# New Hoyt Olympic Recurve



## Bob Furman (May 16, 2012)

I heard from a good source that Hoyt will be coming out with a new Olympic Recurve around November, has anyone heard anything about this or seen any prototypes?


Thanks,


Bob Furman


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## Aix (Oct 21, 2009)

I seemed to have noticed Elison was shooting a new (different) bow recently. Not sure if this is it or just another in his arsenal.


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## Bob Furman (May 16, 2012)

All I have seen Brady shoot is his HPX. I guess I will have to check and see. I was just curious....


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## Jim C (Oct 15, 2002)

I heard the same thing from good sources. No idea what it is
probably see it at Nationals if Brady or Jake have it. maybe a tamed down HPX?


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## Bean Burrito (Apr 20, 2011)

Probably not a new top end one, HPX/F7 seems to be it for the present. As far as lower end stuff goes, not sure.

And Brady has a few bows, and as far as I know they're all FRX/HPX and formula setups as far as regular shooting and practice goes. He may be testing prototype setups (not necessarily for Hoyt) but I doubt many people would be able to give you reliable information in that regard.


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## Viper1 (Aug 21, 2003)

Bob -

From experience - don't bother wasting your time or money. There really hasn't been any earth shattering changes in recurve design or performance in decades. On the plus side, thanks to the "gotta have the latest and greatest" crowd, a lot of last year's obsolete stuff can be had on the used market for 1/2 the price. 

Viper1 out.


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## Matt Z (Jul 22, 2003)

Jim C said:


> maybe a tamed down HPX?


Wouldn't that be a RX? 

I had a good conversation with Jim at the last shoot regarding the HPX and wanted to get his thoughts as I've been wanting to get a new bow in the near future. Being that it has less deflex than the RX, I was concerned with long term comfort vs. speed gain. Also, I was wondering on how harsh the shot reaction was compared to typical riser design. I still can't get the image of Brady constantly tightening stuff on his bow at the London test event.

At this point, I'm leaning toward just getting a RX, preferably used, but will be interested to see what Hoyt comes out with next. Or if Sky's new prototype hits the market, I'd be interested.


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## limbwalker (Sep 26, 2003)

What Viper said. 

Companies like Hoyt operate on hype and marketing. They HAVE to come up with something "new" every year or two to keep the "buzz" going about their brand. I've seen it in golf for decades. Personally, it's a turn off to me, and a bit of an insult intellectually if you stop and think about it. I mean, really? A design that was "groundbreaking" or the "best ever" just a year ago is now obsolete? It begs the question, "just how dumb do they think we really are?"

John


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## ThomVis (Feb 21, 2012)

limbwalker said:


> It begs the question, "just how dumb do they think we really are?"


I can answer that one: They don't. They (the marketing guys) just know how to tickle the trend following mob that makes up 90+% of our consumer society. Trending "new" products is the way to keep the global economy rolling. (I'll end my rant here before we go completely off-topic)


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## Robert43 (Aug 2, 2004)

So true but I love these guys so I can get last years model for 1/2 price or less. If this didnt happen I wouldnt be able to do archery



Viper1 said:


> Bob -
> 
> From experience - don't bother wasting your time or money. There really hasn't been any earth shattering changes in recurve design or performance in decades. On the plus side, thanks to the "gotta have the latest and greatest" crowd, a lot of last year's obsolete stuff can be had on the used market for 1/2 the price.
> 
> Viper1 out.


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## benyamin (May 17, 2009)

limbwalker said:


> What Viper said.
> 
> Companies like Hoyt operate on hype and marketing. They HAVE to come up with something "new" every year or two to keep the "buzz" going about their brand. I've seen it in golf for decades. Personally, it's a turn off to me, and a bit of an insult intellectually if you stop and think about it. I mean, really? A design that was "groundbreaking" or the "best ever" just a year ago is now obsolete? It begs the question, "just how dumb do they think we really are?"
> 
> John


do you have any idea why arrow manufacturers like easton dont follow this policy.x10 has been eastons best recurve arrow for many years and they dont seem to be willing to introduce a new model at least in the near future.


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## gairsz (Mar 6, 2008)

Matt Z said:


> At this point, I'm leaning toward just getting a RX, preferably used


Matt has a green 27' formula with medium 42# f3 limbs. This was a free usat bow that Matt won two years ago and only shot one round with in in Vegas before he switched to win&win. This bow has never seen the light of day and is like brand new. Let me know if you would be interested. Any one else as well.

Gary


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## fader (May 17, 2010)

benyamin said:


> do you have any idea why arrow manufacturers like easton dont follow this policy.x10 has been eastons best recurve arrow for many years and they dont seem to be willing to introduce a new model at least in the near future.


I'll take a crack at this one. Arrows need replacing more often then limbs and risers. Arrows break and get lost and we need new ones every time we change limbs or draw weight. Unlike limbs and risers which would last for the lifetime of the user if we had no reason to get new ones.


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## TheAncientOne (Feb 14, 2007)

Viper1 said:


> Bob -
> 
> From experience - don't bother wasting your time or money. There really hasn't been any earth shattering changes in recurve design or performance in decades. On the plus side, thanks to the "gotta have the latest and greatest" crowd, a lot of last year's obsolete stuff can be had on the used market for 1/2 the price.
> 
> Viper1 out.


I agree with Viper1, I've bought and sold several risers used for 1/3 to 1/2 of what they went for new. This way I was able to try several before I committed to something. I was able to resell them for what I paid for them with nothing out of pocket. (I am sorry that I sold my AeroTec though). I currently shoot a Hoyt Helix but one of my go-to bows is a Hoyt GM TD-4. If I had to choose a new bow today it would be a GMX with Sky or Border limbs. 

I would only buy one of the new Formula's if I could get it for a good price. This way I could resell it if I didn't like it.

TAO


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## Jim C (Oct 15, 2002)

fader said:


> I'll take a crack at this one. Arrows need replacing more often then limbs and risers. Arrows break and get lost and we need new ones every time we change limbs or draw weight. Unlike limbs and risers which would last for the lifetime of the user if we had no reason to get new ones.


good explanation-arrows wear out far faster than bows. even if you don't lose them, or bust them in the bale, they wear out.


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## TheAncientOne (Feb 14, 2007)

limbwalker said:


> I mean, really? A design that was "groundbreaking" or the "best ever" just a year ago is now obsolete?
> 
> John


If that's the case, they should have a trade-in program like used cars.

TAO


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## lksseven (Mar 21, 2010)

limbwalker said:


> What Viper said.
> 
> Companies like Hoyt operate on hype and marketing. They HAVE to come up with something "new" every year or two to keep the "buzz" going about their brand. I've seen it in golf for decades. Personally, it's a turn off to me, and a bit of an insult intellectually if you stop and think about it. I mean, really? A design that was "groundbreaking" or the "best ever" just a year ago is now obsolete? It begs the question, "just how dumb do they think we really are?"
> 
> John


"...just how dumb do they think we really are?" Have you seen what's on TV lately? ukey:

Of course, almost everything is like that (cars, furniture, clothes, TV, cell phones!, etc). I'm glad the manufacturers put a lot of effort into trying to create broad interest in their products and increase their sales volumes and profits - it's the American way (or at least was for a long time). It creates/sustains jobs and income that is used to sustain a lot of other support businesses in all kinds of industries; it lowers pricing of new models, and keeps prices of used equipment down.

Intellectually, I also find the constant "hawking and touting 'latest and greatest'" to be tiresome (just like commercials on TV, or billboards). But I'm glad the manufacturers are doing it, and glad they're having success at it. 

Seems to me that more ire would be directed (without having enough data to really justify me spouting off about it) toward the price of X10 arrow shafts. The product has been around a long long time, and the premium price boat - to recapture upfront design/development/engineering and marketing costs - would seem to have long-since-sailed. Of course, the market dictates price points over time, and Easton is continuing to be rewarded handsomely for taking the risk to develop the X10 and doing it so well ... just as it should be.


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## PilotPhill (May 28, 2012)

Yep, I'd say Easton is doing pretty well. One thing that I think would help them a bit would be a page on their website explaining how to choose arrows. That way we ( people new to the sport ) could actually understand why we buy one arrow over the other.


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## limbwalker (Sep 26, 2003)

benyamin said:


> do you have any idea why arrow manufacturers like easton dont follow this policy.x10 has been eastons best recurve arrow for many years and they dont seem to be willing to introduce a new model at least in the near future.


Easy, because they haven't been challenged. 

Look, I'll be one of the first to admit that the barrel tapered arrow design is flat-out brilliant engineering. And virtually perfect for what a recurve archer needs.

It's no surprise to me that barrel-tapered shafts continue to dominate recurve archery because of their physical characteristics, while much headway has been made in compound archery with all-carbon parallel shafts (nano pro in particular). 

Until a significantly better recurve arrow hits the market, or an equal one at a lesser price-point, there is simply no reason for them to move whatsoever.

When you see new products come out all the time, that tells me that there really is NO product superiority in the marketplace for that particular item.

John


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## AngelRa (Nov 15, 2010)

I disagree about design been just to create hype. I work as an Engineer in the electronics industry, and the designs we put out today are better than last year. But nothing is perfect and that "perfect" new design will reveal its flaws and weaknesses with time and use, so a new model is always needed... It is the way things are to become and stay in the cutting edge of any technology.


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## limbwalker (Sep 26, 2003)

I have no problem with a new model coming out to resolve issues with previous models. That's helpful, and common sense. It's just the hype associated with the releases that bores me.


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## AngelRa (Nov 15, 2010)

That is the marketing department's fault.


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## PilotPhill (May 28, 2012)

That is a very good point. I never thought about it quite like that before!


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## Jim C (Oct 15, 2002)

its a fine line the companies walk

if you constantly release new risers or limbs the average archer is going to

1) get upset when he just bought what he thought was the top of the line and now he has an "obsolete"(LOL) riser

2) its hard to take seriously the marketing claim that the newest riser is the best when they already have a new prototype being tested. You ask them why they don't get all the bugs of the Mark I rather than getting some out with Mark II and others out with Mark III etc


on the other hand, if you don't modify or come out with new stuff you look static. I remember asking EH Jr why the conquest they were selling in 2000 was the same as the one in 94 or 95. He noted the Conquest was the best riser he could make and it still was several years later. that sort of honestly doesn't make for huge profits though

but the big makers have talented people working for them and when you put something on the market you get feedback and that leads to innovation


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## hwjchan (Oct 24, 2011)

Not to hijack the thread, but how exactly does the barreled shaft of an X10 perform better for recurve than the parallel shaft of Nanos? (I shoot Nano XRs, so it's personal interest.)


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## Joe T (Apr 5, 2003)

limbwalker said:


> Easy, because they haven't been challenged.
> 
> Look, I'll be one of the first to admit that the barrel tapered arrow design is flat-out brilliant engineering. And virtually perfect for what a recurve archer needs.
> 
> ...


Half agree John. Why is everyone a using 20 year old (hence presumably technically obsolete) arrow design. Answer is really control of the market. Similar situation to Microsoft -Windows. Everyone was still using Windows despite it being technically obsolete and with alternative far superior products being available (which had no chance of gaining a significant market share) purely because of the monopoly position of the market. At some point no doubt Easton will replace the X10 with a technically superior shaft but that will be a commercial decision not a technical one.



> Not to hijack the thread, but how exactly does the barreled shaft of an X10 perform better for recurve than the parallel shaft of Nanos? (I shoot Nano XRs, so it's personal interest.)


Barreling gives you a lighter shaft with similar strength/vibrational characteristics. Also because of the way arrows are stressed when shot (and hence the barreling geometry) you get some aerodynamic benefit from the shaft cross sectional shape compared with parallel shafts.


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## Bean Burrito (Apr 20, 2011)

Barrelling also shifts the nodes of the arrow further apart.

The X10 is still around because well... It's still the best. It's hard to make an arrow much better designed, or thinner than an X10 (or Nano Pro, even though the barrelling is an advantage in r ecurve). Arrows can be made thinner, but then you start getting other problems. You need to fit 3 vanes onto it. You need to securely and straightly attach a nock, and the nock has to be wide enough to accept the string anyway. Not to mention a thinner arrow would be even heavier, and need a heavier point to reach the same FOC- which is a problem when you consider the length of existing points, and that weight decreases quadratically as diameter reduces. Such an arrow would almost necessitate tungsten points, probably bulging a fair amount. It's high weight would even further reduce it's target market, allowing only large, strong shooters to reach longer distances.

The cost would also be prohibitive.

Personally, if I was to engineer the arrow I would use a carbon similar to what is used in the Nano Pro, in a smaller diameter, barrelled with thicker walls. Aluminium/carbon would be a no go, as weight would be even higher, and space is at a premium (for a given volume, carbon is stiffer than aluminium, and lighter). An insert style tungsten point which flares out to a similar diameter as the existing X10 points, and is slightly longer (more weight to reach the same FOC). The bulge points would also reduce target damage. I've done some calculations and from a wind drift perspective a bulge point is more sound than a longer, thinner exterior point. They aren't quite as good in terms of downrange velocity, but it's minor (and bulge points would far reduce point breakage). 7075 pins with an aerodynamic nock such as the G pin nock. Due to the small diameter, fitting offset vanes would be tricky and mylar vanes (also increasing FOC) would probably be the best choice.

Edit: Perhaps titanium pins, even 7075 pins wouldn't be particularly strong (the smaller diameter section)


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## limbwalker (Sep 26, 2003)

> that sort of honestly doesn't make for huge profits though


Uh huh. 



> but the big makers have talented people working for them and when you put something on the market you get feedback and that leads to innovation


Agreed. It is a balance every company has to try and achieve, I'm sure.

Jim, I'm sure it's pretty rare for a company to operate with the freedom that Earl Hoyt Jr. had with SKY. Therin lies the beauty in what he had, and many of us know this.

John


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## Vittorio (Jul 17, 2003)

Joe T said:


> Barreling gives you a lighter shaft with similar strength/vibrational characteristics. Also because of the way arrows are stressed when shot (and hence the barreling geometry) you get some aerodynamic benefit from the shaft cross sectional shape compared with parallel shafts.


You are right about the fact that barrelled shafts are lighter shaft comparing with stiffer cylindrical designs.
Presently only Easton and Sky art are making barreleld shafts, as it seems impossible to make barrelled design in full carbon shafts.
But, the advantage of barrel is to give a weaker spine under the fingers for recurves compared to a stiffer dynamic spine, that means a well proven more forgiving design that is winning almost everything since 1989 (in recurve).
Companies making full carbon arrows are recognizing the problem of giving a more forgiving arrow to recurve archers than a traditional constant spine design, and are since a couple of yeras developping "variable spine" cylindrical carbon arrows, that are imitating the reaction of a barrelled shaft when shot from fingers. But nothing commercially available has been seen on the market, yet. When these arrows will reach the market (2013?) probably Easton will be forced to present something more advanced than X10 (rumors say they have these new shafts done since 2007), that is a 1995 design, a we all will enjoy a lot of new threads on AT about new arrows ...


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## limbwalker (Sep 26, 2003)

> But nothing commercially available has been seen on the market, yet. When these arrows will reach the market (2013?) probably Easton will be forced to present something more advanced than X10 (rumors say they have these new shafts done since 2007), that is a 1995 design, a we all will enjoy a lot of new threads on AT about new arrows ...


I wonder how many folks are reading this, and how many times it will be referenced in just a few years... 

It's not too soon to declare this a prophetic statement, I don't think... 

John


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## Xander (Dec 4, 2003)

Vittorio said:


> You are right about the fact that barrelled shafts are lighter shaft comparing with stiffer cylindrical designs.
> Presently only Easton and Sky art are making barreleld shafts, as it seems impossible to make barrelled design in full carbon shafts.
> But, the advantage of barrel is to give a weaker spine under the fingers for recurves compared to a stiffer dynamic spine, that means a well proven more forgiving design that is winning almost everything since 1989 (in recurve).
> Companies making full carbon arrows are recognizing the problem of giving a more forgiving arrow to recurve archers than a traditional constant spine design, and are since a couple of yeras developping "variable spine" cylindrical carbon arrows, that are imitating the reaction of a barrelled shaft when shot from fingers. But nothing commercially available has been seen on the market, yet. When these arrows will reach the market (2013?) probably Easton will be forced to present something more advanced than X10 (rumors say they have these new shafts done since 2007), that is a 1995 design, a we all will enjoy a lot of new threads on AT about new arrows ...



Vittorio,

I've a question for you. If I'm right I saw, Michele shoot a CX nano pro last week @ the EC in Amsterdam, which is a straight carbon shaft. This is the opposite from what you state here, that a barrelled shaft for recurve is always better than a parralel shaft. What's the reason he shooting these nano's? (and if he was shooting the nano's which size and point weight?)

Grtz 

Xander


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## julle (Mar 1, 2009)

@ vittorio, you just saved me a few hundred euros, i was thinking of buying xr's but hearing this i think i'll stick with my aces for a while. is your son maybe testing these? Perhaps branded as nano pro's ?
@xander,he was shooting nano pro's but they obviously didn't work for him  didn't you notice the two sixes he shot in the finals .


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## lksseven (Mar 21, 2010)

julle said:


> @xander,he was shooting nano pro's but they obviously didn't work for him  didn't you notice the two sixes he shot in the finals .


I would suggest not being so quick to blame the arrows. I always find it more soothing to blame 6's and 5's on my college girlfriend from 35 years ago :teeth:


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## aaronthesun (Oct 13, 2011)

Not to threadjack either but another question about barreled vs parallel shafts. 

X10 protours were developed for compound shooters, how does the tapered front/parallel back compare with barreled shafts like regular X10s or parallel arrow shafts? Is there any advantage for compound shooters in the same way that a barreled shaft is more forgiving to recurvers?


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## limbwalker (Sep 26, 2003)

aaron, I suspect that many compound archers simply did not have a dynamically stiff enough arrow in the 380 X10. I know if I shot 60# a standard 380 X10 would not come close to being stiff enough for my needs. This is why most compound archers were trimming inches of shaft from the rear of X10's, then again why they just dispensed with the rear barreled section to accomodate the compounders who needed a stiffer arrow.

John


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## aaronthesun (Oct 13, 2011)

thanks John! 

I really enjoy discussions like these but all you guys in the FITA forum seem to like recurve more, and I do target compound. Glad to hear the input!


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## whiz-Oz (Jul 19, 2007)

Bean Burrito said:


> . I've done some calculations and from a wind drift perspective a bulge point is more sound than a longer, thinner exterior point.


You may wish to redo your calculations until you change your mind. This would be contrary to every other aerodynamic principle evident in all practical demonstrations of the science anywhere in the modern world. Arrows obey the same rules as everything else. 

The primary advantage of the barrelled shaft hasn't actually been mentioned yet. 
For the same weight and spine as parallel shafts, they have superior resistance to wind drift. 
If everything else is equal in the archers, the arrow which is affected least by the random forces of wind will be the closest to the middle. 
If your closest rival is using X10's, best you do too.


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## Joe T (Apr 5, 2003)

whiz-Oz said:


> The primary advantage of the barrelled shaft hasn't actually been mentioned yet.
> For the same weight and spine as parallel shafts, they have superior resistance to wind drift.


Actually it was mentioned as in:



> Also because of the way arrows are stressed when shot (and hence the barreling geometry) you get some aerodynamic benefit from the shaft cross sectional shape compared with parallel shafts.


Granted not described in much detail (mea culpa);

If you look at a parallel arrow shaft in terms of the drag area of a rectangle then barreling the shaft clearly reduces this cross sectional area - so less "wind drift" drag. Barreling also reduces shaft weight which again reduces wind drift (higher foc effect) as well as increasing arrow speed. 

There is an additional effect due to the way the shaft is stressed at launch (essentially under acceleration the the shaft Easton spine increases as you go from front to rear of the arrow). Some complication as regards finger release but overall the barreling shifts shaft area towards the nock - it moves the shaft drag center of pressure backwards, increasing the shaft fletching effect again increasing arrow forgiveness and reducing wind drift.


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## Bob Furman (May 16, 2012)

Funny, I thought I named this Topic "New Hoyt Olympic Recurve"? Strange how one topic morphs into something else.... 


Bob


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## Greysides (Jun 10, 2009)

Sure is Bob.

Now, what are you having for lunch?


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## Bean Burrito (Apr 20, 2011)

whiz-Oz said:


> You may wish to redo your calculations until you change your mind. This would be contrary to every other aerodynamic principle evident in all practical demonstrations of the science anywhere in the modern world. Arrows obey the same rules as everything else.


Are you sure about that? A bulge point is more efficient the wind. While the point is wider, it is also much shorter as volume increases quadratically with diameter.

Pretend we have two points, of rectangular cross section (cylinders), one which is 5mm wide, the other which flares out to 8mm. The weight inside the shaft (that doesn't matter in terms of wind) is equal. Let's say that each point must have 6 grams of weight excluding the section inside the shaft.

pi x 0.25^2 = 0.196cm^2
pi x 0.4^2 = 0.503cm^2

We'll assume steel of 7.85g/cm^3. So for a 6g point we'll need a 0.764 cm^3 exposed section.

0.764cm^3 / 0.196cm^2 = 3.898cm

So, the 5mm point needs to be 3.898cm long to achieve the 6g requirement

0.764cm^3 / 0.503cm^2 = 1.519cm

So, the 8mm point will be 1.519cm long

Now, to figure out the effect by wind we need to know cross sectional area. Obviously, the less area, the less wind drift.

5mm point is 0.5cm wide by 3.898cm long, so:

0.5 x 3.898 = 1.949cm^2

8mm point is 0.8cm by 1.519cm long, so:

0.8 x 1.519 = 1.215cm^2

Can we see that the larger point would have lower wind drift? Yes? Good. I can redo my calculations as many times as I want, and I could also run it through $20000 design software a few more times, but simple geometry is going to be the same over and over again.

Obviously the point would not need to flare quite that much, but some flare is better than none.

Want to know something else? the 5mm tip is 3.208 times longer than the 8mm tip. As you appear to be an engineer (seen as you know so much about aerodynamic principles) then you should realise that in an impact that is not completely square to the target butt (every single arrow impact in existence, ever) the 5mm point will apply more than 3 times MORE torque to the extremely thin section in the arrow. Remember X10 points bending? That's why.


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## Joe T (Apr 5, 2003)

Bob Furman said:


> Funny, I thought I named this Topic "New Hoyt Olympic Recurve"? Strange how one topic morphs into something else....
> 
> 
> Bob


Apologies for my contribution for that....


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## whiz-Oz (Jul 19, 2007)

Bean Burrito said:


> Are you sure about that?


Yes. When the data is finally public, you'll be sure too.


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## Bean Burrito (Apr 20, 2011)

whiz-Oz said:


> Yes. When the data is finally public, you'll be sure too.


I'm completely sure of simple geometry. Seen as you know so much about what you're talking about, tell me what's wrong with the simplified working shown above. There doesn't need to be testing and data- it's simple fact, and I'm not sure how you can't see that.


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## whiz-Oz (Jul 19, 2007)

You're totally ignoring something that you haven't considered. 
Start your research with turbulent and laminar flow. When you understand the transition and what makes it happen, consider the problem again with bulge points and various amounts of bulge.


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## Bean Burrito (Apr 20, 2011)

whiz-Oz said:


> You're totally ignoring something that you haven't considered.
> Start your research with turbulent and laminar flow. When you understand the transition and what makes it happen, consider the problem again with bulge points and various amounts of bulge.


Oh dear, you cited some big words you read on wikpedia. Seen as I'm only doing a masters in mechanical engineering, I have no idea what you're talking about.

The reynolds number of each point would be very low (1100 vs. 1740, while turbulent airflow cannot be sustained at all below 2040) and both would have laminar flow, and would be similarly efficient airflow wise. Anyway, you've used some terms you've found to support your argument, without actually checking whether they're correct or not. Guess what- it doesn't matter here. They'll both have laminar flow. 

Look, if you had read my post rather than heading off on this unsuccessful and meaningless tirade, you would have noticed the primary reason for the bulge point was to reduce the massive amount of stress at the interface of the shank of a point and the long tip. That alone is plenty enough to justify the bulge point. Sure, even if the larger point wasn't as good in the wind, that means nothing if the points bend or break every goddamned shot.

Perhaps you should be writing to Easton and CX's engineers telling them how stupid they are for choosing bulge points.


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## whiz-Oz (Jul 19, 2007)

You know, if someone was quietly insistent that I was incorrect and offered a vague starting point as to why, I'd be interested in why they said that I was wrong. 
You seem to have no concept of what a tirade is and also the secondary implications of transition points between laminar and turbulent flow, or what causes it, encourages it or discourages it. 
Oddly enough, you're one of the people on here who I'm interested in reading because you're one of the few people who have a quest for the truth, rather than a quest for magic. 
Quite often, you get it right and you write something that makes me think that more people should read it. 
Other times you get it wrong and draw conclusions based on limited data sets or in this case, weighing in on the side of performance versus longevity compromises. 
Educational qualifications don't impress me much. Practical application and consideration of problem solving and design does. If you were of the caliber of Mark Drela or Michael Selig with your knowledge of low Re, I'd be impressed. But you're not, so I sincerely hope that you leave your post here so that I can eventually come back and quote it. 

You're also making a big assumption that no arrow engineers know who I am, or what I'm talking about. 
At this point, you're either feeling supremely confident that I don't know what I'm talking about, or considering what it is that you're not aware of. 
Given time and the facilities, you'd quite likely discover it for yourself, but you'd be a bit further along than a masters.


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## rharper (Apr 30, 2012)

UH OH, it's a my arrow is bigger than yours contest.


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## limbwalker (Sep 26, 2003)

Actually, it's a P---ing contest between two guys that IMO either don't shoot enough or at a high enough level to realize that the effect of the wind on the archer themselves is so much more significant than the effect of the wind on the arrow, it's not really worth worrying about.

But I've learned that most mid-level archers will argue about equipment until they are blue in the face. Meanwhile, most top level archers realize that equipment actually plays a pretty small role in who wins or loses.

John


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## Bean Burrito (Apr 20, 2011)

limbwalker said:


> Actually, it's a P---ing contest between two guys that IMO either don't shoot enough or at a high enough level to realize that the effect of the wind on the archer themselves is so much more significant than the effect of the wind on the arrow, it's not really worth worrying about.
> 
> But I've learned that most mid-level archers will argue about equipment until they are blue in the face. Meanwhile, most top level archers realize that equipment actually plays a pretty small role in who wins or loses.
> 
> John


Am I a top level archer? Nope.

Did I start a pissing contest about equipment? Nope.

All I did was explain how I would design an arrow to supersede the X10 (and how difficult it would be). This guy decided to pick on a minor point of mine for no particular reason (and incorrectly). Yes- I know that the wind is more of a problem in regards to the least consistent part of the equation- the archer. As I have said more than once, the shorter bulge point would be to reduce forces on the shank/tip interface. With the scale of a point, wind is a very minor concern- hence why I only made it a minor point in choosing a bulge point. I only stated that a bulge point is more efficient in the wind because I knew some clown would tell me how crap a bulge point is in the wind and that it should be as thin as possible (I was correct in my assumption). While wind is a minor concern, points breaking in half a thousand dollar a dozen arrows would be. 

My argument was from an engineering perspective, as was my original post. One side may have been a pissing contest- but I backed up my statement with facts, principles and numbers. Would those numbers matter all that much in terms of an arrow travelling downrange? Nope, not really. But do they matter from an engineer's perspective? Yes.


----------



## ThomVis (Feb 21, 2012)

Bob Furman said:


> I heard from a good source that Hoyt will be coming out with a new Olympic Recurve around November, has anyone heard anything about this or seen any prototypes?


Time to put that good source under the interrogation spotlight, cause no-one here apparently seen anything about it.


----------



## Vittorio (Jul 17, 2003)

If i well remeber, Joe T long time ago (2003?) established that the exit angle of the arrow from the bow is much more influencing the amount of wind drift of the shaft than any other parameter. I have had hundreds of demonstrations of his theory, that was bring to the variable tuning solution (button spring tension different depending from cross wind direction). That angle has an effect that is probably thousand of times more influent on arrow grouping in the wind than the outside size and shape of the point of the arrow. 
I have never considered the point shape to be important in arrow flight apart from:
- how much the shape can increase the FOC
- how much the shape can decrease the probability of bent points
- how much the shape can allow the consistency and the vision of the point under the clicker. 

For sure, then the shape of the back of the arrow (size of the nock in relationship to size of the vanes, size and type of vanes, angle of vanes and so on ) hasalso thousand of times more effects on arrow flight than bulge or conic shape of a point. 
IMHO. 

Definitely, this topic is no more about Hoyt new possible bow ...


----------



## whiz-Oz (Jul 19, 2007)

Bean Burrito said:


> I only stated that a bulge point is more efficient in the wind because I knew some clown would tell me how crap a bulge point is in the wind and that it should be as thin as possible (I was correct in my assumption). While wind is a minor concern, points breaking in half a thousand dollar a dozen arrows would be.
> 
> My argument was from an engineering perspective, as was my original post. One side may have been a pissing contest- but I backed up my statement with facts, principles and numbers.



You don't have all the facts because if you did, you'd know you were wrong. 

I can offer you some more chances to dig the hole deeper for yourself if you like, but the options are yours. 
Consider if you will, you going even further off your nut and continuing to tell me I have no idea and your masters in engineering is all you need. 


What is more likely to be embarrassing in future? 
Being proven wrong, or being proven wrong after you steadfastly went through all your calculations and argued your point, even when I indicated to where you were not considering the full effects?

So, just a summary:
I've indicated where you are wrong. 
I've told you what to consider. 
I've inferred that arrow engineers already know this information. 
I've alluded to me letting you dig yourself in deeply. 

I think that you've had quite a reasonable amount of forewarning of what is going to happen here.
At this point, the more cautious might start wondering how they could extract themselves from this gracefully...


----------



## TheAncientOne (Feb 14, 2007)

whiz-Oz said:


> Yes. When the data is finally public, you'll be sure too.


whiz, you've alluded to secret knowledge across several threads in the past, when can we expect this information to become public? You seem to have a sore spot when others doubt your expertise, since you continue to hide your identity we have no way of knowing what that expertise might be.

TAO


----------



## whiz-Oz (Jul 19, 2007)

I can't actually be sure when it will all be public as it's not my data. 
It is kinda cheating when you're playing with a stacked deck, but it sure is fun.


----------



## TheAncientOne (Feb 14, 2007)

Bob Furman said:


> Funny, I thought I named this Topic "New Hoyt Olympic Recurve"? Strange how one topic morphs into something else....
> 
> 
> Bob


That's what I like about it, you never know where the thread is going to lead.

TAO


----------



## rharper (Apr 30, 2012)

whiz-Oz said:


> So, just a summary:
> My arrow is EXTREMELY larger than yours is!!!! HAHAHA


Your manners are extraordinary:thumbs_do


----------



## whiz-Oz (Jul 19, 2007)

rharper said:


> Your manners are extraordinary:thumbs_do


Your inability to accurately quote my post deems your opinion to be irrelevant.


----------



## hwjchan (Oct 24, 2011)

So... How about them Thunders? 

This topic has definitely drifted away from Hoyt, in fact, does Hoyt even make arrows?


----------



## maxpowerpc2000 (Apr 5, 2010)

i thought Easton own Hoyt. I could be wrong.


----------



## PilotPhill (May 28, 2012)

We should start an Archery Debating Team for these guys. Mabey they could have their own form too.


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## Robert43 (Aug 2, 2004)

maxpowerpc2000 said:


> i thought Easton own Hoyt. I could be wrong.


Very true for about 30 years now


----------



## TER (Jul 5, 2003)

Wow, I didn't look at this thread until just now because I was thinking, "Oh Hoyt, new risers every year that make last year's risers 'obsolete' marketing strategy"... I don't care about Hoyt because I dislike their NEW NEW NEW marketing strategy... but it turns out there's a bunch of interesting info and argument in this thread.


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## Bean Burrito (Apr 20, 2011)

Whiz- I don't even have my Masters yet, and even I can see you don't know what you're talking about.

While I wasn't aware of your post style in the past, several members have pointed out to me that you fancy yourself as a bigshot archery insider, and from the looks of it, an aerospace engineer as well. I've laid out my facts, figures and reasoning. All I've seen from you is a statement such as:

"Secret knowledge than only I'm allowed to know about cos I'm really good"

Essentially, I'm done arguing with you unless you can produce some kind of factual reasoning to back your statements up. All I've seen so far seems to be classified archery information only the most elite are privileged to know of. By the way, tell all your sources/engineering pals that I'm extremely impressed that they have special techniques to circumnavigate basic physics. 

By the way- what's wrong with a Masters degree in engineering? May I ask what qualifications you have that make you far more adept at engineering than well... An engineering degree? And no- secret insider archery industry information doesn't count.

If I'm such an idiot, then prove me wrong.


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## whiz-Oz (Jul 19, 2007)

I never actually said that you're an idiot. 
You're just wrong about bulged points being better for wind drift. 
My factual statements only apply to your flawed assumptions. 
Nothing is wrong with a masters degree in engineering. A degree is a nice thing to hang on the wall. It means that you can pass the requirements to get one. 
Being able to actually apply that knowledge once you have it is something else entirely. 
And we're not actually arguing. In fact, if you read back about this, I agree with a lot of what you write. Good job carrying the request for proof about spingwing claims too, by the way. 

My qualifications? 
Interesting. I got an A+ for Science in the 10th grade and finished my Intro to ELINT course exam in 94 seconds with 100 percent correct. I've shaken hands with Ross Perot, been on joint exercises with the SAS and was known to all Deputy Police Commissioners in Australia at one point. I've flown a Blackhawk helicopter, visited the NSA and I can type at 60 wpm. In April 2007 out of 3400 people, I was the only one to get Frank Abagnale, Jr's autograph. I once threw a bed of 20's on a dartboard with my eyes shut (with witnesses), loaded an SLR magazine with 20 rounds in 16 seconds by hand and flipped a coin ten times in a row, coming up heads every time. (Yes, it got checked.)
If people want to tell me stuff because I'm interested in it and my experience in many fields lets me understand it, that's a bonus. 

If you're so sure you're correct and that you can't possibly be wrong, you've got absolutely nothing to worry about and you can go off feeling secure that you've lost nothing. 

But you may be sure that in the scheme of things, all you'll probably personally have to do is go "Wow, how about that? THAT is what he was talking about." and get on with your life. There are other people who will be probably deleting entire webpages and hoping that nobody noticed.


----------



## Bean Burrito (Apr 20, 2011)

whiz-Oz said:


> My qualifications?
> Interesting. I got an A+ for Science in the 10th grade and finished my Intro to ELINT course exam in 94 seconds with 100 percent correct. I've shaken hands with Ross Perot, been on joint exercises with the SAS and was known to all Deputy Police Commissioners in Australia at one point. I've flown a Blackhawk helicopter, visited the NSA and I can type at 60 wpm. In April 2007 out of 3400 people, I was the only one to get Frank Abagnale, Jr's autograph. I once threw a bed of 20's on a dartboard with my eyes shut (with witnesses), loaded an SLR magazine with 20 rounds in 16 seconds by hand and flipped a coin ten times in a row, coming up heads every time. (Yes, it got checked.)
> If people want to tell me stuff because I'm interested in it and my experience in many fields lets me understand it, that's a bonus.


Not exactly sure what to say to this, except that you sound roughly like this:





"I won an egg and spoon race once"
"I drink a thousand cups of coffee a day"
"I know all the words to Candle In The Wind"
"My car can go 100 miles an hour"
"I got a B in GCSE French"


----------



## TheAncientOne (Feb 14, 2007)

whiz-Oz said:


> I never actually said that you're an idiot.
> You're just wrong about bulged points being better for wind drift.
> My factual statements only apply to your flawed assumptions.
> Nothing is wrong with a masters degree in engineering. A degree is a nice thing to hang on the wall. It means that you can pass the requirements to get one.
> ...


whiz-oz - professional gadfly

TAO


----------



## lksseven (Mar 21, 2010)

Andy,

I've met Frank Abagnale, too! (he lives in Tulsa now).

Not disputing anything you mentioned on your resume (I hope it's all true!), but I had to laugh while reading it (less than two miles from my birth hospital, by the way - I guess I've got some catching up to do) - it reads like that Dos Equix beer commercial about "the most interesting man in the world" (shown doing all manner of things James Bond fantastical, and the money line "I don't often drink beer, but when I do, I make sure it's a 'Dos Equis." You could do the Australian commercial for them!

http://en.wikipedia.org/wiki/The_Most_Interesting_Man_in_the_World


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## limbwalker (Sep 26, 2003)

> My qualifications?
> Interesting. I got an A+ for Science in the 10th grade and finished my Intro to ELINT course exam in 94 seconds with 100 percent correct. I've shaken hands with Ross Perot, been on joint exercises with the SAS and was known to all Deputy Police Commissioners in Australia at one point. I've flown a Blackhawk helicopter, visited the NSA and I can type at 60 wpm. In April 2007 out of 3400 people, I was the only one to get Frank Abagnale, Jr's autograph. I once threw a bed of 20's on a dartboard with my eyes shut (with witnesses), loaded an SLR magazine with 20 rounds in 16 seconds by hand and flipped a coin ten times in a row, coming up heads every time. (Yes, it got checked.)
> If people want to tell me stuff because I'm interested in it and my experience in many fields lets me understand it, that's a bonus.


A legendary AT post. Should get a sticky...


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## whiz-Oz (Jul 19, 2007)

lksseven said:


> Andy,
> 
> I've met Frank Abagnale, too! (he lives in Tulsa now).
> 
> Not disputing anything you mentioned on your resume (I hope it's all true!),


Some will require locating witnesses. The Docent of the national cryptological museum in 2000 will be the easiest. Just mention the Australian guy who had a piece of the purple machine at work. 
He'd remember that comment.


----------



## lksseven (Mar 21, 2010)

Andy,

Clever! My wife and I are heehawing over it. :cocktail:


----------



## limbwalker (Sep 26, 2003)

All I can say is "wow"...

Feel free to take that however you like.


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## TheAncientOne (Feb 14, 2007)

Reminds me a little of Davy Crockett:

"In one word I’m a screamer, and have got the roughest racking horse, the prettiest sister, the surest rifle and the ugliest dog in the district. I’m a leetle the savagest crittur you ever did see. My father can whip any man in Kentucky, and I can lick my father. I can outspeak any man on this floor, and give him two hours start. I can run faster, dive deeper, stay longer under, and come out drier, than any chap this side the big Swamp. I can outlook a panther and outstare a flash of lightning, tote a steamboat on my back and play at rough and tumble with a lion, and an occasional kick from a zebra."

TAO


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## TER (Jul 5, 2003)

This is one of the best threads ever.


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## Scott.Barrett (Oct 26, 2008)

whiz-Oz said:


> I never actually said that you're an idiot.
> You're just wrong about bulged points being better for wind drift.
> My factual statements only apply to your flawed assumptions.
> Nothing is wrong with a masters degree in engineering. A degree is a nice thing to hang on the wall. It means that you can pass the requirements to get one.
> ...



Most epic post on AT ever!!!! Says everything, yet says nothing....

...and the winner is: Bean Burrito!


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## whiz-Oz (Jul 19, 2007)

Scott.Barrett said:


> Most epic post on AT ever!!!! Says everything, yet says nothing....
> 
> ...and the winner is: Bean Burrito!


This just gets better and better. 

Anyone else like to jump in? 
Surely, you're all feeling pretty confident by now. 
I hope AT has some good backup going so this thread is always available.


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## Scott.Barrett (Oct 26, 2008)

whiz-Oz said:


> This just gets better and better.
> 
> Anyone else like to jump in?
> Surely, you're all feeling pretty confident by now.
> I hope AT has some good backup going so this thread is always available.


I hope so too....you haven't presented any actual proof of your opinion, so you're just blowing smoke until you do.


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## whiz-Oz (Jul 19, 2007)

So you've just taken sides because you like being on the side of an argument?
You must not be capable of actually figuring this out for yourself. 
If you were capable of it, you'd know that it was wrong, or at least you'd be investigating why I assert that it is. Or even better, you'd be investigating the areas of aerodynamics that Bean Burrito's calculations don't consider.

So I'm going to have to assume that you just like being on what you consider to be the winning team, based on the premise of a discussion that you don't understand and the assumption that one side is in a losing proposition.

You could have just sat back and waited to see what happened. 
I'm sure now that there are people doing just that, who will be happy that they kept their mouths shut.


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## Bean Burrito (Apr 20, 2011)

whiz-Oz said:


> So you've just taken sides because you like being on the side of an argument?
> You must not be capable of actually figuring this out for yourself.
> If you were capable of it, you'd know that it was wrong, or at least you'd be investigating why I assert that it is. Or even better, you'd be investigating the areas of aerodynamics that Bean Burrito's calculations don't consider.
> 
> ...


Enlighten me- what didn't I consider. I'm sure there's a myriad of things I didn't consider- the question is if any of them matter at all. I don't factor in the Coriolis effect, nor do I factor in the gravitational pull of Jupiter. But why should I?


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## whiz-Oz (Jul 19, 2007)

You should consider what I've already indicated. You should consider it because it's the difference between you being right about your assertions and being wrong.


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## Bean Burrito (Apr 20, 2011)

whiz-Oz said:


> You should consider what I've already indicated. You should consider it because it's the difference between you being right about your assertions and being wrong.


I have- I've given you facts, figures and calculations, of which I'm confident in. All you've produced is well... Nothing. You have an incredibly weak argument, if any


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## limbwalker (Sep 26, 2003)

Some people just can't stand the idea that they could actually be wrong, nearly as much as they hate the idea that nobody knows they are right! 

Give it a rest fellas. Nobody really cares.


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## Matt Z (Jul 22, 2003)

limbwalker said:


> Some people just can't stand the idea that they could actually be wrong, nearly as much as they hate the idea that nobody knows they are right!
> 
> Give it a rest fellas. Nobody really cares.


Agreed. The reality is 98% of the people reading your pissing match do not understand any of it. Use PM and save everyone the bickering...


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## Bean Burrito (Apr 20, 2011)

Matt Z said:


> Agreed. The reality is 98% of the people reading your pissing match do not understand any of it. Use PM and save everyone the bickering...


No need, I'm done with him.

At any rate, I intended to add a logical voice to the argument, which he lacked. Apologies if anyone was actually upset by this (and if you were, perhaps rethink your life. If two guys you've never met arguing on the internet is enough to upset you then something is very wrong with you)


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## ASP123 (Apr 24, 2010)

Maybe the two guys *arguing on the Internet* need a rethink too. 

That post above listing stuff is just a bit tragic.


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## Aix (Oct 21, 2009)

We should have to pay money to read this. I've killed a good 30 mins of work time today doing so. Made the afternoon coffee taste that much better.


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## whiz-Oz (Jul 19, 2007)

Bean Burrito said:


> No need, I'm done with him.


Ha. You might think so. 
We're just at the mercy of a third party. 

For those that got a laugh and know what is coming, I'm pleased to provide the entertainment. 
As for the people who have been so badly inconvenienced because they had to read through all of this.... voluntarily, I may add, or the ones that didn't understand it and then felt forced to comment on how it inconvenienced their day, just remember that you're on the Internet. The device that has the greatest accessable accumulation of knowledge ever, in the history of mankind. 
If you just spent time which you consider to be wasted, the only person you can possibly blame is yourself. 
So give yourself a quick slap over the ear and go off and improve yourselves.


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## fader (May 17, 2010)

View attachment 1379580


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## TER (Jul 5, 2003)

I have to agree with Whiz's last point here. It's a discussion forum. There is supposed to discussion/argument. And it's also just a really entertaining thread.


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## limbwalker (Sep 26, 2003)

Whiz, I started to read your last post.

But then I lost interest.


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## SHADOW-MKII (Feb 19, 2009)

I could be wrong but this might be a clue....

And a little petrol (gas) on the fire is sometimes fun :angel:

http://www.archery.org/index.asp?link_id=54&cnt_id=7177


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## whiz-Oz (Jul 19, 2007)

Ah. 

Dr James Park. 
A very meticulous and dedicated individual, with a history of being a pretty good archer as well.

The research that is noted in the link is available online for a small fee at sage publications for those who would like to read it. 

http://pip.sagepub.com/content/223/4/139

J L Park1

1Department of Mechanical and Aerospace Engineering, Monash University, Wellington Road, Clayton, Victoria 3800, Australia.

Abstract

This paper provides a static and dynamic mathematical model for a single cam compound archery bow. The static performance is that seen by the archer in drawing and aiming the bow. The dynamic performance is of importance in determining how the arrow is accelerated and exits the bow. Building on the work of Hickman, it is shown that in order to flatten the arrow acceleration profile during the power stroke it is important to select a limb profile that minimizes the limb's effective mass and to use a heavy arrow. To minimize the time the string and arrow spend in the vicinity of the archer's face it is necessary to minimize the inertia of the bow's cams. Various aspects of the model have been validated, showing a good fit with experimental data. The conclusions are applicable to other compound bow configurations.

http://pip.sagepub.com/content/225/1/8

The Behaviour of An Arrow Shot from a Compound Archery Bow

J L Park1

1Department of Mechanical and Aerospace Engineering, Monash University, Wellington Road, Clayton, Victoria 3800, Australia,

Abstract

The behaviour of an arrow exiting an archery bow is of interest in relation to equipment selection and optimization, as well as to the performance of the arrow down-range. In particular, it is a necessary input into a study of the impact of archer technique errors and wind drift. While the performances of recurve archery bows have been modelled by a number of researchers, those of compound archery bows have not. A compound archery bow is mechanically more complex and the archer holds the string using a mechanical release device rather than with fingers directly on the string. Consequently the arrow behaviour is significantly different from that for a recurve bow.

This paper provides the results of an analysis of an arrow leaving a compound bow in both the vertical and the horizontal planes. Techniques similar to those used by Kooi for a recurve bow were used, together with photographs obtained using a triggered flash light. The paths taken by the bow's nocking point in both the vertical and the horizontal planes had a substantial influence on the arrow behaviour. In the vertical plane this was both measured and modelled for one bow type and for a second bow type it was modelled. In the horizontal plane it was measured and modelled for one bow type but with the locus varied by twisting the bow laterally.

Three sizes of the most commonly used arrows were examined: the recommended size, and arrows one and two sizes stiffer. It was concluded that both the recommended size and the stiffer sizes behaved similarly, giving increased scope to optimize arrow selection for parameters such as wind drift. One major archer technique error, namely twisting the bow, was included in the analysis and shown to have a significant impact on the arrow behaviour and the path taken by the arrow in the horizontal plane.


http://pip.sagepub.com/content/225/4/241

Arrow behaviour in free flight

J L Park

Department of Mechanical and Aerospace Engineering, Monash University, Wellington Road, Clayton, Victoria 3800, Australia. 

Abstract

As an arrow exits a bow, it may have a non-zero angle of attack in both the vertical and the horizontal planes. It might also have a non-zero angular rotation about its centre of mass and will probably be flexing longitudinally. In this paper, the arrow behaviour in free flight in the horizontal plane and without wind has been analysed. A finite difference method was used to solve the equations of motion. This was compared with the measured behaviour for arrows shot from a compound archery bow (although the results are also applicable for recurve bows).

Given typical initial conditions, the arrow oscillates longitudinally about its centre of mass, with the period and damping largely determined by the fletch area, and gains a lateral velocity component and lateral displacement. For normal fletch sizes the oscillation will be under-damped. In the absence of archer technique error, the longitudinal oscillation was found to have minimal effect on the accuracy.

http://pip.sagepub.com/content/224/2/141

Compound-archery-bow nocking-point locus in the vertical plane

J L Park1

1Department of Mechanical and Aerospace Engineering, Monash University, Wellington Road, Clayton, Victoria 3800, Australia

Abstract

In general, the path taken by the nocking point of an archery bow in the vertical plane is not a straight line perpendicular to the rest position of the string; it may vary significantly from that. Any deviation from a straight line at a draw length around the full-draw position will potentially lead to significant inaccuracy if the draw length varies by small amounts from arrow to arrow. This can occur for a compound bow if the cams do not come to their full-draw position simultaneously.

The path taken by the nocking point over the length of the bow's draw, and especially near the bow's brace height, can be expected to influence significantly the way that the arrow flexes and rotates about its centre of mass as it leaves the bow and enters the airstream. Hence it is of importance in relation to the arrow's position on the string relative to the bow's launcher (or arrow rest) at the brace height.

This paper provides a model for the nocking-point locus in the vertical plane. While examples are provided for several configurations of compound bow, it is generally applicable to longbows and recurve bows as well. It is noted that asymmetric degrees of freedom in the cam configuration of a compound bow are required if the nocking-point locus is to be both straight and perpendicular to the rest position of the string, and that this cannot be achieved for some compound-bow configurations or for a longbow or recurve bow unless the arrow pass is in the geometric centre of the string.


Interesting reading.


----------



## Joe T (Apr 5, 2003)

whiz-Oz said:


> Ah.
> 
> 
> Arrow behaviour in free flight
> ...


Whiz

Being the self proclaimed expert you are with a direct line "to heaven" perhaps you could answer a question re something that has puzzled me ever since I read the above paper.

i.e. how were the launch arrow "angle of attack" and the "angular velocity" actually measured.

I presume that "angle of attack" actually refers to "launch angle" (the two are often confused - ref the launch angular velocity).


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## whiz-Oz (Jul 19, 2007)

Joe T said:


> Whiz
> 
> Being the self proclaimed expert you are


I never said that I was an expert Joe. 

You've got access to the internet and Jim's email address. 
Ask him yourself.


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## limbwalker (Sep 26, 2003)

How on earth did the native people ever launch an arrow 10,000 years ago without all this "data" ?

Unbelievable.


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## Joe T (Apr 5, 2003)

limbwalker said:


> How on earth did the native people ever launch an arrow 10,000 years ago without all this "data" ?
> 
> Unbelievable.


Same method as used today - trial and error!
The rest is just typical bar room chat.


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## rharper (Apr 30, 2012)

limbwalker said:


> How on earth did the native people ever launch an arrow 10,000 years ago without all this "data" ?
> 
> Unbelievable.


They probably had terrible groupings! :wink:


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## ThomVis (Feb 21, 2012)

They needed 1 arrow in the right place to bring home food, we need 144. That's progress for you......


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## limbwalker (Sep 26, 2003)

Yea, but their life depended on how good they could shoot. Literally. 

No pressure. If you miss, you starve.


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## Flehrad (Oct 27, 2009)

Well, back then there were a lot more creatures running around, so missing once or twice in a day probably wasn't that bad, if you shot towards a herd, you probably still hit something lol


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## whiz-Oz (Jul 19, 2007)

Here's all the research on arrow point flow separation, for those interested in the evidence. 
There are already three alternative sets of tungsten points available to those who care about minimising point loss. 

http://pip.sagepub.com/content/227/1/64.full.pdf+html


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## fader (May 17, 2010)

Correct me if I'm wrong (I didn't stay at college long enough to get my phd), but the experiment seems to suggest that the shorter bulge points (i.e. the tungsten points) produce more drag then the long bulge points. Since they didn't actually test the long bulge point I don't see how they could say conclusively. Regardless, it's interesting that their testing brought them to that conclusion. Anyone still want to spend $250 on a set of points


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## Vittorio (Jul 17, 2003)

Just went very fast on the paper, so may be I have missed something, but:

1) it is obvious even without testing that a largere lateral surface is mor subject to lateral wind than a smaller one. It is intrsting to hear that deviation over 70 mt may average reach 6 mm between a bullet point and a bulge one
2) but the test has been made at theoretic level, not at practical level. No vibration in flight, no rotation
3) and the mass of the different practically existing points (steel vs tungsten) have not been considered, so the different FOC for the same arrow.

Probably, developping a bullet tungsten point may bring to 6 mm average group gain at 70 mt. Until then, in any case, advantages of tungsten points over steel ones remains huge because of the other factors.


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## mrface2112 (Jun 26, 2012)

limbwalker said:


> How on earth did the native people ever launch an arrow 10,000 years ago without all this "data" ?


 They spent time making arrows and shooting them instead of wasting time on teh interwebz...


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## Joe T (Apr 5, 2003)

Vittorio said:


> Just went very fast on the paper, so may be I have missed something, but:
> 
> 1) it is obvious even without testing that a largere lateral surface is mor subject to lateral wind than a smaller one. It is intrsting to hear that deviation over 70 mt may average reach 6 mm between a bullet point and a bulge one
> 2) but the test has been made at theoretic level, not at practical level. No vibration in flight, no rotation
> ...


Must never forget that "wind tunnel" type tests have no direct practical relevance to real (free flight) arrows. for example: - 



> It is obvious even without testing that a larger lateral surface is more subject to lateral wind than a smaller one


With an arrow fixed in a wind tunnel this is true but in free flight which has more wind drift a bare shaft or the larger lateral surface area fletched arrow.


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## limbwalker (Sep 26, 2003)

So, where does shaft planing (in the direction the point is aimed) play into this?

If we tune by using shaft planing as our guide, why then do we tend to ignore the value of the force of the air acting against the shaft to steer it in the direction of the point? In other words, the same skinny arrow that offers less cross section to a crosswind also offers less cross section to the air the effective 150 mph headwind it's facing too.


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## Houngan (Oct 19, 2007)

limbwalker said:


> So, where does shaft planing (in the direction the point is aimed) play into this?
> 
> If we tune by using shaft planing as our guide, why then do we tend to ignore the value of the force of the air acting against the shaft to steer it in the direction of the point? In other words, the same skinny arrow that offers less cross section to a crosswind also offers less cross section to the air the effective 150 mph headwind it's facing too.


It seems like that would only affect speed (drag) rather than accuracy, since the arrow is symmetrical and spinning in that direction. Much like the stupid in Wanted, if something is spinning along the long axis, then spinning it more or less won't make it turn, it will just make it more/less stable.


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## Joe T (Apr 5, 2003)

limbwalker said:


> So, where does shaft planing (in the direction the point is aimed) play into this?
> 
> If we tune by using shaft planing as our guide, why then do we tend to ignore the value of the force of the air acting against the shaft to steer it in the direction of the point? In other words, the same skinny arrow that offers less cross section to a crosswind also offers less cross section to the air the effective 150 mph headwind it's facing too.


The arrow is screwed to a mount so it doesn't "plane" anywhere .
I guess your question is really how does point design affect putting my arrows in the middle of the target. My *guess* is the real answer lies here:

"_Any shape other than a sphere generates a moment when inclined in an inviscid flow. The Munk moment arises because of the asymmetric location of the stagnation points, where the pressure is highest on the front of the body (decelerating flow) and lowest on the back (accelerating flow). Due to this fact, the Munk moment is always destabilizing, in the sense that it acts to turn the vehicle perpendicular to the flow. Traiantafyllou and Hover [2002]_"

Air flow separation from the arrow shaft magnifies the strength of the Munk moment on the arrow. You always get flow separation at the back. The Munk moment on an arrow is surprisingly large (about half your fletching area is used up compensating for it). If you have a point design which causes flow separation at the front as well then your just increasing the Munk moment torque and hence the arrow flight instability. To be fair you always compensate for Munk moment via fletching area and FOC. In summary for a given arrow switching a bullet point with a bulge point will probably increase the group sizes, increasing the fletching area to compensate will probably have a negative effect on the arrow wind drift. i.e. don't use bulge points.

As ever armchair theory doesn't win any medals. Only practical testing counts.


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## hoytshooter15 (Aug 13, 2012)

I agree with all of this. At my skill level, ranked 3rd in the state of Colorado for my class, I have no desire to buy the "best bow" hoyt has to offer. Because doesn't it seem weird that 2 or 3 years ago the old stuff was "the best"? Speaking of which, I'm looking for a pair of long Hoyt F3 or F4 limbs in 34 or 36 lbs. If anyone has a pair please PM me.


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## Joe T (Apr 5, 2003)

> As ever armchair theory doesn't win any medals. Only practical testing counts.


PS Should have included this archery related reference http://www.tap46home.plus.com/mechanics/fvort.htm

As an update to the old web page reference above, computer modelling of this effect (solving the leaf fall effect with Navier-Stokes for incompressible flow) has been under way in recent years at MIT (for the geeks  )



> If we tune by using shaft planing as our guide, why then do we tend to ignore the value of the force of the air acting against the shaft to steer it in the direction of the point? In other words, the same skinny arrow that offers less cross section to a crosswind also offers less cross section to the air the effective 150 mph headwind it's facing too.


John, this is exactly the significant point about the torque generated on the arrow by flow separation. As soon as the arrow rotates slightly then the full 150 mph wind (albeit at a low angle of attack) is acting to push the arrow sideways - and as this torque is maintained you have a runaway effect. As a practical test of this many years ago I shot a low FOC X7 bare shaft at an 80 yard target. Visually the arrow appeared to fly straight for what seemed like around 50 yards and dog legged sharply sideways ("planed" in your terminology). Only did this the once as it took me ****** ages to find the arrow even with a metal detector.


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## Joe T (Apr 5, 2003)

Attached is a simulation of this "planing". Worth noting that the onset of planing, in terms of distance, is very sensitive to the basic set up of the bow. Sometimes wonder if it is not a factor where archers arepuzzled by oddball arrow behaviour.


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