Archers Paradox

I frequent another sight where there is all kinds of bow shooters. One of them is a wheel bow tuning guru, and those guys swear that a centershot wheel bow with a dropaway rest thst is shot with a relaese will make the arrow bend up and down instead of sideways!

Bisch

[longbow fanatic 1]

Where are the physics professors among our group to definitely answer this question?    

[longbow fanatic 1]

Originally posted by Bisch:
I frequent another sight where there is all kinds of bow shooters. One of them is a wheel bow tuning guru, and those guys swear that a centershot wheel bow with a dropaway rest thst is shot with a relaese will make the arrow bend up and down instead of sideways!

Bisch

Here is a video of exactly what Bisch said. You can see no archers paradox, but can absolutely see the arrow flex vertically on the compound bow. The traditional bow, however, you can see the archers paradox (whatever the heck that means now) clearly.

 

[dnovo]

Does it really matter if you hit what you're aiming at?
I know about archers paradox but don't care to argue the fine points as long as I can hit my target

[njloco]

Bladepeek,

I've done that already with my compound, it does still show the arrow flexing as it travels toward the target but, there is no side plate to bend around since it is being shot off of a drop away rest. The arrow also seems to straighten out or lessen it's flexing faster than my LB. Unfortunately I can't find the camera or the video, sorry, it was done at least 8 years ago.

[grouseshooter002]

Guys,
I thing that we are all correct to some extent and to me the person or persons that coined the phrase didn't use a dictionary to look up the meaning, but just needed a word to describe what he was aware of without any way to scientifically prove it.
Archers Paradox relates to all stick bows that are drawn and released with fingers period. Where the point is pointed has nothing to do with the actual phenomenon.

Rick

[Al Dean]

Finger release, no matter where you arrow is pointed, the string moves left and right after release.  Correct brace height is where when the arrow leaves the string it is in the correct position L/R for the arrow to flex properly around the bow.  You need correct brace along with spine.

[Ari_Bonn]

Most noticeable with say a bow with no shelf or a very small shelf.  Depending which side the arrows is on of course the example is a RH shooter.

When undrawn the entire arrows points to the far left but when fully drawn the arrow straighents out towards the target.

There are 2 "very important bends" that will decide where the arrows goes the first is where the shaft bends into the riser(thats where you have to be very careful not to shoot too underspined arrows because it could bend too much and get stuck behind the riser and break then drop)

It rebounds and goes around the riser. Between these 2 points is why we try to match the best spine for our bows so that the shafts bend the the perfect amount and to straight to the target in relation to what we saw at full draw.


Center shot recurves and longbows still follow the same principle however the paradox is less noticeable because less riser the arrows need to clear. However since the shelf is so deep what would be perfect for say a ASL would show weak for a center show. Thus you need more spine for a center shot. ( hope people understand what I mean there.)

[snag]

Originally posted by longbow fanatic 1:
 

Originally posted by Bisch:
I frequent another sight where there is all kinds of bow shooters. One of them is a wheel bow tuning guru, and those guys swear that a centershot wheel bow with a dropaway rest thst is shot with a relaese will make the arrow bend up and down instead of sideways!

Bisch

Here is a video of exactly what Bisch said. You can see no archers paradox, but can absolutely see the arrow flex vertically on the compound bow. The traditional bow, however, you can see the archers paradox (whatever the heck that means now) clearly.

     [/b]

It flexes up and down because of the slight vertical force coming from the string.

[crazynate]

I'm careful about what I see on you tube. There are lots of helpful videos and also a lot of Idiots who think they know everything. Best video I ever saw was on you tube and it was Byron furgeson explaining it. Doesn't get any better than that

[T Sunstone]

Originally posted by highlow:
I'm with Pavan on this. When I shoot, it looks to me that my arrow is pointing directly at the target, not to the left. So the argument that it's pointed left and then corrects to the right in order to hit the target doesn't hold up. If that were true, then all my shots would impact right.

To me, the so-called "archers paradox" speaks more to a properly tuned arrow being able to bend around the riser as it leaves the string and then re-bend to continue on a straight path to the target. The need to bend properly arises from the fact that the string returns to the center of the bow as opposed to following the arrow on its trajectory. An improperly spined arrow will not bend, or oscillate properly in order to achieve the desired clearance of the riser. Too stiff, arrow impacts one way-too weak and it impacts another.

I''m not a physicist or scientist in any shape or form so you can take my opinion for what it's worth.

This    

The Byron video was correct, but pay close attention to what was said.  Where those two points line up with that bent arrow that is the line of flight of that arrow.   My first target bow, a Black Widow, was not cut past center or negative of center.   It was a loaded target bow and I shot it with a Wilson Strap tab.  If the paradox was too bring that arrow whipping its way merrily along to the target and if if what some think is that the arrow comes entirely back in line with the path of the limb travel line, the arrow should have disappeared behind the bow.  With a peep sight on the string and a very good bow sight, there was no arrow that would fly properly that would shoot so far to the off that it would strike that far right.   If that were the case i would have had to drill holes in the riser to accommodate a sight pin, of course they were off to the left with all of the flyable arrows.

[Orion]

This is the most misunderstood and misused concept in archery.  Even worse that trying to describe bow length or draw length.

Missed a few posts, but to respond to you Hilow.  Nope.  It's not what you said. The arrow doesn't correct and go to the right, it bends around the riser to go straight, though it was pointing left of the riser before being drawn.

In relation to the bow and string, the arrow still points to the left on the bow, but in aiming it at the target, you move the bow to the right to align the arrow on the target. The arrow still has to bend around the riser and straighten out to hit the target.

If it bends too much, i.e., the spine is too soft, the arrow will impact to the right.  If it doesn't bend enough, i.e., spine too stiff, it will impact left of the target.  If it bends just right, it will hit the target.  

Grouseshooter, shooting with fingers or not has nothing to do with Archer's paradox.  It merely contributes to the flex of the arrow by adding a sideways occilation to the string.  Go back and read the original definitions. A paradox is a conundrum.  It's an observation that apparently defies explanation, i.e., why does an arrow seemingly pointed to the left when on the bow strike the target when commonsense, observation would suggest it should strike to the left.  That's the archer's paradox.  The answer to that paradox is, the arrow flexes around the bow to straighten itself out and strike the target.

[BAK]

Physics are physics, and you can't get past them.  If you induce thrust directly in line with the plane of the mass of the arrow there will be no flex.  Reality is getting that perfect a tune job is very very difficult.

It could be done with a mechanically released shaft and fully center shot bow, either compound or recurve, but I've never seen that level of perfection achieved.

[Orion]

BAK.  Of course there will be flex.  The physics principle in play here is "objects at rest tend to stay at rest".  When the bow string pushes the arrow from the rear, the arrow wants to stay at rest, but it can't.  It will be pushed forward.  In so doing, the shaft will flex, from the force applied to the rear of the arrow as it tries to overtake the front of the arrow, which doesn't want to move, regardless of the orientation of the string, even if it's in perfect alignment with the arrow.

Easton demonstrated this more than 20 years ago with high speed photography. On compound bows released with triggers on arrows that were perfectly centered on the string, the arrows flexed both side to side and up and down, i.e., fishtailed and porpoised. The amplitude of those movements is dictated by the spine of the arrow, the greater the spine, the less the flexing. Because most wheelie shooters shoot very high carbon spines, and their bows are centershot,  there isn't a lot of flexing, but they do flex and it is easily detected with high speed photography.  

Conversely, the less the spine, the greater the flexing, to the point of the arrow breaking if the spine is way too light. In fact, the myth that you can't/shouldn't shoot wood arrows out of compounds bows is based on that principle.  Folks thought, and some still do, that wood arrows aren't stiff enough to shoot in compound bows.  Some may not be, but an appropriately spined wood arrow will shoot out of a compound just as well as any other material.

Of course, now we're getting way off the track.

We had the argument here a few years ago that the arrow bends outside of the bow string line at release because of the fingers rolling the string.  With a 96 pound bow that cannot be very much.   i told them it first bends in, no one would believe me, but I have the Hill dvds and in slow speed it is obvious.  One fellow said fingers cause that.  One had access to a very high end camera, from a local college, they tested our bows. my longbows shot with a release all had the inward arrow flex which was obvious at slow speed.  It cannot be avoided with a bow that is outside of center.  The limbs drive forward the resistance of the arrow at that angle bends the arrow in and by the graces of paradox with the bow as a pivot and spring action of the shaft gets the opposite bend which gets it around the bow.  A lesser bend in and an even lesser bend out then the miny waggle to the target.  What we found even more interesting was that carbon arrows and aluminums have a waggle all of the way to the target that is greater and more obvious than my wood  arrows.   I do not know why that is, but my wood arrows settled in and flew without that waggle.   My hoyt target bow with its 15and something aluminums were amazing in flight, they vibrated all the way. I don't like to think about that rig when comparing arrows speeds, it was very hard to see the arrows fly out of it.  If one could get any hunting arrow out of a longbow going that fast, you would have something.

[Orion]

Sounds reasonable to me pavan.  I no longer have the Easton video.  We used it when I taught bowhunter education courses.  What I do remember is that the string imparted one to two lateral occillations to the back of the arrow before the arrow left the string.  

Given that the string would roll to the left (for a right handed shooter) at release, that would create an inward bend of the shaft initially.  And, the shaft bends back outward as it clears the riser if it's spined correctly.

Of course, that's why shooting form is also part of the tuning equation.  Some folks impart more lateral movement than others.  It's the combination of lateral movement at release and arrow spine that determines whether the arrow will clear the bow cleanly.

What we found is that it happens even with a mechanical release with a hill longbow, not a lot different, if at all, from the finger release.  Of course, my lightest longbow that I had at that time was a 72 pound Schulz.

[Orion]

Yep, an arrow has to flex.  Which way it initially flexes depends on how it's released and its orientation on the bow; how much it flexes depends on its spine, orientation on the bow, method of release, point weight, etc.

To stay on message, it's the flexing of the arrow that explains Archer's paradox. I.e. the paradox is the observation that the arrow flies to the target rather than veering off to the side as one would expect from the orientation of a nocked (or drawn) arrow on a less than centershot bow.

I'm not getting into to this except to say... 1. Read what Orion has written; 2, Paradox is not flexing, it's the difference between where the arrow is pointed at brace and where it hits.

Remember now... flexing/bending is not the paradox of the arrow.

Good luck fella's.  Enjoy.   8^)