Tuning a recurve bow

[James Park]

From the many queries I get on tuning a recurve bow:
(Covered in more detail in "Mastering Bow Tuning", as is tuning a compound bow).
Assumptions:
- The bow's physical length is about correct for your draw length.
- Adjustable limb alignment.
- Adjustable draw weight.
- Arrows of a size that will work.
- The arrows are about level with the back of the riser when at full draw.
- You have a sight and a clicker.
- You have a good bowhand position and are not twisting the riser.

If your arrows are the correct size, the following process is easy, fast, accurate and repeatable.

Steps:
- Select the correct string length. This should ensure that the correct amount of string is sitting around the recurve on each limb. It is best to use the manufacturer's recommended brace height.
- Set the tiller. Make the top tiller about 1/8" greater than the bottom tiller.
- Align the limbs. You need to end up with the string running centrally down the limbs and the riser, and for the riser not to be twisted off to one side.
- Set the pressure button so that there is zero movement (I put a match in it). Then adjust the centreshot so that the arrow is sitting exactly on centre.
- Shoot some fletched and some unfletched arrows at about 15-20M. Adjust the nocking point so that the fletched and unfletched arrows hit at the same height.
- Adjust the bow's draw weight so that the fletched and unfletched arrows hit the same place horizontally. Note that if the arrows are not the correct size, this step will not be possible, and there will be little you can do to fix it (sell the arrows and buy new ones - with a recurve bow you really do need to get the exact correct size, one size wrong will not tune correctly even with much frustrating tinkering). If the bow draw weight will not go high enough you can try a lighter string. If the bow draw weight will not go low enough you can try a heavier string.
- Still with the solid pressure button, adjust your sight so that you are grouping around the centre of the target.
- Now, do not change the sight setting. Take the match out of the pressure button and adjust the spring tension to "something nice".
- Now that you have some give in the spring, you will need to push the arrow out a little from true centreshot, so adjust the pressure button position.
- Shoot some arrows and see where the centre of the group is. If the arrows are to the left then move the pressure button to the right, and vice versa.
- Shoot some fletched arrows at a longer distance and check that they seem to be flying well.
- Powder test to ensure that the rear of the arrow is not striking the rest or pressure button.
- It should now be working pretty well.

Note that we are not fiddling with the spring tension to try to get the fletched and unfletched arrows to group together. It does not work like that. The key adjustment is changing the bow's draw weight.

Note that we tune a barebow recurve in essentially an identical manner (using a sight and a clicker).

Note that we tune a compound bow shot with fingers in an identical manner.

[Marcus]

I tuned up Jessica Walters bow using Jim's method over xmas and she stepped out with it fresh and shot a 324 at 50m on a small face.
I have tuned a number of recurves using this method and the traditional hit-miss method and Jim's is faster and alway produces great arrow flight and good groups.

[gt]

The US coach Dick Tone (of Cavalier) has used and publicized this method for more than 30 years. With all due respect to Jim, I don't think it's exactly news.

(It seems a lot of people have published this in various places without giving any credit to Dick.)

[James Park]

gt,
Yes, agreed, same as used by Dick Tone (and important to note his contribution, as you say).
(I also used it back in the early 1970's, having thought back then about the physics of what happens to the arrow).

[TJ Mason]

I can certainly vouch for this method. It gets the bow matched properly to the arrows, and builds in a good deal of

[Sandy Hancock]

- Shoot some arrows and see where the centre of the group is. If the arrows are to the left then move the pressure button to the right, and vice versa.

Just to clarify Jim: are you saying to adjust the centreshot (ie move the static resting position of the button) or adjust the spring tension (ie the "dynamic centreshot")? The quote above suggests the former, but I suspect you meant the latter....

[James Park]

Sandy, I meant the former, that is: adjust the position of the pressure button.
You could also adjust the spring tension, but I think adjusting the position is easier and faster. It also avoids problems of sometimes having archers end up with very weak spring tensions and the button bottoming out.

[Sandy Hancock]

Sandy, I meant the former, that is: adjust the position of the pressure button.
You could also adjust the spring tension, but I think adjusting the position is easier and faster. It also avoids problems of sometimes having archers end up with very weak spring tensions and the button bottoming out.

So if you then powder tested and found contact, would you suggest changing the spring tension and then readjusting the centreshot to bring the group back to the gold?

[James Park]

Sandy,
Yes.
Assuming you have an arrow that is appropriately matched to the bow, contact is most likely to be around the arrow's rear node (about 150mm from the nock, or thereabouts). The rear node does pass very close to the rest and button, and contact there is the most difficult one to deal with.
If it is contact with the fletches and everything else seems ok, I would try rotating the nock a little.

[redline350]

I have a question some say for a 68in bow that you should have it 6in shorter that the bow others 3in. Could some one help me to confirm the theory so I can order a new string.

[Progen]

I have a question some say for a 68in bow that you should have it 6in shorter that the bow others 3in. Could some one help me to confirm the theory so I can order a new string.

No one can give you a definite answer unless you supply your limbs and riser combination and their lengths at least. Basic rule of thumb from some sources say 2 1/2 to 3 1/2 inches shorter than the bow height / length. However, that also depends on the type of string material you're going to order. If say, you're going to order something that will creep and creep and creep and also has some stretch in the bargain, like Angel ASB Dyneema, then you would only go for perhaps 2 to 3 inches maximum. The guy who makes my strings from this material makes my strings at 64 1/2 inches.

[James Park]

As I remember it, a 68" bow is defined as a bow requiring a 65" string.

[redline350]

Hi Guys,

Thanks for that information, at times you ask archery shops you can get more confused and then end up with the wriong thing. I thought I would do some research and try for myself, so I have paid for will try this saturday.
redline350

[Betty-Anne]

Hi Guys,

Thanks for that information, at times you ask archery shops you can get more confused and then end up with the wriong thing. I thought I would do some research and try for myself, so I have paid for will try this saturday.
redline350

You should talk to Apexrob (Mr Bling Strings) His strings are spot on!

[GrahameA]

Redline

Have you considered making your own strings??

[Betty-Anne]

Redline

Have you considered making your own strings??

Back in the OLD days when we used Kevlar for strings and said strings were excellent but only lasted for about 1000 arrows, we were all really good at making strings. But these days I figure that there's not a lot of point when strings last a long time and there's someone out there who can make really good strings for a very reasonable price.

[StevenB]

Back in the OLD days when we used Kevlar for strings and said strings were excellent but only lasted for about 1000 arrows, we were all really good at making strings. But these days I figure that there's not a lot of point when strings last a long time and there's someone out there who can make really good strings for a very reasonable price.


sure its nice and easy to buy strings, but it is still a skill worth learning. Especially if you have the time to make them yourself save a little money

[Win for won]

- Powder test to ensure that the rear of the arrow is not striking the rest or pressure button.



Whats a powder test?:???:

[Progen]

Whats a powder test?:???:

Where you sprinkle some form of powder around the arrow shelf / cutaway area to see whether your fletches clear the rest / riser cleanly. Streaks in the powder usually indicate clearance problems. What kind of powder you use is up to your personal preference. Angel dust has often brought good results. :D :D :D

ps. Most folks use talcum powder.

[James Park]

For a powder test, I wet the back 1/3 of the arrow on the side that passes by the rest/launcher and sprinkle powder on it (tap the arrow up and down on a piece of paper with some talc on it). Then shoot the arrow and see if any of the powder has marks in it.
(There are some pictures in "Mastering Bow Tuning").

[Progen]

For a powder test, I wet the back 1/3 of the arrow on the side that passes by the rest/launcher and sprinkle powder on it (tap the arrow up and down on a piece of paper with some talc on it). Then shoot the arrow and see if any of the powder has marks in it.
(There are some pictures in "Mastering Bow Tuning").

Ok, so this method means that you'd like to see whether the arrow rest / riser is contacting the shaft then. Did I get that right? Do you wet the fletching as well?

[James Park]

Yes, definitely the fletching.
For a recurve bow we are mainly looking for contact in two places: near the arrow's rear node, and around the fletching.

[reversehaven]

Where you sprinkle some form of powder around the arrow shelf / cutaway area to see whether your fletches clear the rest / riser cleanly. Streaks in the powder usually indicate clearance problems. What kind of powder you use is up to your personal preference. Angel dust has often brought good results. :D :D :D

ps. Most folks use talcum powder.

wait. streaks in the powder? are you saying that the whole rear 3"(or so) of the arrow (including the fletching) should clear the riser and the plunger totally?

like i did a powder test once. there was one consistent streak right in between the two non index fletches (or off-fletches) of each arrow. does that mean that my arrow doesn't have sufficient clearance or is it all right?

by the way, isn't the bottom index fletch supposed to hit the arrow rest just a bit as it exits the riser?

hmm i'm still exploring this relatively new area on clearance. never really had any solid guidance on this area so i'm just asking to clear my doubts.

[James Park]

Aside from contacting the arrow rest and launcher around the arrow's front node (which is essential), it is necessary that no other part of the arrow makes any contact at all.

[Doctor_Eyepatch]

on the subject of letting the fletchings clear the arrow rest, ive read this can be done by putting the knocking point a fraction of an inch higher than the arrow rest, but wouldnt this cause the whole arrow to deflect down into the rest?

[Progen]

Aside from contacting the arrow rest and launcher around the arrow's front node (which is essential), it is necessary that no other part of the arrow makes any contact at all.

Hope James won't mind me adding 'upon release' since reversehaven does get a bit daft at times. :rofl: He might decide that the Air Rest is the ultimate rest.

[James Park]

on the subject of letting the fletchings clear the arrow rest, ive read this can be done by putting the knocking point a fraction of an inch higher than the arrow rest, but wouldnt this cause the whole arrow to deflect down into the rest?
That would be for a compound bow. For a compound bow, how the arrow flexes and whether or not it hits the launcher depends on quite a few things (for example, on the flatness of the nock travel).
My comments on this thread have been for a recurve bow.

[Doctor_Eyepatch]

ok, i shoot recurve and i was a little unclear on doing the knocking point.
thanks mr parks! :)

[Brocky]

Hi Jim after you tune your bow using this method do you then proceed to fine tuning the bow & if so what method do you use.

[James Park]

After tuning the bow that way I have not found it necessary to do anything else. I do watch how the arrows fly at about 70M as a final check.

[Progen]

Standing by James on this one. Tuned using the method he brought up and have found no need to fine tune at the longer distances. Just did 70 metres yesterday. Lovely!!! No need to do all that horrible walkback thing. :mad: :mad: :mad:

[Sandy Hancock]

Agree with Progen. I just retuned today after fiddling around with my stabilizers.
After doing Jim's basic tune I went out to 70m. Bare shafts were flying dead straight, within the (significant) limitations of my ability. As with any method, the better you shoot, the finer the tune will be.
Now I just need to tune the archer a bit better ;)

[TJ Mason]

What firmness of pressure button did you guys end up with? I got a fairly soft button (softest spring that Beiter provides, wound out one turn from the mid point), but other people tell me they got quite a firm button.

[James Park]

Regarding button spring pressure:
In the method I have described, you can set it to whatever you think feels nice, the method then takes care of it.
One problem of setting it too soft is that the button can bottom out when you shoot, so too soft is not good.

[Sandy Hancock]

Yeah. What Jim said.
Use the centreshot adjustment of the plunger rather than the spring tension. The two variables are complimentary, so you can achieve the same effect by altering one or the other.

[Progen]

Regarding button spring pressure:
In the method I have described, you can set it to whatever you think feels nice, the method then takes care of it.
One problem of setting it too soft is that the button can bottom out when you shoot, so too soft is not good.

I know it sounds rather vague but that's it. :D Just dump in whatever spring you have, something that's somewhere in the middle. Neither too hard or soft. Something that has some give but not too soft that your shafts hits something on its way out resulting in poor clearance. With my Shibuya DX, I put in the softer spring, turned the little allen bolt in the center somewhere in the middle but I wound the knob or whateverytheycallit all the way in so that if it ever loosens, I'll simply have to wind it down all the way instead of wondering which position was it previously.

This method saves you heaps of time, Mason. Lovely!

[Progen]

Oh, I do have one question for Mr Park (he does sound Korean when you address him like that, doesn't he? ;) )though.

The arrows are about level with the back of the riser when at full draw.

I'm using the longest clicker plate on my Aerotec with a Cavalier magnetic clicker. The clicker rod is angled and rests against the very edge of the clicker plate. This means that my arrows are about 1 inch from the very back of the riser. Will this cause me any inconsistencies in tuning results or any other disadvantages?

I used to shoot about 1/2 inch longer when I was mucking around with form changes but I'm pretty much settled on that now.

[James Park]

I think that the location of the front node of the arrow is of importance. If the arrow is a long way out in front then the front node will possibly be forward of the pressure button to start with. I would prefer the front node to be about level with the button after the first 1/4 cycle of flexing (when the arrow is straight). Hence my comment that I prefer the point to be about level with the back of the bow.

[Progen]

Oh ok. Cheers. Current setup shoots fine though but I still have some play in my tiller bolts so perhaps one day when I have nothing to do, I can have a bit cut off the shafts and the bolts tightened down to give me an extra pound perhaps.

[alexvpaq]

Agree with Progen. I just retuned today after fiddling around with my stabilizers.
After doing Jim's basic tune I went out to 70m. Bare shafts were flying dead straight, within the (significant) limitations of my ability. As with any method, the better you shoot, the finer the tune will be.
Now I just need to tune the archer a bit better ;)

:mad: I got a lot of tuning to do :rofl:

[The One]

Jim, why do you set the bow up for exactly centreshot with a stiff button? Will there still not be a force exerted by the arrow on the button, causing the arrow to still come out of the bow at a slight angle?

[James Park]

The end result is that the arrow comes out on true centreshot.
Yes, it does push on the solid button, but still comes out on centre.
If it does end up a bit outside centre that is ok. But we don't want it inside centre.

[STRINGWALKER]

JP can you tell me the max arrow diameter you can use for Fita field, is there a formula.
Thanks

[James Park]

JP can you tell me the max arrow diameter you can use for Fita field, is there a formula.
Thanks
The maximum permitted by FITA is 9.3 mm.
I use which ever of my arrow types are grouping the best and for which I have excellent sight settings. Hence, quite happy to use my X10's or FMJ's.

[STRINGWALKER]

Thanks, please ignore PM.

[TrevorK]

I try to set up as instructed, at 20M flecthed shafts grouping well and bare shafts are approx same height, but left by about 6"-8" this was just by adjusting nock point. wound up poundage and still the same. My understanding is that bare shafts would never hit the same point as fletched, ie less drag and lack of steering on bare shafts! your thoughts

Trevor

[Aechmea]

I have a Hoyt Protec / XT3000 limbs with Lightspeed 500 arrows. And shoot with fingers.

I was always suspicious that the arrows were leaving the bow less than perfectly.

I tried the Park tuning method last month (maybe it was the month before). Unfortunately the result was that no matter what spring or centre-shot setting I used, the bare-shafted arrow swerved to the right like a banana. This indicates that the shaft is too weak.

I then went back to re-evaluating spine using the Easton charts. I found that my arrows are too weak by about 2 groups. So I am therefore eagerly awaiting new 400 series arrows, but I am desperately interested in pursuing a proper tune so that my arrows leave the bow in a somewhat straight direction, without the fletching having to stabilize the flight. At the moment my bottom fletch contacts the support wire and the button on the way out.

The problem was that the arrows were selected without proper regard for length, drawweight, and a for finger release, with too much emphasis placed on arrow mass per pound drawweight. The 500 series arrows are fine for release aid and a 29in length, but not for me.

If you are getting on a bit in age, and prefer a 45# bow, but have a 31 inch draw length and use fingers, then be very careful with your arrow selection. You have to have reasonably spined arrows before you even start to tune.

Now, where are those 400's! They should be here by now!

[James Park]

Trevor,
Unfortunately it sounds like you need a different arrow size (one size different, probably). Best if you can find someone who has some your length but a different size to check.
With a recurve bow, if you cannot get the fletched and unfletched arrows to group together because they are the wrong size there is not much you can do about it.
However, first check that you are not twisting the riser with an incorrect bowhand position (not usually likely with a recurve, but worth checking before new arrows).
When you do get the correct size and draw weight they will indeed group together beautifully.

[James Park]

I then went back to re-evaluating spine using the Easton charts. I found that my arrows are too weak by about 2 groups.
Yes, that would certainly cause a problem, and make it impoossible to tune.

[TrevorK]

James, what do you think then?, #38 limbs, draw lenght 28" and an arrow lenght of 28" and easton say navs 610 are the way to go. Onlyy been shooting a couple of years and can shoot 545 portmouth.

Trevor

[James Park]

Trevor,
I have usually found the Easton selection chart to be pretty reliable. However, if you can check with someone else' arrow first it would be useful.

[TrevorK]

I'll try to, do you feel I should have a stiffer or weaker spline?
Trevor

[James Park]

Trevor,
For right handed, if the unfletched arrows are to the left of the fletched arrows you need to either increase the draw weight or use a lighter size arrow.

[TrevorK]

James, I'm right handed, I'll have another go tomorrow, increasing bow weight, funny though, I thought that I was weak on spine. Post tomorrow my findings. thanks
Trevor

[Sandy Hancock]

I try to set up as instructed, at 20M flecthed shafts grouping well and bare shafts are approx same height, but left by about 6"-8" this was just by adjusting nock point. wound up poundage and still the same.

If you are talking the stiff plunger phase at centreshot, your arrow spine is a little too stiff. A slightly stiff arrow is better than slightly weak. If you want to get the tune *exactly* right you need more pounds or weaker arrows.

My understanding is that bare shafts would never hit the same point as fletched, ie less drag and lack of steering on bare shafts! your thoughts

With a perfectly tuned shooting system, *and very good shooting*, bare shafts will land slightly high due to their higher launch velocity, but will go dead straight.

[Progen]

James, what do you think then?, #38 limbs, draw lenght 28" and an arrow lenght of 28" and easton say navs 610 are the way to go. Onlyy been shooting a couple of years and can shoot 545 portmouth.

Trevor

That's pretty similar to what I'm at. 38lbs at the fingers (limbs rated at 40lbs, I'm a smurf, I know :p ), arrows cut to 27 5/8 inches with 110 grain points. And yes, I'm using 610 Navigators too. They're a bit on the stiff side for now but I still have a bit of play in the limb bolts. You might want to play with going up 10 grains in point weight, Trevork. Should do you some good in arrow flight too.

[Archangel]

With a perfectly tuned shooting system, *and very good shooting*, bare shafts will land slightly high due to their higher launch velocity, but will go dead straight.
Higher launch velocity because they don't have the weight of fletchings?
That's going to be really subtle - I'm not sure what three spinwings and a little tape weigh, but it can't be much.

[puddin]

3 spinwings with tape weigh the same as 1 easton dimond vane so it makes bugger all difference.

[The One]

Higher launch velocity because they don't have the weight of fletchings?
That's going to be really subtle - I'm not sure what three spinwings and a little tape weigh, but it can't be much.

I weighed 3 fletches with the usual amount of tape and sticky tape, but I forget how much it weighed... Maybe 2.6 grains or something? Definately enough at long distances, but hard to differentiate at close distances.

[James Park]

The mass difference due to no fletches will make very little difference at close ranges. At longer ranges it will be more the difference in aerodynamic drag that makes the difference.
Nevertheless, it is best to tune the bow such that the fletched and unfletched arrows group together. Because of the weight/drag differences, this will result in a slightly higher nocking point than would be the case if we allowed for those differences in the heights we tuned them for. This helps to ensure that we do get good arrow clearance with the rest.
That is: ignore it.

[TrevorK]

James, down on the range today. Can't pull any higher bow weight, so reduce to my normal #40 on the fingers, cost of replacement arrows a bit high at the moment. Might try different point weight to weaken my 610's. Got a double FITA on the 11-11, so i just have to go with what I got at the moment. Thanks

Trevor

[Progen]

Out of curiosity, what limbs are you using? Your situation would seem to reinforce my belief that the XQ-1s are fast.

[TrevorK]

Hi, i'm using W&W Synergy Titanium carbon #38 limbs on a 25" W&W Exfeel

Trevor

[TrevorK]

I use normal fletches
trevor

[Progen]

Ok, another question. What I have right now is the sightpin about 1/2 to 3/4" (didn't really measure) AWAY from the centerline / stringline / centershot. I take this to mean that the arrows are on the stiff side but they group fine with the bareshafts at 30ish metres (didn't try at 50 or 90) and the bareshafts still land in the target at 70 metres although they don't group with the fletched ones at that distance.

I'm currently using 120 breakoff points with one section broken off to get me to 110 grains. Thought of ordering another set of 120 grain points and using them complete this time. That should soften my arrows nicely and allow me to move the sightpin in closer to centershot. At the same time, I'm thinking of going down a turn or so on the tiller bolts to up the poundage a bit as well as having the arrows trimmed 1/4" should they end up too soft.

What say you, James?

[James Park]

I would not make the assumption that the arrows are wrong. If the unfletched and fletch arrows group together and fly well, they are probaly just fine and the tune is fine.
Where do you align your string? That would do it. Also, if you twist the riser it would do it.

[Progen]

Don't get me wrong, James. I'm pretty happy with the setup and tune the way it is now. Just that my sightpin's pretty far away from centershot so I was wondering whether it'd be better if I used slightly heavier points to soften up the shafts. Right now, the spines I'm using are at the bottom crossover point from another spine. With the tuning method you brought up, is there a rule or something which states that the sightpin should be as close to centershot as possible?

Oh, by the way, I aligned the string with the limb bolts during setup and it's the same during shooting.

[James Park]

Progen,
If it is tuned well, I definitely would not change things. If you were to change the points you would have to tune it all again.
If you are aligning the string with the limb bolts, the arrow point is then to the left of the string at full draw and you will need the sight even further to the left to get the arrows to go where you want. That is quite normal and is ok.

[Progen]

Ok, gotcha. Thanks James.

[TrevorK]

How much does the spine move by adding more point weight, is there a ratio to this?

trevor

[James Park]

How much does the spine move by adding more point weight, is there a ratio to this?
trevor
The spine does not actually change - it is the stiffness of the shaft, which is the same no matter what the point weight.
What happens is that the resonant frequency of the arrow decreases a bit if the point weight is increased. In that respect the resonant frequency moves in the direction of the resonant frequency of a shaft with less stiffness.
You need a shaft of lower resonant frequency if the bow is slower, as it takes a little longer to get from full draw to out of the bow.

However: you don't win much at all by changing the point weight. As you add point weight the resonant frequency goes down but because the arrow is then heavier it takes still longer to get out of the bow, needing the resonant frquency to go still lower, etc.
It is altogether better to simply change the bow's draw weight to tune it.

[Progen]

How much does the spine move by adding more point weight, is there a ratio to this?

trevor

I think what you meant was a change in spine rating.

From some costly experiments, it'd seem to range from 20 to 30 grains but that does depend on where in the recommended range you are. If you were at the extreme minimum, then a 30 grain one would send you to the next stiffer spine. HOWEVER, if you were right at the maximum recommended range and your arrows are showing some signs of almost being underspined, then 10 grains would ruin everything.

[TrevorK]

James, i got hold of some 620 carbon impact arrows which seem to be a weaker spine, so I'll try those to see what results I get compare to my 610 navs

Trevor

[TrevorK]

James, i've changed my limbs to winexs at 42# a 4 pound increase and my arrows tuned in ok, so all good now, thanks

[James Park]

Sounds good Trevor.

[KAJ]

Is it alright to tune a recurve bow a bit further a couple of days before a competition? would this change the sight settings at all?

[paulrb]

Is it alright to tune a recurve bow a bit further a couple of days before a competition? would this change the sight settings at all?


It depends on what you do... Change in anything that will alter anchor, nocking point, tiller, sight extension distance... etc etc... will have some effect. It may be minor and could be adjusted easily or thrown them totally out....

[James Park]

Is it alright to tune a recurve bow a bit further a couple of days before a competition? would this change the sight settings at all?
I is certainly likely to change the sight settings.

[TJ Mason]

Is it alright to tune a recurve bow a bit further a couple of days before a competition?
If I'm shooting against you, then it's fine by me! :D

[Progen]

I shoot a little in the kitchen on days when I can't or don't want to go to the open range. It's about 5 metres to the target bag.

Assuming that the bow has been tuned properly, how far does it take for an arrow to shake off that archer's paradox wigglies and get on line to the target?

[Archangel]

I shoot a little in the kitchen on days when I can't or don't want to go to the open range. It's about 5 metres to the target bag.

Assuming that the bow has been tuned properly, how far does it take for an arrow to shake off that archer's paradox wigglies and get on line to the target?
As long as a piece of string... ;-)

[Brocky]

As long as a piece of string... ;-)
:rofl:
What limbs are you using.
Not that I know much but, I thought arrows continued a paradox until they hit the target :rolleyes:

[Progen]

As long as a piece of string... ;-)

So once the arrow clears the riser, it should be on target immediately?

Brocky, Win & Win XQ-1s, mediums.

Reason I'm asking is because most of my shots end up a little on the left at 5 metres but at 18 and all the outdoor distances, they're fine.

With my previous setup, they ended up dead on target at 5 metres and fine at 18 and beyond until 70 and 90 metres at which they'd end up about 1 to 2 inches to the right.

[James Park]

Assuming that the bow has been tuned properly, how far does it take for an arrow to shake off that archer's paradox wigglies and get on line to the target?
The arrow will still be flexing (as per the Archer's Paradox) for many 10's of Metres after leaving the bow.

[Progen]

The arrow will still be flexing (as per the Archer's Paradox) for many 10's of Metres after leaving the bow.

What I meant initially was this.

From some of the slow motion videos of an arrow leaving a recurve bow, it did seem as if the arrow was out of line for a short distance as it left the riser and then it got back on target.

So my question was, 'What is that short distance?' Can it be said to be say 1 or 2 metres or does it vary greatly from setup to setup?

[Brocky]

So once the arrow clears the riser, it should be on target immediately?
Brocky, Win & Win XQ-1s, mediums.
Reason I'm asking is because most of my shots end up a little on the left at 5 metres but at 18 and all the outdoor distances, they're fine.
With my previous setup, they ended up dead on target at 5 metres and fine at 18 and beyond until 70 and 90 metres at which they'd end up about 1 to 2 inches to the right.
How often do you shoot 5 meters in a competition. I know which one I would prefer. Oh move the target 1-2 inches to the right at 5 meters :thumb: ;)

[James Park]

By and large, for a well tuned bow the arrow is mostly flexing, not rotating about its centre of mass. That flexing does continue for quite a while (and certainly for many 10's of Metres). At the bow, its amplitude will be around 15 mm.
If the arrow is rotating about its centre of mass, for a well truned bow it will be damped out more quickly - probably around 10M or so.

[Progen]

How often do you shoot 5 meters in a competition. I know which one I would prefer. Oh move the target 1-2 inches to the right at 5 meters :thumb: ;)

I tuned my bows with the method James highlighted in this thread so way I looked at it, if I had to shift my sight horizontally AFTER having the bare and fletched shafts dead on at 20 metres, then that'd be defeating the purpose of using this method, wouldn't it? ;)

And thanks, James. Got it.

[James Park]

Usually, if the bow is well tuned, any need to move the sight horizontally between distances is due to the sight bar not being vertical while at full draw, so I would check that. (Of course you need a very still day to do this because wind drift will mask it).

[Brocky]

I tuned my bows with the method James highlighted in this thread so way I looked at it, if I had to shift my sight horizontally AFTER having the bare and fletched shafts dead on at 20 metres, then that'd be defeating the purpose of using this method, wouldn't it? ;)

And thanks, James. Got it.
:rolleyes:
I'm with James

[KAJ]

- - Still with the solid pressure button, adjust your sight so that you are grouping around the centre of the target. If the arrows are going to the left, should you adjust the windage or will that effect the final tuning?

- Now that you have some give in the spring, you will need to push the arrow out a little from true centreshot, so adjust the pressure button position.


when adjusting the plunger button. Do we adjust the part where it says '1' or where it points to '2'? Hope you understand this.

[Sandy Hancock]

If the arrows are going to the left, should you adjust the windage or will that effect the final tuning?
That's exactly what you do *at the stiff plunger stage*.
when adjusting the plunger button. Do we adjust the part where it says '1' or where it points to '2'? Hope you understand this.
Depends on what you want to adjust.
If you want to adjust centreshot you want '1', if you want to adjust button tension you want '2'

[The One]

I think you want '1' for the position.

[alexvpaq]

just a lil question since I'm a great noob XD will these tuning going to be okay for my Indoor/Outdoor arrows or I'll need to retune it
( I doesn't bother me to retune it so that's not lazyness :silly: )

[Progen]

Simple answer. Are they made of the same materials and do they have the same spines? ;)

You can probably get away by playing around with the windage though.

[reversehaven]

hmm. i posted this in my other thread. Progen mentioned that there are times the easton charts aren't accurate. If so, then what can I do to make sure that my 450 X-10s will spine in for my new 44lb limbs? i haven't finalised the order yet, however I would like to know if they will spine in (or actually end up slightly stiff) i haven't really gone down to cutting them to size. i left them 1.5 inches longer than i should so i artificially extended my clicker temporarily till i get my limbs (then i can choose to cut bit by bit and try it till it spines in).

still, that being said, the question still remains. How can I be sure that my 450 x-10s will spine in for 30" and 44#? by the easton charts, they recommend 450 spine for 30" and 44 #.

[Sandy Hancock]

just a lil question since I'm a great noob XD will these tuning going to be okay for my Indoor/Outdoor arrows or I'll need to retune it
( I doesn't bother me to retune it so that's not lazyness :silly: )
The indoor arrow will be heavier, so (if I correctly understand a post from gt a while ago) for the same static spine it will behave weaker.
The indoor arrow will be fatter, so rest height, centreshot and nocking point height will have to change.

Upshot: you will have to retune. Some (like Frangilli I think) just shoot their outdoor arrows to avoid the hassles.

[Sandy Hancock]

still, that being said, the question still remains. How can I be sure that my 450 x-10s will spine in for 30" and 44#? by the easton charts, they recommend 450 spine for 30" and 44 #.
You're brave buying an expensive set of arrows before the limbs. What if their actual draw weight differs from your expectations?

That said, starting with the Easton chart and then adjusting draw weight using the limb tiller bolts works pretty well in most instances. You'll be right. It's only money ;)

[Foam hero]

Hello,

I would like to hear some opinions from skilled archers on this matter, though I know it depends much on personal technique, release particularly.

Which of these outcomings is best?

So, when tuning shaft with stiff plunger method with a paper or aforesaid method. There are 3 (good?) ways how it can end.

1. Shaft is a little on weak side(eg. tear on paper is about 1inch or less)

Arguments: Propably the most usual fault is collapsing bow arm and bad finger release, which makes shaft tune stiffer. -> When shaft is a bit on weak side, it doesnt act so far from the optimal on stiff side.


2. Perfect act according to tests.

Arguments: Shaft is flying very well on a good release, but when a failure happens arrow hits low because it is fishtailing more and drag is greater.

3. Shaft is a little on the stiff side(eg. tear on paper is about 1inch or less)

Argument: This is how I usually have seen it to be done.

Please explain me advantages and disadvantages of each tuning. Im only guessing with my arguments.

Oh and sorry, my bad English.

[reversehaven]

You're brave buying an expensive set of arrows before the limbs. What if their actual draw weight differs from your expectations?

That said, starting with the Easton chart and then adjusting draw weight using the limb tiller bolts works pretty well in most instances. You'll be right. It's only money ;)

hahaa.. yeah i realised how dumb that was. Actually I kind of bought it on moment of impulse to pacify my soon-going-insane mind. lol. i was like supposed to study for my exams at that time but all i could think of was the x-10s which i could just hop down to the dealer and get them. which i did.

well, whatever the case, i anticipated that the draw weight and i chose one spine higher. any problems, i'll just crank up.. or lighten the string... or leave my arrows slightly longer. they're still about 1.5 inches longer than the correct arrow length (as shown in the easton arrow guide.) i guess... i hope... it shouldn't be a problem.

thanks for the reassurance :)

[burt666]

- Select the correct string length. This should ensure that the correct amount of string is sitting around the recurve on each limb. It is best to use the manufacturer's recommended brace height.


James, in theory, would yo be ablt to adjust you horizontal bare shafts grouping by adjusting the brace height?!? or would you recommend draw weight only?

[James Park]

Yes, you can adjust the bare shaft tuning using brace height. but I think it is better to use the draw weight. I prefer to have the string length such that the string sits optimally on the recurves.

[Max S.]

G'day James,

on my recurve hunting bow I have quite heavy fletch contact with the rest and riser. Does this mean my arrow has too stiff a spine or to soft?

Thanks in advance.

Max

[James Park]

Max,
Could be either of those.

[Max S.]

Thanks James, I'll retune and see which it is.

[Progen]

Had a little idea when redoing the center serving last night. Since slowing or speeding up the string will affect how the arrow behaves, wouldn't that mean that increasing or decreasing the length of the center serving will have a little effect too? Not much though. Perhaps closer to how much effect playing with brace height would have.

[alexvpaq]

After some work and tuing with this technique, everything seems to works fine but the vane is touching the bottom of the bow shelf... what can I do to resolve this problem?:confused:

[burt666]

After some work and tuing with this technique, everything seems to works fine but the vane is touching the bottom of the bow shelf... what can I do to resolve this problem?:confused:

maybe shaft selection problem.

[alexvpaq]

maybe shaft selection problem.
maybe anyway I got to work on my tuning (cause I got a riculously low level of experience at tuning bows):silly:

[James Park]

Had a little idea when redoing the center serving last night. Since slowing or speeding up the string will affect how the arrow behaves, wouldn't that mean that increasing or decreasing the length of the center serving will have a little effect too? Not much though. Perhaps closer to how much effect playing with brace height would have.
The mass of the serving has a strong effect on bow tune. This is because the bow's virtual mass is a key contributor to the efficiency of the energy transfer. Changing the length of the serving impacts the virtual mass quite strongly because it is the part of the string that moves the most.
This is also the reason why bow manufacturers put very little centre serving on their compound bows: since arrow velocity seems to be a rather strong selling point (as distinct from accuracy).

[Archangel]

After some work and tuing with this technique, everything seems to works fine but the vane is touching the bottom of the bow shelf... what can I do to resolve this problem?:confused:
Nocking spot being too high seems like a likely kind of explanation for that.

[alexvpaq]

Nocking spot being too high seems like a likely kind of explanation for that.
thanks I'll try to move it a bit higher ;) quite funny that you're always going in the side of the problem in archery to make things better...

Ok everything tuned fine ;) finalized everything with a paper tuning and it was a good one =D!
(and no more problem with the vane)

[c0rbuu]

Hi James, what is your experience with tuning lower poundage bows? I am trying to tune my bow with your technique but I can't get an arrow with a week enough spine. My bow is a 68" recurve with #26 on the fingers (evolution II limbs). Arrow length is 28.5" and the string is a 10 strand fast flight. I am using Redline 900s which according to chart are already way underspined but they are still showing stiff, i.e. bareshafts hitting 2" left at 20m and I seem to get a bit of fishtailing. I must be doing something really wrong here... :confused:

[reversehaven]

The mass of the serving has a strong effect on bow tune. This is because the bow's virtual mass is a key contributor to the efficiency of the energy transfer. Changing the length of the serving impacts the virtual mass quite strongly because it is the part of the string that moves the most.
This is also the reason why bow manufacturers put very little centre serving on their compound bows: since arrow velocity seems to be a rather strong selling point (as distinct from accuracy).

i have been thinking about this and was about to ask till i chanced on you saying this on the forum.

though if you put too little serving material on the string you end up with a case where your string is under protected (by say, hits on the arm guard) how do you know (for a recurve) how much serving do you put on the string?

[James Park]

In their quest for higher velocity specifications, I think the manufacturers put too little centre serving on the string.
Reducing the centre serving amount is a very obvious way to get higher test velocities. Reducing the number of strands in the string is also very effective. Both of those reduce the bow's Virtual Mass, which directly leads to greater energy transfer.
For example, on a flight-shooting bow (where you are solely after distance), you would normally use 6 strands and next to no centre serving, and expect to break a string every shot.
However, both a poor things to do for a normal bow.
I would normally remove the manufacturers serving when it is too short, and then serve it sufficiently above the nocking point so that my bow square sits on serving, not string, and sufficiently below the nocking point so that the serving touches my arm and not the string strands. Sure that costs me a few ft/sec, but it is better practice.

[reversehaven]

cheers. that's a good gauge. :) thanks.

[scrounger2]

Hi everyone,
I have no tuning experience: my bow had been tuned by a pro (who is considered a real guru around here) and is shooting very well. Nevertheless, I'm curious: does anyone shoot with INVERTED tiller? I measured mine to be the lower limb at 7 1/2" (190mm) and upper at 6 7/8" (175mm) that means 5/8" tiller the other way...
I shoot 25" GM with evo 2 long limbs, brace at 8 3/4", ~30lbs at 29 1/2".
Rob

[burt666]

Hi everyone,
I have no tuning experience: my bow had been tuned by a pro (who is considered a real guru around here) and is shooting very well. Nevertheless, I'm curious: does anyone shoot with INVERTED tiller? I measured mine to be the lower limb at 7 1/2" (190mm) and upper at 6 7/8" (175mm) that means 5/8" tiller the other way...
I shoot 25" GM with evo 2 long limbs, brace at 8 3/4", ~30lbs at 29 1/2".
Rob

Michele Franguelli does!

[The One]

A few people prefer the feel of the reaction that way, but most have a positive or neutral tiller.

[James Park]

The limbs are usually designed to have positive tiller. I would usually prefer to use my bow the way it was intended by the designer.

[scrounger2]

Michele Franguelli does!

Thanks, I was affraid to hear some "big-no-no-no-way" responces.
So I guess, step no.2: "- Set the tiller. Make the top tiller about 1/8" greater than the bottom tiller." is is not completely set in stone. Or is simply meant as a starting point?

BTW, great thread with a ton of info. Will take me a while to sort it out... :D
Rob

[Archangel]

Yes, it's just a starting point. Obviously you need to set it up to suit you - there's no magic number that works for everyone.

Having said that, 5/8" of negative tiller is very strange - I find it hard to believe that's actually where your bow seriously tunes out best.

[Brocky]

Hi everyone,
I have no tuning experience: my bow had been tuned by a pro (who is considered a real guru around here) and is shooting very well. Nevertheless, I'm curious: does anyone shoot with INVERTED tiller? I measured mine to be the lower limb at 7 1/2" (190mm) and upper at 6 7/8" (175mm) that means 5/8" tiller the other way...
I shoot 25" GM with evo 2 long limbs, brace at 8 3/4", ~30lbs at 29 1/2".
Rob
Tuned by a pro for the pro :rolleyes:

[scrounger2]

Yes, it's just a starting point. Obviously you need to set it up to suit you - there's no magic number that works for everyone.

Having said that, 5/8" of negative tiller is very strange - I find it hard to believe that's actually where your bow seriously tunes out best.

You might be absolutely right and Hoyt manual says it should be 0-3/8" but these are cheep evo 2 limbs after all... I didn't have occasion to shoot past 50m yet (damn winter) and on bad day even 25m is all over the place. However, I'm starting to be decent at 18m so it cannot be all bad. My tuning so far had been limited to getting proper arrows and the button working right.

Frankly, I'm affraid to tinker with the bow as it feels really nice: my shooting with recurve is still far from what I would consider consistant so I'd probably wouldn't be able to tell if it gets worse... :(
Rob

[burt666]

Frankly, I'm affraid to tinker with the bow as it feels really nice: my shooting with recurve is still far from what I would consider consistant so I'd probably wouldn't be able to tell if it gets worse... :(
Rob

That's the deal: there is a big difference in between feeling something nice, and getting use to that feeling.... and i'd think that what happening right now, you're just getting used to your bow set that way, so it feels comfier and comfier...

And if it's still winter ovethere, well, give the tuning a ago while you're indoor, my guess is you won't loose much time to get it back to where it was if it really doesn't suite you....

[scrounger2]

That's the deal: there is a big difference in between feeling something nice, and getting use to that feeling.... and i'd think that what happening right now, you're just getting used to your bow set that way, so it feels comfier and comfier...

And if it's still winter ovethere, well, give the tuning a ago while you're indoor, my guess is you won't loose much time to get it back to where it was if it really doesn't suite you....

All right, I think I needed the confidence boost. I hope the packet adjustments are not too fancy. Will let you know how it goes.
Thanks again,
Rob

[Vittorio]

Michele Frangilli does!

Not at all. He only shoots zero tiller (explantion in THA)!

Last top archer to shoot with negative tiller was Andrea Parenti, 3 times Filed World Champion, some years ago.

[gt]

Not at all. He only shoots zero tiller (explantion in THA)!

Last top archer to shoot with negative tiller was Andrea Parenti, 3 times Filed World Champion, some years ago.


Vittorio,

You seem to have forgotten Paul Vermeiren, 4th at the Atlanta Olympics, and well after Andrea's last international event.

[burt666]

That was easy....

just switch from my 34# long G3's to shoot User-Name 's 36# medium F\X limbs, and adjusted the tiller to the figure i had before. As my string in D75 was too long, i got one of The One old angel majesty's string, as he shoot medium limbs too, and tuned the nocking point / brace height to reasonnable values

got indoor today to look what the bare shaft tuning would give...

And, well, i'm just spot on whitout touching anything....:silly: :silly: :silly:

[The One]

That was easy....

just switch from my 34# long G3's to shoot User-Name 's 36# medium F\X limbs, and adjusted the tiller to the figure i had before. As my string in D75 was too long, i got one of The One old angel majesty's string, as he shoot medium limbs too, and tuned the nocking point / brace height to reasonnable values

got indoor today to look what the bare shaft tuning would give...

And, well, i'm just spot one whitout touching anything....:silly: :silly: :silly:

I'll take a 10% commission of all your winnings ;)

[ehair]

James, what do you think then?, #38 limbs, draw lenght 28" and an arrow lenght of 28" and easton say navs 610 are the way to go. Onlyy been shooting a couple of years and can shoot 545 portmouth.

Trevor

Dear Trevor, easton's chart really cost me alot of money, i am 28" draw, 40-45 pounds weight, easton reccomends 550 x-10's, SURE! the arrows only grouped at 37 pounds bare shaft at 20m...

[The One]

Dear Trevor, easton's chart really cost me alot of money, i am 28" draw, 40-45 pounds weight, easton reccomends 550 x-10's, SURE! the arrows only grouped at 37 pounds bare shaft at 20m...

The required spine will change based on the exact length of the arrow (how far in front or behind the back of the riser you draw it), point weight, brace height, number of strands in your string, weight of serving, and TECHNIQUE!

Thus, the charts are more expectations, but not definates. Try changing some of the other variables to get them to tune. (remember, the tuning process will only give you the correct results for bareshafts if you have the centreshot etc. correct)

[Sandy Hancock]

Dear Trevor, easton's chart really cost me alot of money, i am 28" draw, 40-45 pounds weight, easton reccomends 550 x-10's, SURE! the arrows only grouped at 37 pounds bare shaft at 20m...
The Easton charts are generally very reliable. If your tune is that far out, search within to find the problem.

[Progen]

I'm having some funny results with my A/C/Es too. Perhaps it's time to look at the McKinney II or Nano XRs to go with my Winex / Aerotec combination.

We can rob energy from the string easily but where the hell did all the extra come from. Now that's the strange part. :rolleyes:

[burt666]

I tried the search function, but couldn'e come with anyhtnig, so here u go...

Any suggestion to fine tune the tiller?!?

1 - set it at 1/8" forget about the dam thing, life's too short for bad tiller.
2 - tune it so your bare shafts arrive in the butt at the same sort of angle as your fletched arrows? (read it on some french site, but never heard about it before)
3 - try to determine if your sight haS the tendency to go up-down when your are coming to full draw (i don't remember the way that particular tuning is supposed to go actually, if someone knows the answer...). You would like it to be as steady as possible, and adjust the tiller according to this?!?

[The One]

(i don't remember the way that particular one is supposed to go actually, if someone knows the answer...)

Preferably neither way - you want it to hold steady as you draw through the clicker.

[burt666]

Preferably neither way - you want it to hold steady as you draw through the clicker.

thks ;) but still if you notice a tencency in the few sec your are at full draw, how could you adjust the tiller accordingly?!?

(i edit my last post to make it clearer)

[Archangel]

thks ;) but still if you notice a tencency in the few sec your are at full draw, how could you adjust the tiller accordingly?!?

(i edit my last post to make it clearer)
If the sight wants to pull up as you're coming through the clicker, that means your top limb is too stiff, so you want to back that limb bolt off a bit.
Conversely, if it's pulling down, lighten the bottom limb. They should be really really fine adjustments by that point.

[Progen]

The sight moving up at you approach anchor seems to encourage the archer to draw slightly lower before raising the arm to anchor at the chin. More usage of the lower back. ;)

Although I don't think that's the main reason for a positive tiller.

[burt666]

The sight moving up at you approach anchor seems to encourage the archer to draw slightly lower before raising the arm to anchor at the chin.

yeah, but if u don't draw like that?;)

[Progen]

yeah, but if u don't draw like that?;)

In that case, you have nothing to worry about since you were screwed from the start. :D

[burt666]

In that case, you have nothing to worry about since you were screwed from the start. :D

schuch, or i positive rep you!:p

[alexvpaq]

schuch, or i positive rep you!:p
I'll give you more rep so it'll be more effective :rofl:

[Archangel]

Although I don't think that's the main reason for a positive tiller.
No, my understanding was that the main reason is because your grip isn't level with the arrow, so it doesn't want to be a perfectly neutral setup.

[burt666]

No, my understanding was that the main reason is because your grip isn't level with the arrow, so it doesn't want to be a perfectly neutral setup.

that's my understanding too...

1595

[Brocky]

If the sight wants to pull up as you're coming through the clicker, that means your top limb is too stiff, so you want to back that limb bolt off a bit.
Conversely, if it's pulling down, lighten the bottom limb. They should be really really fine adjustments by that point.
I agree with archangle, however another way to go about this is to get someone else to observe your stabiliser whilst you draw the bow back. In doing this make sure you draw the bow back straight to your anchor point, dont lift or drop your draw arm.

[Progen]

I think we've forgotten that the majority of stabilizer choices are that. Choices, not a determination arrived by calculations. And I dare venture that the majority of those using stabilizer setups which are theoretically correct use them because they're convinced that it will help their shooting, not because they like the dampening, stabilizing or aftershot characteristics.

[spangler]

Firstly, thanks for posting this. I have a question that I can't seem to solve however.

bow setup:
25" Nexus riser
40# Samick universal SHORT limbs
Easton A/C/C 3-00, FF187 fletch, G-nocks, 100gr breakoff points
14 strand string
Jaeger BEST grip
BH 9.75"

archer setup:
DL 24"
arrow length from nock groove to end of shaft 23 5/8"
34.5# on the fingers


If your arrows are the correct size, the following process is easy, fast, accurate and repeatable.


sounds good so far


Steps:
- Select the correct string length. This should ensure that the correct amount of string is sitting around the recurve on each limb. It is best to use the manufacturer's recommended brace height.


Check


- Set the tiller. Make the top tiller about 1/8" greater than the bottom tiller.


Check


- Align the limbs. You need to end up with the string running centrally down the limbs and the riser, and for the riser not to be twisted off to one side.


Check


- Set the pressure button so that there is zero movement (I put a match in it). Then adjust the centreshot so that the arrow is sitting exactly on centre.
- Shoot some fletched and some unfletched arrows at about 15-20M. Adjust the nocking point so that the fletched and unfletched arrows hit at the same height.


Check


- Adjust the bow's draw weight so that the fletched and unfletched arrows hit the same place horizontally. Note that if the arrows are not the correct size, this step will not be possible, and there will be little you can do to fix it (sell the arrows and buy new ones - with a recurve bow you really do need to get the exact correct size, one size wrong will not tune correctly even with much frustrating tinkering). If the bow draw weight will not go high enough you can try a lighter string. If the bow draw weight will not go low enough you can try a heavier string.


Check, although they might be slightly weak, bare shafts group 1/2" to the right of the group.


- Still with the solid pressure button, adjust your sight so that you are grouping around the centre of the target.


And it is all over.

While the bare and fletched shafts group (1.5" group at 18M, I am unable to get the group into the center of the target. They are all in the 1 ring on the left side of a 40cm target. The sight is out of travel. The sight picture has the string on the left side of the riser at full draw.

I have double checked and the shaft is sitting dead on center of the riser. I've watched the bow hand very carefully and the riser isn't being torqued or twisted at all. The shot looks very good, and the arrow flies very nicely, just way over to the left.

To avoid eye dominance issues, the archer is wearing an eyepatch over her left eye.

What is this telling me?

-Andrew

[The One]

For grouping problems like this, it is often to do with the head position and string alignment. Check that her head is upright, and that at full draw, she can line up the 'out-of-focus' string with the inside of the sight window of the riser, or alternatively, just next to the sight. If the shots are then not grouping near the centre, then I'd start to look at aperture length etc.

A good way to get an intial idea as to whether it is the bow or the archer, stand directly behind them at full draw, imagine a line fromt he string through the centre of the riser (often you can only see the top of the riser from the back - use the top limb locking bolt), and carry this through tot he target. If this line is roughyl central, then it's something to do with the equipment (or something is going wrong big time int he release), and if the bow is pointing that way, then either the sight isn't int he right place, or the archer's sight picture is incorrect :)

[burt666]

What is this telling me?

-Andrew

Using quickly Easton online spine selector, it can up that your edquate spine for ACC's should be 2-00, but i've made a very quick check... try to do it too, and check what they define as "arrow lenght", "draw lenght", etc... i can't remember what's teh difference from the top of my head...

My guess is if your really one spine too stiff, your arrows will land on the left regardless you what you do....

Also assuming your riser is a 25" one, with short limbs you then get a 66", and 9 3/4" of BH sounds way to much for such a set up.... try to reduce it by 1 1/4" if you can (or get a lonfer string made) and check if it change something...

Good Luck with your tuning!:thumb:

[spangler]

For grouping problems like this, it is often to do with the head position and string alignment. Check that her head is upright, and that at full draw, she can line up the 'out-of-focus' string with the inside of the sight window of the riser, or alternatively, just next to the sight. If the shots are then not grouping near the centre, then I'd start to look at aperture length etc.


That is what we have been doing, working on her string picture, and she reports it is on the inside of the sight window. I'll have to double-check some pictures, but I believe her head is upright.

Ap length is 9 inches, but we have left issues even when it is pulled in.


A good way to get an intial idea as to whether it is the bow or the archer, stand directly behind them at full draw, imagine a line fromt he string through the centre of the riser (often you can only see the top of the riser from the back - use the top limb locking bolt), and carry this through tot he target. If this line is roughyl central, then it's something to do with the equipment (or something is going wrong big time int he release), and if the bow is pointing that way, then either the sight isn't int he right place, or the archer's sight picture is incorrect :)

Well, I can stand behind her and things seem to be lined up correctly. Then I can watch the arrow take off straight (and flying great) to the left. I'll have to consult the many pictures I have taken again. If it is equipment, what do you think it would be at this point?

Thanks for the thoughts...

-Andrew

[The One]

When you say the sight is 'out of travel' what do you mean? If it's that the windage screw has reached the end of its travel, the actual aperture can be screwed in or out as well.

With the bow at rest, line the string up with the limb bolts, and see whether or not the sight is to the left or the right. If the sight is to the right, this may be the problem, and you should unbolt and twist the aperture thread out a bit until it is closer to the centre.

[spangler]

When you say the sight is 'out of travel' what do you mean? If it's that the windage screw has reached the end of its travel, the actual aperture can be screwed in or out as well.

With the bow at rest, line the string up with the limb bolts, and see whether or not the sight is to the left or the right. If the sight is to the right, this may be the problem, and you should unbolt and twist the aperture thread out a bit until it is closer to the centre.

Sadly, I meant that the aperture itself is screwed out until it is out of travel. When looking at the bow with the string lined up with the limb bolts, the sight aperture is well to the left of the string.

[spangler]

Using quickly Easton online spine selector, it can up that your edquate spine for ACC's should be 2-00, but i've made a very quick check... try to do it too, and check what they define as "arrow lenght", "draw lenght", etc... i can't remember what's teh difference from the top of my head...

Using the Easton target chart (for youth) she is in Y5 on the border of Y6. Y5 suggests the 3L-04 and Y6 the 3-00. This is why we got the 3-00 and put 100gr points in the front.


My guess is if your really one spine too stiff, your arrows will land on the left regardless you what you do....


Right, but since the bare shaft and fletched shafts group together with the stiff plunger (as noted in the tuning method on this thread) shouldn't this indicate that the spine is correct?


Also assuming your riser is a 25" one, with short limbs you then get a 66", and 9 3/4" of BH sounds way to much for such a set up.... try to reduce it by 1 1/4" if you can (or get a lonfer string made) and check if it change something...

Good Luck with your tuning!:thumb:

Good point, the Hoyt manual suggests 8 1/4 to 9. Perhaps that is part of the problem.

[Sandy Hancock]

Just to get this clear. You still have the plunger stiff and perfectly centre-shot? If the answer is yes I would look at head position, face contact and string alignment as others have mentioned.

[Angela]

Just to get this clear. You still have the plunger stiff and perfectly centre-shot? If the answer is yes I would look at head position, face contact and string alignment as others have mentioned.

I am the archer in question. Yes, the plunger is stiff and perfectly center-shot when these problems occur.

Here is a picture from the back showing head position. For string alignment, it is aligned with the middle of the riser. This is very frustrating.

[Sandy Hancock]

It's hard to be sure from the photos, but I suspect your head should be rotated a little more to face the target. That would lighten the contact of the string with your chin, and possibly line your eye up better.

Mr Lee used to recommend aligning the string with the right edge of the sight ring. It might also be worth a try.

[whiz]

Is it just my observation that the young ladies Vbar setup is a lot higher on the right than the left? It's not just the angle. Look at the ends of the bars..

Still doesn't solve the problem. Just something curious.

[The One]

Hi Angela,
Yeah, from those photos, it seems the alignment isn't the cause. Do you have some Beiter limb gauges? Often the limbs can both be off to one side, though the string will still appear vertical.

The most useful thing would be a short video or two if you have the capability of taking one and getting it on the net.

[Artemis]

One of Jim's assumptions before starting the tuning process is that all clearance issues have been resolved.

I would be checking for arrow clearance - my experience is that arrows that are too stiff may still appear to "tune" and group well although the reality is that the rear of the arrow and/or nock may be contacting the arrow rest and/or pressure button. A powder test will resolve this quite quickly.

The other clearance issue could well be the chestguard. Check for contact and wear along the binding.

[Marcus]

What poundage are you holding at full draw? While they are 40lb limbs my guess is you must only be holding about 32-34#

In which case the 3-00 is likely correct.

I would have a look at your string alignment and limb alignment. Artimis also makes good suggestion in the string clearance.

[burt666]

34.5# on the fingers
good thinking!:)

[spangler]

Thank you to everyone who has posted. In response to the questions asked:

Marcus - good guess 34.5# on the fingers.
Artemis - I figured it could be that also, so I have performed the powder test several times and didn't appear to be getting contact with the rear portion of the arrow at all. I'll try this again tonight however.

The chestguard isn't getting contact.
Yes I do have Beiter limb gauges and two days ago we checked string and limb alignment and it is in good shape.

Her head is indeed swiveled a bit away from the target, with her face straight on she wasn't able to get a string picture, it was 2 inches to the right of the riser. She tilted her face a bit putting the string on the left side of her nose and this gave her the sight picture we were looking for. One thing not shown in these pictures is that she has a very open stance, we have since closed that up just a bit and that has helped her get a better sight picture.

Yes, the V-bars were all screwy in that picture. That photo was taken in the middle of a tournament in which I twiddled the v-bars into that config to see any effect it might have on moving the group to the right. I was worried there might be some last second canting of the bow I wasn't seeing. I know correcting canting via v-bar position change is not the right thing to do (just fix the grip)...but we were in the middle of the tournament and I had to do something.

So, here is what I am down to:

Double check via powder test that with a stiff plunger and centershot I have no contact on the back half of the arrow.

Straighten up the face with the target (point the nose more toward the target) and ensure string picture is on the left edge of the sight window of the riser (every time).

What is odd to me is that she can group 4-5 inches at 70M all day long, but the group is over in the 1 or 2.

As an aside, I have ensured that the sight bar is level and not canted left or right as the sight is moved up and down.

I will attempt to get a video of her shot and post it online for suggestions. I'm sure she will love that :)

-Andrew

[franklin]

spangler
try thin finger tabs, that might hurt.
still you get some info from the action.

[Jay.G]

Well finally used this method to tune my arrows today. Everything seemed to work except now my arrows are pointing quite to the left and far from what I used to have set up as the centre-shot. However it is lined up with my aperture ring/dote. Also now when I shoot the bareshaft is about 3 scoring zones to the right.

http://i215.photobucket.com/albums/cc136/Jaygong/20081003-01.jpg - plunger position
http://i215.photobucket.com/albums/cc136/Jaygong/20081003-02.jpg - arrow position

Seems pretty diagonal to me... So question is, is that okay or did I seriously do something wrong? It just doesn't look normal to me... Would there be some other problem with this set-up?

From 18m the flight seemed pretty good but it did seem rather erratic at first though I think my plunger might've come loose but now it seems pretty good and groups nicely.

[Progen]

Seems to indicate a weak spine in your case, Jay.G.. It might be alright for short distances but I suspect you'll have to adjust your windage settings for further distances because you are only tuning at short distances now.

If the spine's right, tuning's a breeze and on non windy days, the windage setting is the same from your indoor 18 right up to the outdoor 90 metre target.

[Jay.G]

but is the arrow pointing that much to the left be an actual acceptable/plausible conclusion to using this tuning method? Or should I just go back and tune with the Easton method?

[Progen]

This method is very useful in showing how well matched your chosen spine is to your poundage / shooting style. There is no need to go for walkback testing if you can get them to group at 20ish metres. Mine still grouped at 30 and I was really surprised. Sightring was a little outside the riser's centerline.

Your point needs to be pointed out to the left so much to correct for the fact that when brought to a tad outside centerline, the arrows will end up to the right when shooting for tune. That indicates a weak spine for a right handed archer. Perhaps you can try slightly heavier fletches and arrow wraps to bring them closer to tune with your setup. What you're doing now is basically to compensate with the plunger to get them in the gold at 18 metres. At further distances, the 18 metre compensation will be insufficient and you will find your arrows landing to the right again. The further you go, the further right they'll go. Who knows? You might not even be able to hit the target at 90 metres. :D

[Archangel]

but is the arrow pointing that much to the left be an actual acceptable/plausible conclusion to using this tuning method? Or should I just go back and tune with the Easton method?
Well, personally I wouldn't be keen on that result, regardless of how you got there - but that's just me, Jim or others may have a different opinion on it.

[Jay.G]

Yea that was my first impression but the first time I tuned just using the normal set up of setting up centre shot so arrow's point' right side just touches the left side of string with the plunger tension of 'something nice', the bareshaft grouped fine with the rest of the arrows at 18m. So maybe today I'll just re-tune with Easton instruction?
However I think I may shoot from 70m or so to see how they go first.

Any advice jim?

[Progen]

Way I look at it, playing around with plunger tension to get in the center at different distances is just like having different plunger tip positions.

[Sir Slick]

Well finally used this method to tune my arrows today. Everything seemed to work except now my arrows are pointing quite to the left and far from what I used to have set up as the centre-shot. However it is lined up with my aperture ring/dote. Also now when I shoot the bareshaft is about 3 scoring zones to the right.

I used this tuning method with mine and from memory you have a similar setup to me. When I did the tuning at 20m my bareshafts were going right in the centre of my group. Target back to 70metres same thing.

I agree with what others say, your arrows sound like they are too weak.

What size points did you go for in the end??

Edit: Also tips of my arrows were nowhere near that far left

[Jay.G]

100grain points, though now my arrows made up to 31' exact, so that might've be the problem since my draw length is 29'. I really don't want to cut the arrows as I might grow again so at this moment I think I'll decide to just re-tune it normally (Easton, plunger tension etc.) as best as I can.

[Sir Slick]

That extra length would explain why they're spining soft....no need to cut off just do what you were originally going to, try lighter points.

[Jay.G]

Well I've completely re-tuned them today and they're working rather well now and yes still a tad on the soft-side but I rather get on with my proper training with minimum interruptions.

[Sandy Hancock]

If you have used the method in this thread correctly, your arrows can not be too weak; that is the whole point of the centre-shot/stiff plunger bit at the start.

If you can adjust the bow weight to cause fletched and unfletched arrows to group together (with the plunger stiff and set to centre shot) you have appropriately spined arrows by definition.

If you've done all the preliminary stuff properly I'd be very surprised to see arrow alignment needing to be that far left. Perhaps brace height may not be optimal, but I doubt that would be enough to account for this.

[burt666]

I've tried this tuning method the other day... and whatever i was doing if the poundage adjustment, with stiff plunger, my bare shaft appeared always a wee tiny on the weak side (2-3 inches, at 18m indoors)

does that mean my shaft were too weak anyway? or is that an acceptable margin??? Jay told me he was having the same sort of issues too...

[Progen]

If you have used the method in this thread correctly, your arrows can not be too weak; that is the whole point of the centre-shot/stiff plunger bit at the start.

...

There's your reply already given almost 4 weeks ago. Sandy must be psychic! :o

[Sandy Hancock]

I've tried this tuning method the other day... and whatever i was doing if the poundage adjustment, with stiff plunger, my bare shaft appeared always a wee tiny on the weak side (2-3 inches, at 18m indoors)

does that mean my shaft were too weak anyway? or is that an acceptable margin??? Jay told me he was having the same sort of issues too...
What are the details of your set-up burt666?

[burt666]

Hoyt AeroTec 25" (black!;) ) + KG Apex limbs 68" 36#

ACE 620, 100gr points, pin + easton nocks, Bohning 1.75" Xvanes, 29.5" from bottom of groove to END of point

String Angel Majesty 18 strands

Magnetic rest Spigarelli, Arc System "Competition" button, etc....

[Jay.G]

lol when did you change to the APEX? thought you were using the QILs?

[Brocky]

Try a different string material.

[Acehero]

Heres my setup:

Hoyt Matrix riser
Seb flute 36lb limbs, last measured was 40lb's on my fingers
452x string with 2 floss nock points
xx75 1916 arrows measuring 28 7/8"
I'm right handed.

When i last has these tuned and shooting well I'd used the walkback method and just increased the tension on the button until they formed a nice line down the target. Ended up with a very stiff button but i expected that as according to the easton charts they are right on the upper limit of their group at this length and poundage. Shot well for about a month at all ranges outdoors. Anyway recently been having trouble and decided to get back to basics and make sure my tune was correct.

Using the method in this thread I was expecting them to show up weak. Setup the button with a matchstick, set centre-shot right down the middle of the string and riser etc as instructed and put a boss up at 20yds. The arrows grouped well over to the left (black/white) with the bareshaft almost off the target altogether (further left). Wasnt expecting the bareshaft to show up stiff! I wound the limbs down a bit to check and sure enough the bareshaft missed the left side of the boss. I had to wind the limbs up to the very max they would go to get the bareshaft grouping with the fletched arrows and even then it still favoured the left side of the group. Also, to get the whole group hitting the gold I had to move the sight ring out an extreme amount (still got the solid button set at this point) and the whole thing just didnt feel right.

I cant believe my arrows really are too stiff, especially when i had them tuned before quite well so I'm more inclined to think ive done something wrong with this tuning method, or something else im doing is skewing the test. Anyone got any suggestions? I did get hold of a barefletched xx75 1816 that was lying around the clubhouse and that went well right of the fletched 1916's at max poundage - though not so noticeably at other settings and unfortunately the owner of the rest of that set wasnt around so I couldnt try tuning with the rest of the 1816's.

[James Park]

The other thing you need to check is that you have a clear path for the string after the release. That is: that you are not anchoring with the string on the side of your face.

[Acehero]

Thanks for the quick reply. The string contacts me in the centre-front of my chin so I think its path is clear. I had a search and found a couple of old threads on another forum with a similar problem. Possible causes suggested there were the loose or torqueing the bow. I'll see if I can get somebody to watch my form next time and try tuning again.

[James Park]

Yes, twisting the bow would do it.

[Bottom Dweller]

When i last has these tuned and shooting well I'd used the walkback method and just increased the tension on the button until they formed a nice line down the target.

Me too. I tried the setup method here and no matter what I tried I couldn't get the fletched and unfletched arrows to group. The unfletched arrow always went to the left (I'm RH). Perhaps I did something wrong, but I'm pretty sure I followed the instruction to the letter. 36lb Samick Masters, 900 Cartel Triples, fastflight string, pulling about 34lb at full draw.

So I went back to the walkback test and sure enough they grouped.

James, why stiffen the button before this method? Doesn't that just exagerate the left movement of the arrow?

It seems to me that the only way this method would work is when you have very stiff arrows that don't bend against the button.

[Marcus]

What length arrow are you using? 900's sound way to weak to me. Unless you have a 25" draw length.

[Bottom Dweller]

26.5"

They are probably a little weak but still within the range suggested by Cartel.

[KAJ]

i have the same problem, 27 3/4" draw, 28 3/4" arrow length, 30#, (recurve) and at 20m the bare shaft would miss the target and head straight off to the left (im RH) where my group is in the middle (quite a tight group as well)
19-14 x7's btw

[James Park]

The method really does work.
Things that can cause you not to get the fletched and unfletched arrows together are:
- The arrow size is not tunable.
- String contact on your face.
- Twisting the bow.

Other than those, if the arrows are tunable within the weight adjustment range of the bow it should be just fine. If the arrow size is not correct it will not be possible to get it to work well.

The method uses the rigid pressure button so that you can be sure that the arrow is exiting on true centre.

[Bottom Dweller]

The method uses the rigid pressure button so that you can be sure that the arrow is exiting on true centre.


Jim,

I've been think about this (which is very dangerous!)

Is the theory that a full draw the front node point, around which the arrow bends, is supposed to be where the pressure button is, so that the first bend of the arrow toward the riser can occur without any significant pressure from the arrow on the button?

If so, it is possible that I have too much weight in the nib and hence the front node is forward of the pressure button hence explains the excessive left motion of the arrows?

I understand that a weak spine will also cause excessive pressure on the button and cause left movement of the arrow. However I would have thought that I need to get the front node in the correct position first before looking to get a stiffer arrow.

In this case the solution may be as simple as reducing the weight of the nib and hence shifting the front node point back a little.


Does this make sense? Is there any easy way to determine the correct nib weight and hence the correct front node point?

[Brocky]

The method works

[Progen]

The method works

:thumb:

Hate to agree with my buddy up there but I'm an advocate of this method. Fast, reliable and the same results can be arrived time and time again (with the same setup and archer).

[Marcus]

Your best solution is to buy suitable arrows.
Your best bet is to look at the Easton charts and then do a search on here for Triple Spines and then pick the closest spine. The 900's are about a 950 spine Easton. The Easton charts suggest a 1816, or a 850 spine, so you are a size too weak. A 800 Triple should come in nicely.
By trying to mess with other things like point weight and plunger tension you are simply introducing errors to fix errors. You won't get the best results that way.

Jim,

I've been think about this (which is very dangerous!)

Is the theory that a full draw the front node point, around which the arrow bends, is supposed to be where the pressure button is, so that the first bend of the arrow toward the riser can occur without any significant pressure from the arrow on the button?

If so, it is possible that I have too much weight in the nib and hence the front node is forward of the pressure button hence explains the excessive left motion of the arrows?

I understand that a weak spine will also cause excessive pressure on the button and cause left movement of the arrow. However I would have thought that I need to get the front node in the correct position first before looking to get a stiffer arrow.

In this case the solution may be as simple as reducing the weight of the nib and hence shifting the front node point back a little.


Does this make sense? Is there any easy way to determine the correct nib weight and hence the correct front node point?

[James Park]

I think Marcus is correct - you probably have an incorrect arrow size.
Yes, it does matter where that front node is, however changing the point weight does not move it much at all.
Changing the point insert length can affect how the arrow flexes quite a lot. so that is important.

[Progen]

...
By trying to mess with other things like point weight and plunger tension you are simply introducing errors to fix errors. You won't get the best results that way.

Word! If it's right, it's right. It'd be a matter of getting the bare and fletched shafts together within inches (and quite often centimetres too). Not as in one misses the target altogether and the other stays on. I've done this test almost up to 30 metres (wasn't exactly 30 but close) and they still grouped together.

[Bottom Dweller]

Changing the point insert length can affect how the arrow flexes quite a lot. so that is important.


That's interesting. I have the original Cartel 900 nibs and have never shortened them. They are very long.

Just had a look with just the nib on the riser and the current nib insert extends beyond the pressure button at full draw buy about 15mm. Hence the arrow can not bend at that point. Fortunately this is exactly where the second break off mark is. So I'll break off the last two segments of the nib and see what happens. Worth a try before I go out and spend money on a new set of arrows.

[Brocky]

Still dont get it, the spine is wrong, spend some money & save all of us the pain, oh the pain Will Roberson.

[geoffretired]

- Still with the solid pressure button, adjust your sight so that you are grouping around the centre of the target.
I have never used this method, but it does have a logical approach especially to the initial setting up.Most other methods start "a bit off centre shot" with a "medium" stiff button. Neither of those seem particularly clear starting points.
Having reached the stage quoted above, where could I expect the sight to be, in relation to the arrow, by the time the groups land where aimed?
I am guessing that well matched arrows would have a sight set directly above the arrow or close to, depending on the archer's string picture.
I am hoping to demonstrate this method at the club where I shoot. I would like to know as much about the likely results as possible so there are no surprises that I can't resolve.
If, for example, the sight setting ended up well to one side of the arrow, or the other, would that indicate a form issue rather than an arrow match issue?(the earlier stages would have already produced bare shaft and fletched arrows close together)

[Progen]

I believe it also depends on your string picture but I've had one setup where the sight aperture was quite a distance from the riser
(I have the string on the centerline of the riser) since the arrows were rather stiff for that setup but they still grouped fine at all the outdoor distances.

[geoffretired]

Cheers Progen. I guess you would expect the sight to be closer to the in line position with softer arrows or a string picture nearer the sight, yes?

[Bottom Dweller]

What effect does high FOC (Front of Centre) arrows have on tuning a recurve?

I have an FOC of 14.4%.

I have measured others FOC and it ranges from 7.3% to 16%.

Is there an ideal FOC for target?

[Brocky]

What effect does high FOC (Front of Centre) arrows have on tuning a recurve?
I have an FOC of 14.4%.
I have measured others FOC and it ranges from 7.3% to 16%.
Is there an ideal FOC for target?
Well you fall into the range you have stated.

[Bottom Dweller]

I found this very interesting discussion in another thread going back to 2003 which touched on FOC.

http://www.archery-forum.com/showthread.php?t=1182

FOC appears to be a contentious issue with strong opposing opinions.

My interest is in how FOC effects tuning. It seems to me that a high FOC will exagerate the recurvers paradox and possibly explains why some arrows will not "tune".

[Brocky]

I found this very interesting discussion in another thread going back to 2003 which touched on FOC.
http://www.archery-forum.com/showthread.php?t=1182
FOC appears to be a contentious issue with strong opposing opinions.
My interest is in how FOC effects tuning. It seems to me that a high FOC will exagerate the recurvers paradox and possibly explains why some arrows will not "tune".
Reading the articale provided by your juniors in another thread, Merv is the man to ask, just ask him :confused:

[whiz]

I found this very interesting discussion in another thread going back to 2003 which touched on FOC.

http://www.archery-forum.com/showthread.php?t=1182

FOC appears to be a contentious issue with strong opposing opinions.



Yes, but Joe Tapley is involved. Hence I refer to Marcus's comment about repeating an experiment 400 times until the result equals your hypothesis.

One correct bit of advice does not outweigh 400 wrong ones handed out with equal conviction.

[frommy]

[Bottom Dweller]

Hmm....

looks like I'm going to have to do some FOC experiments myself.

BTW there are some nice very slow motion videos of arrow movement from top recurvers on this site:
http://www.texasarchery.org/L1/HSV.htm

It is clear from these videos that the initial motion of a recurve arrow is complex and has many forces acting on it during this time. The initial rear movement of the arrow left (RH archer) due to the recurver release is significant. Interestingly the subsequent bend towards the riser is not centred and is less obvious than the next bend away from the riser which is more centred.

Edit:
For those interested in some of the mathematical modelling of arrow movement here is a good link to some papers on the topic by Bob Kooi.
http://www.bio.vu.nl/thb/users/kooi/

[manasf]

How to set the bare limbs of the bow? What is Tiller limbs?

[Borja1300]

I been reading all the posts and I'm little bit messed with one of the steps.



- Shoot some arrows and see where the centre of the group is. If the arrows are to the left then move the pressure button to the right, and vice versa.



If the group now, after re-adjust the centershoot putting the arrow a little bit foward of the center of the bow, is out of the center of the target, this shouldn't be fixed just moving the sight to put again in the center?

or when you say "if the arrows are to the left" you mean if the arrows groups in a eliptical and not in a round way?

Sorry for my english because I'm spanish.

[vincey]

I been reading all the posts and I'm little bit messed with one of the steps.



If the group now, after re-adjust the centershoot putting the arrow a little bit foward of the center of the bow, is out of the center of the target, this shouldn't be fixed just moving the sight to put again in the center?

or when you say "if the arrows are to the left" you mean if the arrows groups in a eliptical and not in a round way?

Sorry for my english because I'm spanish.

from what I understand, moving the plunger is better because its tuning it to the arrows as opposed to compensating with a sight.

arrows to the left means your group is to the left compared to the location of the group prior to making the plunger "something nice".

Someone can correct me if I'm wrong.