Tag Archives: Tuning

Barebow, Barebow, Barebow

I just got an email from a viewer who had a boatload of questions about Barebow. (Hooray!) I love it when you send in your questions as it gives me ideas about what I should write about, so if you have them, please feel free to email them to me (ruis.steve@gmail.com).

Here’s Dieter’s questions:
So, the questions are:
• Does one have to close one eye when aiming off the point?
• My kind of split vision string- and face walking does work. However, did you come across someone who managed to combine the more “instinctive” split vision technique with aiming off the point brought right below the target without having to drastically alter button spring tension?
• Of course, I could decide for either technique. The benefit of split vision from 5 – 25 meters is, I do not need to crawl down the string and thus do not imbalance the bow. The other thing is losing accuracy on longer distances. I might also improve the closer distances aiming off the point.
• Maybe, my little problem is confusing. However, I’d be glad if you could share your experienced thoughts with me.
Best wishes, Dieter

* * *

And here are my attempts at answers! (Note I assume Dieter is referring to Barebow Recurve.)

  • Does one have to close one eye when aiming off the point?
    My opinion is that this is only necessary if there is a problem with keeping the off eye open. I, for example, shoot right-handed but am left-eye dominant. If I don’t half shut my off eye, I can end up with some bad misses. There are problems with shutting the eye completely (as with an “eye patch”) as this lowers the total amount of light coming into the eyes and therefore affects iris responses, etc. Eyelids allow some light it and people with glasses often resort to putting a strip of transparent tape over the off eye lens. This allows light in to an open eye but no clear image, so if the off eye “takes over” it will be easily noticed.
    This is the same whether you are aiming off the point and or using a sight.
  • … did you come across someone who managed to combine the more “instinctive” split vision technique with aiming off the point brought right below the target without having to drastically alter button spring tension? This is a very complex question. The “split vision” technique, as recommended by the likes of Howard Hill, is not really split vision as much as it is split attention. I am not a fan because while you are aiming that is the only time you are splitting your attention on what you are doing during an archery shot: you are attending to aiming and attending to completing the shot via swinging the draw elbow around, squeezing back muscles, or whatever. Splitting your aiming attention in two results in a three-way split in attention, something I am not a fan of. But then, I am a fan of whatever works, as long as we know what actually works, so if the “split vision technique really works for you, then go for it. (That you asked the question indicates it is not working well enough or under the circumstances you encounter.)
    Two topics are being addressed here in addition. One can aim off of the point several ways. The two primary ways are gap shooting (basically aiming off, with “gaps” being the amount of high or low aiming) and stringwalking. Since the grip of bow and sting do not vary when gap shooting, no adjustment of plunger tension is needed. However, when string walking, whenever the “crawl” (the distance down from the arrow the string is “gripped”) is changed, you are essentially de-tuning the bow. The draw length changes, the draw weight changes, the tiller changes, everything. These changes are small and successful Barebow Recurve stringwalkers focus heavily in finding a bow tune that represents a “happy medium compromise.” Usually, since the shorter distances are shorter and therefore easier (in field archery) they allow for a poorer tune there and set up for a better tune for the longer, and therefore harder, shots.

    Taking a crawl on a longbow.

    So, elite Barebow Recurve Archers who stringwalk have this unavoidable dilemma. Some use plunger adjustments at the extremes of their distances to help with this problem, so you are not wrong in doing that. The ultimate tune, though, for such an archer is one that doesn’t involve such adjustments, so these archers work on their arrows obsessively and their plungers to find a “no fiddling tune” if they can. If such plunger adjustments are required, you need to adjust your shot sequence to make sure that you add or subtract known numbers of turns on your plunger button and then take them off when no longer needed. Forgetting to do these things are mental mistakes that always lower scores, so eliminating the need to make such adjustments reduces the number of possible mental mistakes, which is a good thing … if you can pull it off.
    Sorry, for being so long winded on this one, but that’s the best I can do. Possibly more expert Barebow archers will chime in in the Comments.

  • Of course, I could decide for either technique. Yes, you can. There are some who insist that this technique is better than that technique. I have never seen a case in which this has been proven, unless you put up some form of standard technique against, say, standing with your back to the target. The entire reason we all shoot much the same way, with only minor differences, is that in the 60,000–70,000 year history of archery, the bow has taught us what works and what doesn’t. So, most of what you can find being currently recommended by archers and coaches works! That’s the good news. The bad news is “so does all of the other stuff.”And the only way you can tell “what works for you” is to try things out. Unfortunately, the things being tested against one another are so similar (they may feel really different, but they are not … to the point that onlookers may not notice that you have changed anything) that it takes many weeks of trying out the new thing to see if there is a real effect or not. There are very many things to try, and not enough time and effort to try them all, so you just have to pick.

    What I do know is this: the key factors are whether an archer has committed to a new/different technique and practiced it in and … in my not so humble opinion … simpler is better. If you try an aiming technique and it only works for shorter distances and you need another for longer distances, I would keep looking. What you want is a technique that is the same for all shots you take on a certain course, e.g. WA Field Unmarked shots are never longer than 50 m, WA target shots used to be longer (30-90 m for men) but now seem to have been shrunk down to just 50 m for target events. I would have separate bows set up for the two kinds of events. If I couldn’t afford two bows, I would have two bowstrings and two sets of bow settings for the two events. I might also, depending on budget, have two sets of arrows tuned for two different events. (Consider archer’s arrow choices for indoor and outdoor events as a model.) The gold standard for FITA Field Barebow archers shooting unmarked targets is a single anchor with a single set of crawls from 50 m on down to the shortest shot (don’t remember this … 5 m?).

    I prefer having a single technique for a single event. When I teach stringwalking, we start at close up, determining the archers point on target distance (POT) and then determining their set of crawls for distances inside that distance. Then we change from a high anchor to a low anchor and determine the new POT for that anchor (much farther out) and a set of crawls there, too. (Often the crawls are amazingly consistent, e.g. the same crawl for five meters closer than POT distance for both anchors, which makes memory mistakes less likely). What we hope is these two ranges overlap, covering all of the distances being shot. If they do not, instead of adding a third technique, we look to changing things like draw weight or slight changes in anchor hand position to get what is desired.

My rule of simplicity would rule out string walking as a tool for tackling a FITA Round, for example. There were/are only four distances. It is far easier to determine four points of aim for the four distances (if they are on target) than employ stringwalking with its detuning characteristics. But for a Field Round in which targets are placed at many different distances, having a different point of aim for each target is too cumbersome, there stringwalking shines. So, there are legitimate reasons for having a “bag of tricks” to employ for aiming at various kinds of events as “one size never fits all!”

I hope this helps more than it hinders!

Advertisements

2 Comments

Filed under For All Coaches, Q & A

Barebow Arrow Considerations

There is an upsurge in interest in Barebow, both Recurve and Compound. (Yeah!) This is accompanied by increased levels of confusion regarding the role the arrow plays in the ability to shoot consistently.

Since there are many Barebow aiming variations (gap shooting, “instinctive” shooting, string walking, face walking, etc.) I am going to hop over these variations (all of which create tuning issues) and move to the heart of the matter: aiming off of the point.

Aiming Off of the Point
Using the arrow point as an aiming support brings many advantages and a few disadvantages. One disadvantage is it makes draw length even more crucial. For example, consider that the nock end of the arrow is below the aiming eye and the sightline. The line of sight being even with the arrow point means that the arrow is slanting upward (as it is with other styles, of course). Now, if you draw your bow a bit too far, the arrow slides back and downward lowering the arrow point, causing you to raise your bow up to get the point back to the sightline. Drawing your bow a bit long results in high arrow hit points in that you’ve made the bow a tad stronger, but raising the bow also contributes to high arrow hit points, so this “positive feedback” results in larger errors. Similarly, a short drawn bow, results in the arrow sticking out and up farther, which results in you lowering the bow, another double whammy! (This effect is prominent for longbow and recurve archers, less so for compound archers.)

Aiming off of the point makes draw length control particularly crucial. On the plus side it provides amplified feedback in that regard and so may contribute to better draw length control. There are many other aspects of aiming off the point we leave to your further investigation.

The Effect of Arrow Length
The effects of variations in draw length can be made permanent by choosing a shorter or longer arrow. A longer arrow will result in a lower hold of the bow. A shorter arrow will result in a higher hold. So, for indoor targets, a longer arrow can be an advantage. Indoors, the distances are so short that most bows are over-powered. This results in points of aim (POA) being very low, off of the target face and maybe on the floor where there are few visual clues as to where the POA is. We would like to have a POA on the target face as a face provides many visual cues as to the POA’s location (e.g. a POA at 12 o’clock in the 5-ring). So, for indoors, most people favor a longer arrow. This cause the hold to be lower and the POA higher. Since the length of the arrow is one of the largest aspects affecting the tune, a stiffer shaft has to be chosen to compensate for the extra length.

Outdoors, the distances are much larger, and bows tend to be under-powered. Here a shorter shaft provides a higher hold, a lower POA, and more cast, but we need a weaker shaft so we can cut it as short as we can.

We accept as a given that one’s form will be more consistent when the arrow is near level than when the bow is held with the arrow slanted way up or way down. So, the closer you can create a setup, for you or your student, that is near that situation, the better.

Arrow selection is not a simple matter of just checking a manufacturer’s spine chart and selecting the shaft closest to the characteristics your archer possesses (DW and DL and bow type). In most spine charts, the entire row of choices determined by the DW are available to you. Limited only by arrows that are too short (as they are dangerous). Here is a row from a simplified spine chart:

Compound Bow

21˝ 22˝ 23˝ 24˝ 25˝ 26˝ 27˝ 28˝ 29˝ 30˝ 31˝ 32˝ Recurve Bow
29-35 lb 1214 1214 1413 1416 1516 1713 1716 1813/
1816
1913 2013/
1916
2013/
1916

17-23 lb

Assuming this is the correct DW row, if the archer’s draw length is 24˝ AMO, a 1413 aluminum arrow is recommended. Shorter shafts are possible, but remember the arrow point is typically only about 1.75˝ ahead of the arrow rest at full draw, so a 1214 shaft could be used, cut to 23˝ but I wouldn’t go shorter. Other choices are: the entire rest of the row:
a 1416 shaft, cut to 25˝
a 1516 shaft, cut to 26˝
a 1713 shaft, cut to 27˝
a 1716 shaft, cut to 28˝
a 1813/1816 shaft, cut to 29˝
a 1913 shaft, cut to 30˝
a 2013/1916 shaft, cut to 31˝
a 2013/1916, cut to 32˝

All of these shafts and cut lengths should produce arrows of comparable performance. Keep in mind this is not this simple. As we move across this table row, the arrow shafts are getting heavier and we are losing cast thereby. (There are other issues, but this post is too long already.) All parameters in a spine chart, therefore, need to be taken with a grain of salt and if you desire to experiment with different length arrows, always (Always!) start with a longer shaft and cut it down in stages, testing for tune as you go (a bare shaft test is all that is necessary).

A Note Regarding Young Archers
Archers who haven’t achieved full growth probably should not play around with these ideas. For one, they are still growing and as their height increases, so does their draw length. Ordinarily I like to have at least 1˝–2˝ of extra length on their arrows just for safety (and the ability to shorten the shaft to get a better tune as they grow). These youngsters are better off working on their fitness and shooting form and execution than fiddling with equipment to get a slight advantage.

If a youngster, however, is having trouble “making distance,” the problem may be exacerbated by an arrow that is too long. I have seen some sticking out more than 5˝ past the back of the bow. In this case, a better fitting, resulting in a shorter arrow should help.

7 Comments

Filed under For All Coaches

Breaking News! Archery is Counterintuitive!

I got the following email from my best student this morning:
“Okay coach, explain this one to me. Increasing my bow weight seems to make my arrows shoot more to the left. Compounding my confusion is that tonight I got the groups to move back to the right by tightening my plunger. Count me confused and dazed!
Cheers

If this has never happened to you, you haven’t been in archery very long. The student in question shoots Olympic Recurve, so you have that as background. Here is what I answered, expanded for this post).

* * *

A bow is a closed system, when you change one part, many others are affected. (Memorize this!)

You got two counterintuitive responses to things you did. The problem is that ceteras parabus was nowhere to be seen. (Ceteras parabus is the principle that “everything else was the same.”) When you make a single change to a bow, you make other changes, too … always! There is no such thing as “everything else was the same” when working with bows.

For example, you increased your draw weight. I do not know how much but it was not a fraction of a pound is my guess. When you screw in the limb bolts, you change the angle of the limbs to the bow (making the limbs more upright as it were). This results in a lower brace height. (Plus more tension on the string at brace, plus …) The brace height is one of the determinants of the point in space at which your arrow’s nocks separate from your string at the end of the power stroke. Since the string’s path toward the riser is a flattish “S curve,” the change in the point of separation of the string and nock is complex. If the nock comes off more to the right from where it did previously, the arrow ends up pointed more to the left (the point has enough inertia that it doesn’t move as much as the nock end). If the nock comes off more to the left, the arrow will be pointed more to the right. (Think about it.) I have also to point out that when the arrow separates from the string it is no longer touching the arrow rest.

“Coaches need to expect counterintuitive responses to equipment changes.”

When you change the bow’s draw weight, you are also changing the efficiency of the bow due to a spine match or mismatch. I think I told you about the compound archer who lowered his draw weight (just a half turn on each limb) only to have his arrows hit higher on the target. What happened when he lowered the draw weight,  he created a better spine match (arrow to bow), which created a more efficient transfer of energy from bow to arrow which made up for the energy loss from the change in draw weight and more. These are the kinds of counterintuitive things that can happen.

If we had created a perfect spine match for your bow before (unlikely, such things take a great deal of time and effort), we no longer have that spine match. When you finish your draw weight changes, a complete re-tune is necessary because so many things have changed.

If you think the string goes straight toward the riser, think again. (Yeah, this is a stringwalking Barebow archer, but I get to exaggerate for emphasis, don’t I?)

A general consequence of this situation (reality actually) is coaches need to expect counterintuitive responses to equipment changes. This is because of the reasons stated and because what you were taught were often oversimplified rules of thumb. For example, “weak arrows fly to the right, stiff arrows fly to the left.” and “If you lower the nocking point, you will raise the hit point of the arrow on the target.” (All of these are for right-handed archers.)

These equipment aphorisms were intended to get you down the road until you could think through such problems without needing them. From a perfectly tuned bow, if the nocking point is lowered a slight amount, the arrow will hit on the target lower than it did previously. But if you lower the nocking point enough, the rear of the arrow will start hitting the rest or arrow shelf and where those arrows land is anybodies guess.

All of those pithy little rules need to be taken with a grain of salt. And, they need to be thought through as they are all true … up to a point. By thinking them through they provide an entry to better understanding of archery equipment. If you do not, they become unreliable crutches. (I am speaking from experience here. If I had a nickel for every mistake I made, I could have retired earlier.)

6 Comments

Filed under For All Coaches, Q & A

Tuning the Genesis Bow Follow-up

QandA logoI got a follow-up email regarding the Genesis tuning problem.

With NASP unfortunately we can’t change the arrow in any way and must use the Easton 1820 “Genesis Arrow” so it seems we’re left to play with nock height and repeatable form. Is that how you see it?

This is the case for official NASP competitions. My previous answer was for the broader archery community and competitions out it the wonderful world of archery outside of NASP. Here’s my answer to this email:

* * *

Yep, it is somewhat of a trap. The idea is to have a level playing field (same bow, arrow, target, distance) and I agree with that. Poor kids wouldn’t have the resources of richer kids to get their own arrows and have them fitted and tuned. But then each kid is stuck with identical equipment and to shoot well, equipment must be fitted to the archer and his/her abilities.

The only way to “weaken” an arrow like the Genesis competition arrow is to increase the point weight, and I am not sure that even that is allowed by NASP rules. The significant factor you seem to have control over is draw weight. If any of your kids are shooting anything less than full draw weight, getting them up to that will help. Also, you can do a little testing to see if there are bigger problems you do have control over. One of the things I see on a lot of Genesis bows are streaks on the arrow shelf and arrow rest. These are little smears of plastic left behind when fletches collide with the shelf/rest. For this reason, you want to clean off those surfaces regularly. A bad loose of the string by a beginner and Whack! there is a new streak. You won’t see it, though, if there are myriad others still there.

So for your really serious competitors, get a can of foot powder spray (it has to be powder). Spray the shelf and rest of their bows and have your archers shoot a couple of arrows. If there are any disturbances in the powder, you have a clearance problem. If you are shooting arrows with press-in rather than glue-on nocks (I think the old Genesis arrows had glue-ons), you can rotate the nock so that the fletch that was hitting no longer hits (since the arrow doesn’t start rotating until it is clear of the bow it is usually the bottom fletch). Re-test and rotate the nock until no more problem. Then make all of the other arrows the same by rotating their nocks into the same position. They make nock rotating tools that have built in guides for just this task (see photo below).

A nock alignment tool. The little notched arm is moved so it touches the index vane only when the nock is correctly positioned.

A nock alignment tool. The little notched arm is moved so it touches the index vane only when the nock is correctly positioned.

Since archers with different draw lengths have different string paths, you will need to test each bow-arrow-archer combination. (Bring lots of rags so that archers can clean up their bows afterward.)

If there are big streaks or the rest is getting hit, check the nocking point height. If the nocking point is too low, they will be launching their arrows “nock low” which is asking for clearance problems.

I do believe that you are allowed to adjust your draw weight, no? Having an arrow that stiff (spine is 0.592˝) would require the bow to be about 40#-45# to be shot correctly at that length, so reducing the draw weight would just make things worse, but turning the bow down just a bit (which changes the string path) may correct for a clearance issue so that may be worthwhile. If there is room to turn a child’s bow “up” a bit in draw weight, that might cure the clearance issue and provide better arrow flight.

 

Leave a comment

Filed under For All Coaches, Q & A

Problems Tuning Genesis Bows

QandA logoI get a lot of requests for help and I am glad to provide what I can. One of my readers upbraided me for this because I have been more than a little adamant that archery coaches shouldn’t “work for free.” So, I am being somewhat inconsistent. There are a couple of reasons I do this. For one, I am still trying to learn how to “coach remotely,” so I embrace opportunities to do that. Second, there is so much need for help in the archery coaching community. The main reason, though, is that people are turning to me because they can’t find the help they need. Not that that help isn’t available in every case but that it has been made hard to find. (I really, really, (really) wish the archery organizations would embrace coach support wholeheartedly instead of the current “train ‘em and drop ‘em” approach.) Until such resources are more widely available I will continue to do as much as I can to help those coaches who seek it.

Today’s topic comes from a reader of this blog who seeks help tuning Genesis bows. Here’s his email:

I’ve been darn near driving myself insane trying to learn to understand and tune a bow, specifically the Genesis.

A little background: I’m Level 2 certified wanting to do level 3. Just having trouble finding a training that’s close and works with my schedule having five kids of my own. I’ve read many of your books and in fact own 4-5 of them as resources for me and our coaches. We have a very large NASP program of 95+ in our elementary school from grades 4-6. We’ve been doing NASP for 5-6 years. We’ve won a team state championship in our second year and some individual championships. I’ve not done anything to the bows except yoke tuning and nock point tying 3/8˝ high of zero on a bow square and the occasional serving repair at the local archery shop. Perhaps I should be tying the nock even higher.

I’ve talked to other coaches and have picked up a few tips/suggestions regarding bow tuning and done far too many hours of research. Most coaches, since we’re competing against them, I believe are a bit guarded about sharing too much info. However, it seems almost all of our bows make arrows kick to the left for a RH archer no matter what I do.

For bows that seem to have cam lean I’ve tried rotating the bottom limbs, fiddled with the ATA length by twisting strings/cables, and replaced bushings in the cams. Regardless, I still see arrows kicking typically.

I realize that when pairing archers with bows that are not their own in a program it is not a one-size-fits-all situation. However about 50% of our archers have their own bows and I’d like to be able to tune them properly but cannot figure it out.

Also, once we begin shooting as a team we have enough bows for those who don’t own their own bows to each use one of ours thereby allowing us to individually tune. As NASP has grown it’s become more competitive and I’m wanting to keep up but feel we’re being left behind and want to keep our kids competitive and give them every chance possible to win. I’m willing to do whatever it takes we just don’t know what that is when it comes to bow tuning for the Genesis. If you understand these bows I’d be willing to pay you good money for a private bow-tech clinic if you’re ever in the area, not joking. 🙂

I just read the below link where you mention attaching a guide to bow and arrow fitting to the article regarding but don’t see the text document mentioned. Perhaps it would help. https://archerycoach.wordpress.com/2016/03/03/porpoising-and-fishtailing-follow-up-and-the-acg/

Any guidance or assistance is greatly appreciated!

And here is my response:

* * *

The document mentioned in that post was attached to the email sent to the correspondent, not the post. I have attached it to this email in the hope it might assist you.

Everything I am going to say from now on applies to right-handed bows. If you are dealing with a left-handed bow, you have to switch left and right. ;o)

Your kids arrows are flying to the left and you can’t tune it out because the arrows are too stiff. The “Genesis formula” (my term) is to make a bow and arrow combination that can be shot by a great many people. So the bow has zero letoff, which allows it to be shot by people with widely different draw lengths with no adjustment (not so with a bow with letoff) and an arrow that is too long and too stiff for people with short draw lengths so that it will be long enough and not too weak for people with longer draw lengths. But arrows that are too stiff for a particular situation will fly off to the left. Arrows that are too weak, will fly off to the right. (Remember that left and right directions have to be switched for left-handed archers.) Since most youths fall into the shorter draw length category, most arrows used for the Genesis (especially the “Genesis Arrow” are too stiff and will fly to the left no matter what you do to the bow.

This is because the farther you draw a bow, like this one, the more energy is stored in the bow. The more energy stored, the more energy is given to the arrow when shot and the stiffer the arrow needs to be to receive it. (Imagine a whippy thin arrow being shot from a very stout bow–the arrow might break upon release!)

“So, in tuning, we set up the bow and tune the arrow.”

So, in tuning, we set up the bow and tune the arrow. (Little tweaks of the bow may take place for fine tuning purposes, so this is just a generalization.)

The hard thing with kids is that they are still growing. If you fit them for arrows (see attachment) “correctly” they will over the next six months, grow an inch or half an inch and their draw length goes up accordingly and now they arrows are too short (for safety) and too weak (as the bow is now “stronger” because it is being pulled farther). What we recommend is to fit arrows to youth’s bows that are one spine group stiffer for each extra inch of length you choose. By choosing to use an arrow that is 2-3 inches longer than usual, if you didn’t choose a stiffer shaft, the arrow would be too weak. But with those stiffer shafts, when the youth grows and needs a stronger arrow, that extra length allows the arrows to be shortened (making them stiffer) while still being long enough for safety.

Standard bow setup for “fingers” shooters is to have the bottom of the top nock locator 1/2” above square. The purpose of this is to launch arrows a bit “nock high” to avoid clearance issues with the arrow rest. Genesis bows are not what one would call high precision bows, so some cam lean and other less desirable attributes are to be expected and really don’t contribute to your issues. The problems you are having are likely due to just arrow shaft stiffness mismatches.

I hope this helps.

Steve

PS We are working on a series of e-booklets explaining all of this and the attached document is to be part of that, from which we expect to make a little money ($1.99 per booklet?), so I ask that you don’t share the document SMFAwith your colleagues. Of course, if you learn the knowledge provided in it, you will be free to share that with your fellow coaches. ;o)

PPS We have done bow maintenance and tuning workshops before and we might be able to set something up if you would like (we are not so far from one another geographically). There are, however, people in your community who might be able to provide this service cheaper (we need to recover travel and lodging costs, etc.). The purpose of this e-booklet series mentioned above is to provide much of the information you need. I also strongly recommend the book “Simple Maintenance for Archery” by Allan Anderson and Ruth Rowe. It contains step-by-step instructions for many of the tasks need for tuning and maintenance (with photos!). It is now out in a second edition (photo is of first edition).

Leave a comment

Filed under For All Coaches, Q & A

One More Time (Arrow Tuning While Changing Draw Weight)

QandA logoI got this question as part of a larger issue from one of my Olympic Recurve students:
My Arrow cut length is 29.25˝, so if I buy these new shafts should I cut them at 30.5˝ for now? Or should I cut them at 31˝?”

This student is working his way to a higher draw weight but wants to explore different arrows at the same time. Here’s what I said (with slight modifications).

* * *

My standard recommendation is to make the draw weight change first, then fit yourself for new arrows. (Shooting to accustom oneself to a higher draw weight can be done blank bale and need only take weeks or at most a few months.) But the question here is basically: How do I fit arrows to allow for a higher draw weight in the future? So, that’s what I will address.

apple-arrow-saw

An arrow saw. This one is made by Apple.

A start is to fit your current draw weight and cut length in the new arrow’s spine chart. Then move up one spine group on the chart (stiffer) and then add 1˝ to the cut length or move up two spine groups and then add 2˝ to the cut length. It all depends on how much draw weight you want to add. Roughly 5# = 1˝ of cut length, so if you are looking to go up five pounds, then you need just one spine group and one inch of cut length more than you are shooting now to allow for that change.

This is based upon how spine charts are set up by the manufacturers. They basically define spine groups, defining them by each inch of shaft length or 5# of draw weight for recurve bows. (There are some variations in the draw weights; Easton just made significant changes in their target recurve chart draw weights, for example.)

By buying an arrow that is stiffer, then cutting it longer you can create an arrow that is the same spine as the shorter weaker shaft that would be an exact fit. This arrow will shoot well and as you crank the draw weight up, you can shorten the arrows as you do so, keeping them reasonably well tuned. If you go up five pounds of draw weight and cut off that extra inch of shaft length, you have an arrow that is one spine group stiffer which is required at that higher draw weight.

Longer arrows than needed can also stretch the usable limits of a riser-attached clicker. While such changes are being pursued, using a clicker attached to one’s sight extension bar may be helpful. When arrows are cut shorter, the clicker needs to be moved in the exact amount of the cut.

This is a lot of fussing, but the advantage is this: it is very hard for archers to ignore where they arrows land. If one is shooting an untuned bow, the arrows will not group well and the archer will often think it is because they are doing something wrong and change their behavior for no reason other than their bow is not tuned. So having a reasonably tuned setup at all times can be beneficial.

 

Leave a comment

Filed under For All Coaches, Q & A

Porpoising and Fishtailing Follow-up … and The ACG

QandA logoThe issue regarding bad arrow flight in the last post was not completed addressed, so the discussion continued:

Thanks so much and I loved your blog post. Glad we could help with the question. I looked at my bow and noticed that I did have a lot of scuff marks on my bow. I do have a bow square and I checked mine and some of the students and noticed that especially mine was less than 3/8” right now. I cut my indicator off and retied it as you suggested and I noticed I was getting more direct flight and more 10’s. Now, I will have to test more over the weekend because my serving string started to unwrap and so I need to get all that fixed. So, I will retie the nock indicator again and clean off those scuff marks as suggested.

I am also searching for answers as to why at 10 meters our students can hit consistently in the 9-10 rings but when they move back to 15 meters its like they are shooting from a mile away. The arrows just scatter everywhere. I really think right now it is in their heads.

* * *

To which I responded:

NASP uses Genesis bows and arrows exclusively.

NASP uses Genesis bows and arrows exclusively.

In your case, your nocking point position is tunable. The first level of tuning is usually through the bare shaft test. You want the bare shafts to hit just below and just to the left of fletched shaft groups. (The “below” part is adjusted with your nocking point location. (This presumes you are right-handed and using a bow sight. If you are shooting bare bow, there is less of an effect.

One of the ways to ease the transition from shooting at 10- to 15-meters is to up the target size (from 40cm to 60cm or 60cm to 80cm would be proportionate). Then when comfortable at 15m you can drop the target size and see what happens. Normal this scenario comes (IMHO) from the drop in performance caused by the extra distance resulting in “trying” which is not desirable, especially since the “trying” becomes: try this, try that, try … maybe this, etc. The need is for them to preserve their form when changes occur.

* * *

As usual, one thing leads to another . . .

In our competitions we are not allowed to use sights and we must use fingertip release. We have tried shooting bare shafts but I might not understand the concept. We shot three fletched arrows last night and two bare shafts and the bare shafts were all over the place. They would fly straight until about 2 meters from the target and then usually fly upwards and go in the target at the top at an angle.

The idea I assume is that if you have proper form you will be able to shoot bare shafts almost as well as fletched arrows?

* * *

And then I said . . .

Correct, but if the arrows are hitting so high, the nocking point must be very low (or there is some collision of the arrows with the bow (called a “clearance problem”).

Adept archers shoot bare shafts out to 70m and beyond. The fletches are only needed to correct for slightly mis-launched arrows.

When you shoot off the point (you are aiming off the point, no?) the position of the arrow is fairly constant (line of sight has arrow point and point-of-aim in it and your anchor fixes the back end of the arrow in space, under your aiming eye), so any change in nocking point location merely changes the position of the bow vis-à-vis the arrow. This compensates for a great deal of other things being somewhat “off” which doesn’t happen when a sight is used. (I know that NASP doesn’t allow sights, but you referred to “your bow” and you are not so limited.)

You can tune your arrow flight, that is make changes until the arrows fly well, but it is probably the case that the spine mismatch (arrow v. draw weight/length) is probably so severe you can’t get any kind of decent arrow flight with bare shafts.

Try raising your nocking point and trying again.

This is where “ordinary” archery and NASP run acropper of one another. The fixed bow and arrow combination cannot possibly work well for all and really is somewhat of a wonderment that it works for any. There is a major transition that all archers go through early in their archery practice and that is acquiring their own equipment. When this is done properly, the archer is “fitted” with the right-sized bow and arrows and then the equipment is tested and adjusted to be “just right.” I have attached a guide (just the text, actually) about “bow and arrow fitting” for you if you are interested.

* * *

Since the Archery Coaches Guild is now up and running … and is now FREE(!) … many of you may want to go over there (www.archerycoachesguild.com) and sign up and Join the Conversation! We need people to post questions, favorite coaching tips, etc.

1 Comment

Filed under For All Coaches, Q & A

Sources of Inconsistency, Part 3

Note If you haven’t read parts 1 & 2 yet, please do so, it will make this more understandable.

So, my student and I found some time to work together this past weekend and to make a long story short: mystery solved (we think).

The issue is a lack of consistency indicated by a drop in scores on the NFAA indoor 300 round (60 arrows, 5-1 scoring) from the 270-280 range to the 240-250 range which had to have a cause. In all such cases, there is the question: “Is it me or my equipment?” So, my student took his backup bow to league just before the lesson and shot a score in the 250s, so we know that the problem wasn’t based entirely in the equipment.

But a sound approach is to remove all of the equipment issues first as it is then easier to focus on the form/execution issues with the bow giving good feedback. After shooting some to warm up we did a bare shaft test (three fletched, two bare) while I watched his arrow flight. There was definitely some poor arrow flight involved in the vertical plane and the bare shafts were higher than the fletched group. So, the suspect was a “too low nocking point;” measurement also indicated that it was on the low side (and the nock locators were too easily moved, which was likely the source of the problem). We replaced the top nock locator, tying on a new one with each loop cinched tightly. (This keeps the locator from moving until it is glued down or turned on purpose.) This locator was moved up by about one-eighth of an inch compared to the old one. A retest showed the bare shafts grouping and closer to the fletched shafts (but still slightly high) with the arrow flight improved. We could have continued in that vein but there was something else: a form issue.

At full draw my archer’s shoulders were slightly tilted (front shoulder high). This can happen even to the most serious archers who also have real lives. Family and work intrudes upon our archery and we lose focus and continuity. By this I man we have a mental and/or physical break from practicing our good form. Slight changes drift in and are accepted as normal. As I watched, the subtle shoulder tilt was causing his draw elbow to move as much down as around during followthrough. This, I suspect, is also a contributor to the high bare shafts. If the shoulders are tilted, the drawing forearm is out of line with the primary force line (PFL) we desire. In this case, it is below. This changes the angle the draw hand and fingers make with the bowstring (slightly) causing the string to be pulled a little more down, in this case, rather than just back along the PFL. This cause shots to go high.

So, I asked my student to thrust his “away” hip back and to exaggerate it. His first attempt got his torso vertical, his shoulders level and his arrow into the X (just luck but bolsters coach’s reputation in any case). My student reported that he though he had pushed his “away” hip a great deal whereas he had moved it only a smidgeon. This is a phenomenon reported by both golf and archery coaches, “you have to ask for a lot to get a little.” (This one is going into Volume 3 of The Principles of Coaching Archery!)

We therefore devised a little experiment. He has a mirror set up where he shoots at home to check his posture. With a vertical tape line or a plumb line hung just in front of it he is going to work on getting his spine plumb and his shoulders level. Then we are going to recheck his bare shaft test. This may well get us a perfect test and no further adjustment of the nocking point locators will be necessary. If not, then additional nocking point tuning is needed. When this is all done, I think this student will be back to championship level form.

To Summarize

It is not uncommon for a small flaw to creep into an archer’s form. Elite archers have to practice many days a week to ensure that this does not happen, and then it even happens to them from time to time.

Competitive recreational archers face all kinds of distractions: job/school changes, significant other changes, births of children, etc. All of these are opportunities for their form to become different. Since we all age and change with age, such time related differences are to be expected and the others just fit into this normal trend. Very good archers experience only small changes but because they expect relatively good scores, these still show up on their score sheets.

The issues involved are what I call “Bell curve” problems. If you take any parameter of form, execution, or equipment, you will find there is a range over which its setting provides optimal performance. In this case, nocking point location” like brace height or any other parameter would show this behavior:

Tuning Graph (150 dpi)If the nocking point is way too low, we would get very poor performance; at just to little too low, we would get something better but still poor; at just a tad low we would get good performance. Spot on would give the best performance; slight higher would cause the performance to fall off a tiny bit and the farther it got in the “too high” direction the worse things would get. We have just described a performance hill (a bell-shaped curve). Some parameters have more than one such hill (as alluded to in the diagram). Nocking point location probably has just a single hill and single hilltop. The center of that hilltop is where we want to be. The reason for this is the tops of those bell curves are relatively flat. If you have a slightly flawed execution, such as pulling down or up on the bowstring when the arrow is loosed, you subtly change the actual location of the point in space the arrow comes off of the string. If the fixed position of your nock locators, though, puts you in the center of the performance hilltop, a slight shift one way or the other doesn’t affect performance all that much. But, instead of being “top dead center” you are at the edge of the top (left or right, high or low), a slight change in another parameter can produce a relative large loss of performance.

In this case, a combination of a too low nocking point (a relatively recent change in the equipment) combined with a slight shift in form brought about a 20+ point drop in 300 round score. I suspect that the shoulder problem was there first and then when the nocking point locator moved … ooops!

What to Do In order for an archer’s equipment to be in order, they must tune it by shooting (and they can’t tune any better than they shoot) so the two are intertwined. When they achieve a stable state for their equipment and are shooting acceptable and consistent scores, they must document the heck out of their rig. You should insist on this. (I have a form I email to my students for this purpose. If you want a copy, send me an email at steve@archeryfocus.com asking for one and I will send it to you.) Having this record means that when things go wrong, you can measure up their rig to see if anything has gone wrong. (Some of these things are invisible (cracks in interior limb laminations, broken threads of bowstring material under the center serving) and may show performance effects before measurable manifestations of them show up. But these are rare.)

If you can correct any equipment flaws and the problem goes away, much the better. If it does not, then you must look to the archer. It is not uncommon for the problem to have multiple causes as did this one (I think).

Oh, did I mention that leveling my students shoulders (subtly) required his clicker to be moved? We moved it out about an eighth of an inch, later it will need to be refined. Shifting shoulders up and down, even subtly, affects draw length. All such changes go straight into the archer’s notebook to document them.

If you change one thing …

2 Comments

Filed under For All Coaches, Q & A

Point Weight Woes

QandA logoI got an email from a friend regarding a problem you may have encountered in your coaching. Here it is.

Hi, Steve!
I wanted to bounce something off of you if you have a moment. I had some unexpected issues with arrows over this past weekend when I was shooting my first FITA. I was struggling much more than anyone else with the light wind we were having. Right before the competition, I had been trying to tune in my new arrows that were acting too weak and I ended up reducing the point weight to 90 grains, which had them finally performing well in practices. I put up some personal best practice scores with my adjusted arrows right before the FITA round and was feeling good about my performance. I suspect, though, that the light point weight was my downfall and part of what was giving me such problems. My longer distance scores were the worst I’ve ever done in my life, however my shortest distance score (30m) was right on the money with my normal practice scores, even though the wind was the same and I should have been the most fatigued and dropping points at the end.
            I bought my arrows slightly long and am thinking about cutting off a 1/2˝ and putting 110 grain points back in the shortened arrows. My theory is that that will have a similar effect as having the longer arrows with lower point weight, but will give me more ability to cut through the wind. However, I can’t find any literature online or in my many archery books about point weight vs. arrow length in trying to make adjustments to arrow spine. Which is a better adjustment to make, and is there any such equation such as “each 1/2˝ of length = 20 grains of point weight” or whatever? I’m not keen on cutting down my arrows if that might not give me the results I’m looking for.
           
Thanks in advance for any help or advice you can give!

* * *

I doubt your point weight made all that much difference so it may or may not have been the source of your woes.

First I have to ask: when you were tuning in these arrows, did you have a reasonable centershot, plunger button resistance, nocking point height, and was your aperture centered above your arrow? If not, you were tuning to a less than optimal setup. It is always important to have a bow in a proper setup when trying to tune. If your aperture is off center, for example, you are then trying to tune your arrows to a dynamic spine that will compensate for a mis-set sight!

Most Olympic Recurve archers have a FOC balance point of 13-15%, so that is something you might want to check. (FOC guidelines are the equivalent of the “equation” you desire.) The vast majority of OR archers have 100 gr points (110 gr being in second place, I think), unless … you are shooting a very lightweight all-carbon arrow such as McKinney IIs, then 90 gr and even 80 gr come into play.

As far as wind stabilization goes, there are two strategies: use a heavier arrow (like Easton X10s) or a lighter arrow (like Carbon Tech McKinney IIs or Carbon Express Nano Pros or Medallions). The heavier arrows have more mass and therefore require more wind force to move them (inertial stabilization). The lighter shafts are faster and hence spend less time in the wind for the wind’s forces to act on them (speed stabilization). When an arrow is shot long distance, a higher FOC is generally desired to keep the arrow on track during those longer flight times. When I was shooting field archery a lot I was using 60, 70, and 82 gr points in very long arrows with little downside. But shooting FITA rounds, I was using 100 gr or even 120 gr points (again, in very long shafts).

So, research Front-of-Center (FOC) balance and how to measure it (it is easy) and check your current arrows. If you are close to 13-15%, then it was not your point weight that was a problem. If it is 6-9%, then maybe so.

If it was not your point weight, I suggest you go back to a basic setup and retune (nocking point height 1/2˝ above square, centershot has inside edge of arrow point visually lined up with outside edge of bowstring with string centered on the riser (visually), plunger pressure mediumish, aperture centered above arrow when bow is vertical (I just run the aperture down to the bottom of the sight bar and eye-ball it)). Also, you need to take off all vibration absorption devices (Doinkers, et. al.); they can only mask the feel of good shots.

You may find that the tune you had wasn’t all that good.

The reason the tune is so important is the tune establishes the launch angle of the arrows (at what ever angle the bow is being held), so if the centershot is way outboard, for example, the arrows are launched point left. Then the fletching has to correct for that, but if the wind is blowing more than a bit, that “sideways” launched shaft is going to be blown in unpredictable ways (the shaft itself is a bigger source of drag than the fletches) and you are going to have very large groups as a consequence.

I hope this helps!

Steve

Leave a comment

Filed under For All Coaches, Q & A

Beyond Barebow Basics

I have been working with one of my Barebow Recurve students on his full-draw-position in order to assure he could get “in line,” that is have a good full-draw-position, one that exhibits the Archer’s Triangle. This has necessitated a different anchor position (hand on face). Here is a report he sent me yesterday:

Dear Coach Ruis,
With my new anchor point, I have had several problems I am unsure how to address. First, my arrows are flying much more to the right because my new anchor is farther to the left on my face. I now have to aim in the black, left of the yellow, to get the arrows to land in the yellow. Second, my string is now so far from my riser that it is impossible to align the string up to the riser. Third, my new anchor point isn’t as unique as my old one. Sometimes, I get arrows that fly high because I overdraw and I’m unsure exactly where to place my hand.
Thanks

***

Obviously your new anchor point is different and will feel “funny” but maybe some further experimentation is necessary. Maybe you haven’t found your “new” anchor point yet.

A couple of additional things:

Nobody every cut their nose with tied-on anchor points. (He was using brass nock locators that rubbed against his nose and which had burrs on them from the use of inexpensive nocking point pliers. SR)

You might benefit from moving your nocking point locators up higher than we discussed. (The 0.5˝ above square is the starting point for non-stringwalkers.) Brent Harmon and I did a preliminary study (note the “preliminary,” this is not gospel) which shows that instead of walking your fingers down the string from a “normal” nocking point, if you walk the arrow up the string (by moving the nocking point), you need less of a crawl. Obviously this would be problematic for outdoors as so many different crawls are used, but indoors there is basically only one crawl.

While I wouldn’t do anything to your arrows just yet, your comment “I now have to aim in the black, left of the yellow, to get the arrows to land in the yellow.” indicates your arrows are behaving as if they were too stiff. (The archer is left-handed. SR) A change in anchor and full-draw positions is also often a change in draw length which can affect the relationship of bow with arrow (vis-a-vis dynamic arrow spine). So, find your new anchor, one that is repeatable and “findable” (“comfortable” will come with repetition) then retune. (One way to deal with too stiff arrows, if they stay “too stiff,” is to increase bow weight—it may only require a turn or two on your limb bolts since you were tuned fairly well before.)

Regarding your “string picture,” this is a consequence of your head position also, not just your anchor position alone. At full draw, focus on your string position and then reposition your head slightly until you get a decent string picture. Your head should end up straight up and down, just turned on your neck to see the target. Very, very slight movements of your head (typically rotations, not tilts) will change your string picture significantly. Find a good one. String picture is a way of ensuring head position (in particular, of the aiming eye) and can be used to adjust for side winds, so people can and do adjust it on the fly.

A “unique” anchor position for your string hand is of no value if it doesn’t allow for all of the other aspects needed for strong shots. A unique anchor position for a tilted head (which negatively affects binocular vision and depth perception) is not a good trade-off.

Let me know what is working.

Leave a comment

Filed under For All Coaches, Q & A