# Brace height and forgiveness



## robin smith (Jun 6, 2011)

I am currently shooting a 70" Axis w/ a 9.0" Bh @ 32# DL 30.5" amo 1/8"+tiller
Arrows are CX X-Buster 700 cut 30.250" nock to tip w/ 3" feathers pin nocks and 90 grn points

I was talking to Ted Light and I was telling him that my bow was tuned well but very touchy (unforgiving) and He suggested increasing my Bh to 9.375" will help make my shot a little more forgiving. I would like your opinion on this. 

I struggled for the first part of todays shoot and still managed a 507= 246+261 finished really strong 
would love to gain a little more forgiveness.


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## Dacer (Jun 10, 2013)

Try it and see. The arrow stays on the string for less time at a higher brace height.


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## robin smith (Jun 6, 2011)

With a week before mid-atlantic shoot I do not want to play games with my setup. Thus I bow to the experience of those better than I.


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## anmactire (Sep 4, 2012)

Easiest thing to do would be to get a second string and set it at the brace height you want to test on that one. You get to keep your old string length and test that variable. I have always felt that brace height choice is part of the tuning process, but it sure is a pain to move the nock point with every change in brace height. Brass nocks are good for doing the testing.

With one week to go though I wouldn't mess with anything that doesn't need fixing. Is it an 18m round you shot? I would say when I was shooting that level a change in brace height made less difference than what I had for breakfast that day. Still don't notice it too much until it's almost a quarter inch difference and my clearance is poor because the tune is now out.


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## dchan (Jun 29, 2004)

The best most forgiving brace height is the one that is quietest. That's why we do the BH tuning.

The adjustment of brace height unti it is quiet, means that the arrow releases from the string at the moment that the arrow is straight (between oscillations) and moving straight forward. If the nock leaves the string at a slight angle and you make the angle slghtly different by plucking the string, torquing the bow or the very many other ways we archers screw up the shot, you will affect the arrow more and thus make the bow less forgiving.

Depending on your tune, it's possible your BH is too high. Only trying it will determine its effectiveness,

If you switch strings, (try it with another string) you may learn something but depending on the string, your sweet spot on a different may be a different BH. A few extra wraps of center serving can slow the string speed enough to affect the tune.

Also, nock height does not need to change with every BH adjustment. Just keep twisting the string (or untwisting) until you find that quiet sweet spot, then move your BH.


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## Joe T (Apr 5, 2003)

To correct a common mistake an arrow is not straight when the nock separates from the string but is bent around the riser (the "Archers Paradox"). The following image (from Bertil Ollsen) nicely represents the arrow geometry at string separation.










The connection with forgiveness is that if the string plucks the nock on exit then the resultant arrow spin makes the arrow less forgiving. When the BH is adjusted to minimize shot noise/vibration your adjusting for "minimum plucking". Fine adjustment of any string-nock separation effects are made via normal tuning. Any subsequent bracing height adjustment is normally related to arrow clearance. As per the diagram the arrow nock has to move sideways enough to clear the riser/rest, the arrow has to become more or less straight as the nock passes the riser.


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## julle (Mar 1, 2009)

You can get the forgiveness in your form. If your shooting 507= 246+261 the last thing I would worry about is brace height. 

I can adjust my braceheight by 1/2" and expect it to hit exactly the same spot from 18 down to 90meters. But that's just weird, and maybe down to me doing something odd...

@Joe T

I could find myself in that theory, and I still think it's true to some level, but i'm not seeing a single difference with my highspeed camera.


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## Borderbows (Apr 4, 2009)

dchan said:


> The best most forgiving brace height is the one that is quietest. That's why we do the BH tuning.
> 
> The adjustment of brace height unti it is quiet, means that the arrow releases from the string at the moment that the arrow is straight (between oscillations) and moving straight forward. If the nock leaves the string at a slight angle and you make the angle slghtly different by plucking the string, torquing the bow or the very many other ways we archers screw up the shot, you will affect the arrow more and thus make the bow less forgiving.
> 
> ...


That is a conventional thought.
here is a complexity that messes with the waters a little.

A lot of our customers struggle with a little noise. and a lot of them are getting some arrow slap due to the arrow being too weak. if you increase the BH, you choke off some of the performance, and this in turn makes the arrow act a little stiffer. this means the slap doesn't happen.

The test of this is to reduce pound weight. and if the noise reduces its because the arrows aren't stiff enough.

but yes, the most forgiving is when the bow is in its sweet spot.

on a wider note... back to the topic


its possible to get arrow tune/clearance at 6.75" of brace height.
as everyone knows its also possible to get clearance at 10".

but I would like to add that the theory that the arrow is on less time is also wrong.
like any osculation the longer the oscillation has to act its course the smaller it gets. So if you could have a 70 meter power stroke. im sure the oscillations would be near on totally straight.

I like the idea that the arrow can be tuned to the bow, but the bow can be tuned to the arrow.

I watched a woman here, cut strands out the string, and as she went about this, her arrows went from stiff, to on tune. She was speeding up the bow to make her arrows tune in.
but then again, a month later a guy did the same thing, but he did it by putting twists in his string to tune his bow with BH.
but my dad does a lot of hit tuning with centreshot adjustment and point weight.
all these methods produce a tuned bow. and that to me is what forgiving is.

the idea that BH is unforgiving to me indicates that the bow was out of tune when the BH was changed.
same as string mass. "oh my, My bow is shooting really well with a 14 strand brand Y string, this string is really good" er no, its just hit a better sweet spot.
that's my opinion


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## Joe T (Apr 5, 2003)

julle said:


> @Joe T
> 
> I could find myself in that theory, and I still think it's true to some level, but i'm not seeing a single difference with my highspeed camera.


To actually see the string - nock separation you would need something like 16000 frames per second. Much easier to just do an overall bend count. Pretty obvious then what must be happening. The bent arrow on separation pretty much nailed down by Klopsteg in his explanation of the archers' paradox in the 1940's (and all theory & experiment since). The straight arrow was a (temporary) coach going off the rails story of the 1980's (nodes on the brain  )


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## midwayarcherywi (Sep 24, 2006)

There are many factors that go into creating a good tune. For me, every time I tuned slightly weak shafts well, I found the tune to be critical. I could shoot excellent groups, but the set up was unforgiving. Were I in your shoes, I'd opt for a slightly stiff arrow that I could tune well.


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## lksseven (Mar 21, 2010)

Borderbows said:


> That is a conventional thought.
> here is a complexity that messes with the waters a little.
> 
> _A lot of our customers struggle with a little noise. and a lot of them are getting some arrow slap due to the arrow being too weak. if you increase the BH, you choke off some of the performance, and this in turn makes the arrow act a little stiffer._ this means the slap doesn't happen.
> ...


Sid, I'm under the impression that increasing the BH makes the arrow act weaker, not stiffer. Can I get confirmation on which is the correct answer?


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## w8lon (Jun 2, 2012)

I am finding that a 8125 16 strand string with 70" bow is moving on me arrows start dropping out of the bottom after 40 arrows, so yes losing velocity. This is a well broken in string with thousands of arrows through it and only 30#'s OTF and will drop from my 9-3/8 brace to 9-1/8, right out the bottom of Gold. Will add 4-6 twists and right back in there, no side to side compensation needed. My other strings by same maker in 68" with heavier poundage remain stable, I see no sign of failure with the 70" string. Instability in the extra two inches of length?


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## Dacer (Jun 10, 2013)

robin smith said:


> With a week before mid-atlantic shoot I do not want to play games with my setup. Thus I bow to the experience of those better than I.




I'll echo what another said - with the scores you posted there are larger factors than your BH to address. You said your bow is well tuned, then I would say this, Your bow is only doing what YOU tell it to do. One of the things I say to myself, ' its not my bow that made the bad shot - it was me'. No problem gathering opinions or starting a topic of discussion. There is some interesting debate and information being posted. But from my own experience, I suggest you put your mind at ease about your equipment and just focus on you. Shoot a lot of blank bale, use a form master type device, and so on. 




on another note: 
Since you don't want to doing any testing. I put your specifications into my _SuperSpecs archery program_ and is says the your BH should be 9.21992" inches for _optimal performance._


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## Dacer (Jun 10, 2013)

lksseven said:


> Sid, I'm under the impression that increasing the BH makes the arrow act weaker, not stiffer. Can I get confirmation on which is the correct answer?


Everything I've read agrees with you. From Viper1 to Kaminski- say that a higher BH causes a weaker dynamic spine.


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## Borderbows (Apr 4, 2009)

ah, sorry... yes, with more than a one cycle paradox.

we are not quite getting the same paradox cycle.

let me see if I can find the post over on AIUK.


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## Borderbows (Apr 4, 2009)

http://www.archeryinterchange.com/f127/hexs-make-me-scratch-my-head-184488/

I think this is it.


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## w8lon (Jun 2, 2012)

We need high speed film footage along with chronograph readings to go along with this with a 1/4" brace ht change. In theory shots should be higher with gained velocity of a lower brace height. I think this is true up to a point but with my setup shots are going lower and 2-3 clicks left after the creep sets in (left hand shooter). Would nock drag leaving the string as it is under lower preload/tension with a lowered brace height induce a lower shot? I am using a very low nock to string tension with the Dodge Pro Nocks, old school twist on to swage of X7's, so wouldn't think this would have too much effect.

Perhaps more oscillation due to lower brace and gained velocity at start is in actuality robbing arrow speed at distance.


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## Borderbows (Apr 4, 2009)

w8lon said:


> We need high speed film footage along with chronograph readings to go along with this with a 1/4" brace ht change. In theory shots should be higher with gained velocity of a lower brace height. I think this is true up to a point but with my setup shots are going lower and 2-3 clicks left after the creep sets in (left hand shooter). Would nock drag leaving the string as it is under lower preload/tension with a lowered brace height induce a lower shot? I am using a very low nock to string tension with the Dodge Pro Nocks, old school twist on to swage of X7's, so wouldn't think this would have too much effect.
> 
> Perhaps more oscillation due to lower brace and gained velocity at start is in actuality robbing arrow speed at distance.


with lower unsupported string, (ei supported in a string groove) the string is supported by a wider part of the limb, you start messing with the frequency. The issue is compounded by a increase in speed, which means we think we are on a different part of the oscialtion on separation. so yes, I can see the reaction weak vs stiff being the case. we are not sure we have a full cycle, while the conventional thoeries are that the separation happens on the second cycle.


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## midwayarcherywi (Sep 24, 2006)

Ok. This guy is trying to get ready for a tournament and I don't think we are doing him much of a service by talking about tuning. It seems pretty clear he just needs to focus on making his shot on a consistent basis and clear his mind of equipment thoughts and tuning. 

Robin, grab your gear and make strong confident shots. Worry about the other stuff later.


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## robin smith (Jun 6, 2011)

I am a printing press tech so bow being right helps my mind be right. that said I also believe I still have a long way to improve. Knowledge and experience go hand in hand at 52 years old and only shooting a recurve for a year I am using you all as my knowledge base. I am getting more consistent every week because I am putting in the work shooting between 500-1000+ arrows a week. I have a good coach that I see once a week. But I sometime need real time answeres and you guys are the best. To which end I Thank You for your help and if I ever meet up with you at a shoot I would be glad to take some of you to breakfast or buy a round of drinks. My coach says I am about ready to start on clicker but he does not want me to start until indoor season shoots are over.



midwayarcherywi said:


> Ok. This guy is trying to get ready for a tournament and I don't think we are doing him much of a service by talking about tuning. It seems pretty clear he just needs to focus on making his shot on a consistent basis and clear his mind of equipment thoughts and tuning.
> 
> Robin, grab your gear and make strong confident shots. Worry about the other stuff later.


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## w8lon (Jun 2, 2012)

midway, I too have NFAA Sectionals this weekend I find pondering these subjects throughout the shot process calming in knowing the equipment. When things start to go south and the shot feels good then is the time to analyze what is changing. Last weekend a few points were lost with high/low shots shooting my BHFS compound it was figured out with a high arrow then next one low that my scope hood was rotating every shot. The pin finally pointed straight up, no hand was raised, instead the two wrenches that I needed were drawn from the quiver and the nuts tightened. Last three arrows made it to the target with five seconds to spare.


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## midwayarcherywi (Sep 24, 2006)

There is a big difference between fixing broken equipment and trying to change your tune ahead of an event. I suppose everyone is wired differently.


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## Fury90flier (Jun 27, 2012)

Ok...Real answer- Get warmed up- 

1. go shoot for group with your current setup--remember, it's GROUP SIZE- we don't care where it goes.
2. measure group- ouside of the two arrows farthest appart
3. go shoot for group with the new suggested bh
4. measure group.

5. see which group is smaller-- use the smaller group seutp.

possibly will need to tweak plunger settings to see maximum benefit.

if between the two you find no difference in grouping...go back to the origial. OR, do some brace height tuning- it doesn't take that long...can be done in a day.

if you do notice a difference- spend the day shooting at that height--- if it works, great.



so, you're talking about a days worth of shooting to see if it will improve your scores...we're not talking trying a different grip, or different hook style- a simple BH change--that won't affect your form if you go with it or not. 

Is it worth a day playing or is that time better off with a coach?


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## DK Lieu (Apr 6, 2011)

I’ve been asked many times for my opinions about the effects of brace height on tuning, specifically how or why changing the brace height changes the sound of the bow, and whether or not there is an “ideal” brace height from a tuning point of view. To be honest, I have so many other (form related) issues that I haven’t given it much thought. But since the questions keep popping up, I think I’ll give a shot at a theoretical explanation of what is happening. Yes, I would expect changing the brace height to change the sound that a bow makes, but so do many other things. For example, I’ve been able to get my bow to become significantly quieter by changing the way I build the end-loops on my bow string. But let’s look specifically at the effect of brace height. When a bow is drawn back and the arrow is loosed, several things happen. Besides the arrow obviously being propelled forward, the string (with the tail of the arrow) is deflected laterally, and the arrow starts to bend, as shown in the diagram below.









We now have a coupled system, both of which are flexible and therefore complex. The bow wants to do one thing while the arrow wants to do another. The bow wants to return the string to the neutral position, while the arrow wants to continue to flex at its natural frequencies as it goes forward. Then the two systems suddenly disengage when the nock breaks free of the string. So… is there an ideal location in the process where the disengagement should occur? I believe that the best time to disengage is when the two systems have the least effect on each other. For the forward travel of the arrow, this is where the string has returned to the neutral position because the forward acceleration of both the string and the arrow are zero at this location, so one system no longer imparts force to the other. But remember that there is also a lateral deflection, and the string will also want to return to its neutral position in that direction as well. Looking at the arrow vibrating at its (first ) natural frequency, is there a place in the vibration cycle where the arrow will not impart force to the string, so that neither system is forcing the other to do something? The diagram below shows the approximate vibration cycle of the arrow in relation to the approximate location of the arrow with respect to the bow as the arrow travels forward. It can be seen that at one full cycle, the arrow deformation amplitude is zero, and the lateral velocity of the tail and tip are at their maximum. This means that the lateral acceleration of the tail and tip are zero, and thus at this point in time the arrow will impart no lateral force to the string. Thus the brace height should be set to release the arrow at this point in time, because this is where the two systems can be separated without a sudden change in mutually applied force. 









If the nock is released at a non-ideal position, there will be a sudden change in force, as if you are pushing a mass, and then the mass suddenly disappears. It’s similar to plucking the string without an arrow, which we all know creates… noise. So… how do you find the brace height to achieve this ideal separation? It depends on the vibration frequency of the arrow, which depends on its stiffness, point and tail masses, and the mass density of the shaft. It also depends on the speed of the arrow, which depends on limb design. You can certainly measure the frequency of the arrow after it is fully built, measure the speed of the arrow when loosed, make a few assumptions, and then do the calculation. Or you can do what I do, which is to mess with the brace height until it sounds about right. Less work and more fun that way.


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## w8lon (Jun 2, 2012)

Good stuff, Dennis. Thank you!


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## Viper1 (Aug 21, 2003)

Guys - 

You can really over complicate this.

As dchan said, the bow will be most forgiving when the arrow nock disengages the string as the string approaches center line of the bow, since that should allow the greatest variation. That's why/how we tune for spine. 
A taller brace height, should give the arrow a shorter string time, giving the shooter less time to screw up. 
A taller brace height should allow the use of a stiffer arrow, which some people believe may be more forgiving. 

In the 60's and 70's, some bows, especially longer indoor rigs, were sporting 10", 11" and sometimes greater brace heights. 

Now, the question becomes how much of a difference in brace height is required to give a noticeable difference in "forgiveness"? 
I have no idea, but I'm willing to bet it ain't 1/4".

Viper1 out.


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## Borderbows (Apr 4, 2009)

id disagree with your two comments on higher brace height there viper
unless you have some evidence on this id say its speculation



Viper1 said:


> Guys -
> 
> You can really over complicate this.
> 
> ...


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## Warbow (Apr 18, 2006)

Joe T said:


> To actually see the string - nock separation you would need something like 16000 frames per second. Much easier to just do an overall bend count. Pretty obvious then what must be happening. The bent arrow on separation pretty much nailed down by Klopsteg in his explanation of the archers' paradox in the 1940's (and all theory & experiment since). The straight arrow was a (temporary) coach going off the rails story of the 1980's (nodes on the brain  )


Perhaps true if you need the info in a single take with no redos. If you record multiple takes at a slower fps you'll eventually get one that is at the time of string seperation, if you shutter speed is high enough to see the arrow, that is. But, yeah, you still need some serious frame rates.


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## dchan (Jun 29, 2004)

The point I was making is not the "straight arrow" at release but a clean release of the string from the nock. We can argue forever when that happens and in what part of the recovery of the arrow, but as viper says, the clean release is what we strive for. 
Also as mentioned, at the scores posted, at 18M, there are a lot more things that need to be fixed. That being said, nothing wrong with trying to wrap your head around the process. Just don't let it get in the way of going out and shooting. Just don't obsess too much about it. especially right before an event..


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## Joe T (Apr 5, 2003)

Warbow said:


> Perhaps true if you need the info in a single take with no redos. If you record multiple takes at a slower fps you'll eventually get one that is at the time of string seperation, if you shutter speed is high enough to see the arrow, that is. But, yeah, you still need some serious frame rates.


I've never had much success with lotteries or raffles 
Nearest image to catching the separation I've seen is with a Park Sung Hyun video here brace height.

Full video is at http://www.youtube.com/watch?v=SuHW8InB5tk


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## julle (Mar 1, 2009)

This is what i get from a cheap camera, under reasonable conditions. 
I must say the arrow tuned a bit weak in this video(bareshaft in the blue @ 18m), but still my arrow sways this much sideways if it's correctly tuned. would you think this is a braceheight issue...?

In this video it also seems to sway quite a bit, and I think this is Seranno from mexico. But I have no idea if this is supposed to be an example of good or bad tune...


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## robin smith (Jun 6, 2011)

Thanks guys for the great info guys I really appreciate it. I adjusted my BH by 3/16" and it did quiet it down some more. I got very good results after with bare shafts as well. About 1/2" to the right of fletched and 3/4" high and they were touching each other. my coach laughed at me and said random acts of archery LOL. His way of keeping my head from getting too swelled, I love it. yes I know that means they are slightly on the stiff side.


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## Vittorio (Jul 17, 2003)

Fogiveness from BH is more related to vertical stability of limbs than to dynamic spine changes. Koreans for instance prefer very high brace height for this, while I usually tune initial BH were vertical movement of the string is as small as possible ... quite often result is same, but not ever. Sid may explain why ( is related to limbs curves and structure) ...


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## robin smith (Jun 6, 2011)

Thanks Vittorio my coach explained the same thing he watched me shoot to see if my limbs finished at the same time . He was happy with the results.


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## MAT (May 27, 2003)

DK Lieu said:


> We now have a coupled system, both of which are flexible and therefore complex. The bow wants to do one thing while the arrow wants to do another. The bow wants to return the string to the neutral position, while the arrow wants to continue to flex at its natural frequencies as it goes forward. Then the two systems suddenly disengage when the nock breaks free of the string.


This is fascinating. One question for DK Lieu, does your statement above assume the arrow and string frequencies are the same? Would they not have to be to separate at the time of zero acceleration?


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## Dacer (Jun 10, 2013)

robin smith said:


> Thanks guys for the great info guys I really appreciate it. I adjusted my BH by 3/16" and it did quiet it down some more. I got very good results after with bare shafts as well. About 1/2" to the right of fletched and 3/4" high and they were touching each other. my coach laughed at me and said random acts of archery LOL. His way of keeping my head from getting too swelled, I love it. yes I know that means they are slightly on the stiff side.


Actually if you are shooting RH and they land to the right. They are weak not stiff. Stiff left, Weak right for RH.



robin smith said:


> Thanks Vittorio my coach explained the same thing he watched me shoot to see if my limbs finished at the same time . He was happy with the results.


I wish I had eyes that could see that well. being able to visually tell the difference of 0.001s of seconds would be pretty awesome. 

Glad to see that you gave it a try and its working for you. From my experiments there are two places in BH range that will give quiet-ish shots but the bow reaction feels just a little-_slightly_ different. One gives a more a jump at the shot with a "snap" sort sound. and the other kinda just makes the bow roll forward with more of a thud sound. IDK maybe its just me hearing things.


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## DK Lieu (Apr 6, 2011)

MAT said:


> This is fascinating. One question for DK Lieu, does your statement above assume the arrow and string frequencies are the same? Would they not have to be to separate at the time of zero acceleration?


When the arrow and the string are connected, they (of course) move together and thus have the same frequency. When they are separated, they each want to do something different, because their frequencies will be different. The trick is to separate the two at a point where both want to do the same thing as when they are separate.


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## chrstphr (Nov 23, 2005)

DK Lieu said:


> When the arrow and the string are connected, they (of course) move together and thus have the same frequency. When they are separated, they each want to do something different, because their frequencies will be different. The trick is to separate the two at a point where both want to do the same thing as when they are separate.


best explanation yet.


Chris


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## robin smith (Jun 6, 2011)

Dacer said:


> Actually if you are shooting RH and they land to the right. They are weak not stiff. Stiff left, Weak right for RH.
> 
> you are correct I mistyped, sorry
> 
> ...


It started out more of a snap sound and as I increased the BH it got softer and bare shafts moved from being slightly weak hitting on the right side to very slight stiff (Hitting just to the left side). The other thing I noticed is my nock hieght changed it is now down to a 1/16" above the rest. I need to retie my nock points.


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## limbwalker (Sep 26, 2003)

You guys are making me really happy that I don't worry about this stuff. ha, ha.

DK - great explanation. I'm sure there's some plane of existence where what you describe could be achieved. 

This is great stuff, don't get me wrong. But if we all spent as much time dissecting our mental game as we do our brace height setting, I think we'd all be ahead of the game.


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## grantmac (May 31, 2007)

robin smith said:


> It started out more of a snap sound and as I increased the BH it got softer and bare shafts moved from being slightly weak hitting on the right side to very slight stiff (Hitting just to the left side). The other thing I noticed is my nock hieght changed it is now down to a 1/16" above the rest. I need to retie my nock points.


Sounds like you were getting a false reading due to the back of the shaft making contact. Something I was chasing my tail with a month or so ago.

-Grant


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## MAT (May 27, 2003)

DK Lieu said:


> When the arrow and the string are connected, they (of course) move together and thus have the same frequency. When they are separated, they each want to do something different, because their frequencies will be different. The trick is to separate the two at a point where both want to do the same thing as when they are separate.


So how does arrow spine enter into this equation? If the string/arrow is at one before separation the arrow spine will affect the frequency, right? Or other factors affecting frequency like weight? So BH might need to change as spine/weight changes. After separation the rest of the arrow travel (brace height) the arrow is vibration at its natural frequency, which we can measure. That’s adding more complexity than I thought possible.

So, is this arrow/nock separation phenomenon the reason why in bare shaft testing weak arrows fly nock left and stiff nock right?


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## Warbow (Apr 18, 2006)

limbwalker said:


> This is great stuff, don't get me wrong. But if we all spent as much time dissecting our mental game as we do our brace height setting, I think we'd all be ahead of the game.


Mental game hard. Buying stuff easy. :wink:


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## DK Lieu (Apr 6, 2011)

MAT said:


> So how does arrow spine enter into this equation? If the string/arrow is at one before separation the arrow spine will affect the frequency, right? Or other factors affecting frequency like weight? So BH might need to change as spine/weight changes. After separation the rest of the arrow travel (brace height) the arrow is vibration at its natural frequency, which we can measure. That’s adding more complexity than I thought possible.
> 
> So, is this arrow/nock separation phenomenon the reason why in bare shaft testing weak arrows fly nock left and stiff nock right?


I consider tuning via the bare-shaft method and bow clearance due to arrow frequency to be two separate phenomena, although the variables that affect one usually affect the other. An ideal set-up will have both good tune and good clearance, but it is certainly possible to have one without the other. For example, if you add mass to the tip of the arrow, you will decrease the arrow frequency but the tune will be weaker. On the other hand, if you add mass to the tail of the arrow, you will again decrease the arrow frequency but the tune will be stiffer. Increasing spine, while holding all other variables constant, will increase the frequency of the arrow. The arrow will vibrate through its cycles faster, and the neutral (zero-amplitude) deformation state will be achieved sooner. As a result, the brace height will need to be correspondingly higher so it can reach its neutral state sooner.


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## DK Lieu (Apr 6, 2011)

DK Lieu said:


> I consider tuning via the bare-shaft method and bow clearance due to arrow frequency to be two separate phenomena, although the variables that affect one usually affect the other. An ideal set-up will have both good tune and good clearance, but it is certainly possible to have one without the other. For example, if you add mass to the tip of the arrow, you will decrease the arrow frequency but the tune will be weaker. On the other hand, if you add mass to the tail of the arrow, you will again decrease the arrow frequency but the tune will be stiffer. Increasing spine, while holding all other variables constant, will increase the frequency of the arrow. The arrow will vibrate through its cycles faster, and the neutral (zero-amplitude) deformation state will be achieved sooner. As a result, the brace height will need to be correspondingly higher so it can reach its neutral state sooner.


Sorry, I meant _decreasing_ the spine (or increasing the stiffness of the shaft) will increase the frequency of the arrow.


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## limbwalker (Sep 26, 2003)

Warbow said:


> Mental game hard. Buying stuff easy. :wink:


Mental game free. Buying stuff, expensive.


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