# spin wing angle problem



## jhinaz (Mar 1, 2003)

I use the 1 3/4" spin wings and I put them on straight. If you put them on at a 1 or 2 degree positive off-set it will increase the amount of drag.....which will cause them to hit "lower" at the longer distances. - John


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## monty53 (Jun 19, 2002)

You do not need to fletch them with any angle, fletch them straight. They have enough curl in them for a high spin.


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## ScarletArrows (May 25, 2007)

monty53 said:


> You do not need to fletch them with any angle, fletch them straight. They have enough curl in them for a high spin.


2nd that...Only been using spinnies for a couple weeks now and straight is definately better than anything else...helps with clearance too.


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## ScarletArrows (May 25, 2007)

damn edit function has been changed...

If you want increased drag go to another color....In my poll thread it appears everyone majority use white...yellow and blue are popular as well. I am damn tempted to try yellow....just waiting to rip up the whites I have on my Nano's right now.


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## benyamin (May 17, 2009)

ScarletArrows said:


> damn edit function has been changed...
> 
> If you want increased drag go to another color....In my poll thread it appears everyone majority use white...yellow and blue are popular as well. I am damn tempted to try yellow....just waiting to rip up the whites I have on my Nano's right now.


thanks everyone for helping me.According to your answers I think its better to fletch it straight unless there is a benefit in increasing drag that I dont know.
It raised another question to me that is there any benefit in drag force or we should bring it to the minimum?
Also talking about vane colors,whats the difference between them and how should I know which one is better for me?

many many thanks for your help:smile::smile::smile:


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## Poindexter (Jul 5, 2009)

First post after some lurking.

May I inquire why different colors of vane (spinwings or other) should give different drag or spin? This seems pretty contraintuitive to me.

I agree that my FITA gooroo, Judy Schaaf, said that the reason for the goofy shape of spinwings was so that they impart spin without angle on the shaft, thus further reducing drag.

This was in about 1992. Fifteen years later and spinwings are still the mutha for ya?

Aloha,

Poinz


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## VinZ (Apr 30, 2007)

Welcome and Congratulations on your first post Poindexter.


> May I inquire why different colors of vane (spinwings or other) should give different drag or spin? This seems pretty contraintuitive to me.


Rick McKinney did a great job of answering that in this post: http://www.archerytalk.com/vb/showthread.php?t=813260&


> First are the colors. White is the softest which allows for more forgiveness if the vane hits the rest or plunger. Yellow is next, then red, blue and finally black is the stiffest.


Does that answer your question?


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## Progen (Mar 17, 2006)

Poindexter said:


> ...
> May I inquire why different colors of vane (spinwings or other) should give different drag or spin? This seems pretty contraintuitive to me. ...


Just in case this needs to be said again, despite their varying stiffness, all of them have produce the SAME drag regardless of colour.


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## engtee (Oct 2, 2003)

Progen,
I have to disagree with your reasoning. If they are different stiffness, it stands to reason that the softest ones, being pulled through the air by a point that is 100 or more times their weight will move and alter shape more than those that are stiffer. In other words, those that are soft will open up more than those that are stiff, using the same arrow length and weight, and shot with the same poundage. To my way of thinking, that should mean that the stiffest will impart greater spin and therefore, more drag.


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## Progen (Mar 17, 2006)

Was merely paraphrasing what's on the Spinwing literature at the back of each pack, engtee. Take a read there.

ps. My apologies if I recalled wrongly but I think I didn't.


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## gig'em 99 (Feb 1, 2008)

Its been a while since I took physics, but drag is a function of surface area. If your spin wing is 1 3/4", regardless of color, the surface area is the same, therefore the drag created by the the spin wing is the same. But all fletching do three things...1. Straighten the arrow flight. 2. Spin the arrow both combining to 3. Slow the arrow (which is what we normally call drag).

The different colors impact items 1 and 2 differently. The stiffer spin wings, put more energy into spinning the arrow. The flimsier ones put more into straightening the arrow and less into spinning the arrow. But they both slow the arrow by approximately the same amount if the spin wings are the same size.

The main difference is in the rate of spin. This must be matched to the speed and overall tune (spine both dynamic and static, pile weight, etc) of the arrow. Too high of a rate of spin for a slow arrow, actually destabilizes the arrow. Causing the the groups to open up at longer distances. It isn't so much that the spin wings stiffness "slowed the arrow down" per say, but it is that it spun the arrow too fast without straightening it enough. The physics that are imparted on a bullet are much the same. Certain barrell twist rates work better for certain loads and bullet weights. Too much twist will also destabilize a bullet, and too little not stabilze it enough.

Someone with a better background in physics...feel free to correct me, but I believe this is generally accurate.


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## Poindexter (Jul 5, 2009)

Okay, thank you, gentlemen (and ladies, if any). I now understand how this could happen, if the different colors have different stiffnesses.

Gig, I have not shot an arrow in fifteen years, but during that time I took two _very_ stiff semesters of physics, and I can tell you that:
Aerodynamic drag is produced by three properties of the object under varying circumstances; surface area, and the combination of frontal area and aerodynamic coefficient. Aerodynamic coefficient is determined by the shape of the object. A 'barn door' object of 100 square inches frontal area would have many times more drag than an object of optimum (torpedo) shape of the same frontal area.

Thus I can see how the stiffness of the vane could affect the drag of the arrow in several ways. The more flexy vane might interfere with the bow less if it should touch, but it might distort under launch conditions to a less optimum shape and frontal area than the stiffer vane. This is of course speculation on my part - high speed photography, grouping, and drop would tell the tale. 

It certainly looks to me like spinwings would be much more problematic of bow clearance due to their shape, so I can see why (in the linked thread) they would be difficult to tune. Those of you _not_ using spinwings, what do you like, and why?

Aloha, 

Poinz


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## gig'em 99 (Feb 1, 2008)

Better to start a new thread on vanes, rather than hi-jack this one on spin wings.

Regarding bow clearance - If the arrow is tuned properly, the rear of the shaft will be bending away from the riser as it passes, although this isn't always a large distance, it will provide clearance. Also spin wings, if set up for the proper hand of the bow, actually curve away from the rest and plunger, which also adds to clearance. If the arrow departs the string at the proper point of its bending cycle, spin wings or not, you should generally be clear of the bow, with the exception of very tall fletching, where nock rotation will play a larger roll in clearance.

Spin wings actually work differently than normal fletching. The general science as presented by the spin wing manufacturers is that they don't produce drag, at least not like a standard vane or feather. If you were to look at an arrow from the front, with spin wings applied straight, you will see there is very little frontal surface area. So little infact, that this is why the manufacturers say that they don't create drag. Instead, the spinning is driven by vortices generated by the shape of the wing. It creates some sort of pressure differences in between the spin wings that make for more pressure on one side of the shaft than the other, which induces the spin. Vortex shedding is a more complicated process, that I don't even want to try to get into. But the general principle straightening vs spinning still works. The stiffer spin wings, create more turbulence in between the wings, which allows for faster spinning, than the less stiff spin wings, which open up more, and impart less spin.

In the end the "drag" as physics would define it, is the same. But the ratio of spin to straightening forces is different between the colors.


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## engtee (Oct 2, 2003)

Best bet to jump into the physics end of things is to look at Joe Tapley's findings.


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## gig'em 99 (Feb 1, 2008)

engtee said:


> Best bet to jump into the physics end of things is to look at Joe Tapley's findings.


For those of you who are interested...Joe Tapley's website is here:

http://www.tap46home.plus.com/mechanics/

Very interesting stuff under the arrow flight and tuning drop down menus.


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## Poindexter (Jul 5, 2009)

_Better to start a new thread on vanes, rather than hi-jack this one on spin wings._

I guess I did. Sorry, not intentional. I got enthusiastic. You guys and your friends seem to have very thoroughly researched subjects that were elements of folklore in the archery community around here. 

Aloha, 

Poinz


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## Barabus (May 26, 2009)

Hi my name's Simon a 58 year old returning archer from the UK. Very interesting thread and as a returning archer from a 12 year absence i have a few questions. Thanks Rick for all the information. 

Now when last i was shooting and i always shot SW's without any issues we used to top and tail them with a dob of glue, is the tape really any better, i'm sure many high scores were shot with glue (Jay Barrs 88 Olympics) (Steve Hallard UK) so is it just a fad? 

Also I have the Elite which are new to me on my ACE's and they seem fine but now i have X10's and with all the different info floating around am confused as to what to go for? Elite of Standard, 1 3/4" or 2". or in the case of Elites 2 3/16".

I dont want the expense of having to try too many differing types out and to be honest i'm not of a high enough standard to warrant it, i'd just like a straight answer as to which would "probably or possibly" be best.

Sorry to bring up an old thread and i wonder if Rick or any of the original posters will now contribute but it's new to me.

Cheers Si


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