching moves away from the riser during the flex.

The graft shows, that with cock fletch in, the fletching clears the riser better, and it does in reality also. It has to. :-)

Rick

"The fingers are displaced, not the string."

not the case...

X2

Might be a little of both sometimes, but always mainly/mostly the string.

It's called string roll for a reason. :-)

Rick

Ha didn't see the yellow arrows sorry.

With cock fletch in or out.The cock fletch or the hens need about equal movement to clear the strike plate from their respective positions. The shelf is the problem. With the cock fletch in any position other than straight in toward the riser the hen fletches have to move much farther out to clear the shelf. Wide shelves are a problem & should be narrowed or at least beveled. The shelf is part of the "riser" we are speaking of. The easiest solution is an arrow rest. >>>----> Ken

Did a head to head test of my 'normal' fletch with back of fletch 1.75" forward of nock throat and a test arrow with the back of fletch moved back to 1.25" forward of nock throat. Otherwise identical arrows.

There was no appreciable difference in clearance, sound or flight between the two with my Montana, which is cut to center. The further back fletched arrow seemed to perform better out of my Kodiak Magnum, which has a shelf at least 1/2" wider than the Montana and is cut to .125" past center. Will continue testing, but I can't go any further back with the fletching: my glommit flap was a hairsbreadth from contact with the back of the vane. Farkin' cold today...

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