Youth arrow questions...

nbuuifx

Member
Why are arrows so complicated!?

I had the perfect arrows set up for my daughter. She has been using the weakest tributes (1214).

They've been the best tuned arrow she's ever used. (She got her junior master bowman with them.) They were a bit annoying as they are so weak that they get bent easily but tuned so well. Unfortunately she did what most kids do and had a growth spurt. So they became too short.

They were approx 22" and she is pulling 20.6lbs. So at that they were off the chart.

She'd got to the point where she was scared of doing a proper release in case she pulled it off the rest. So for a few weeks she has shot using some acc arrows that she had that are too stiff. She had some left over shafts from the 1214s so I have cut them as long as possible so the clicker is at the end of the clicker extension. These are now 24.25".

The new longer ones fly terribly, land at an angle, are hitting the rest and taking chunks out of the lower hen fletchings (hitting the magnet on her rest).

So I take it they are too weak now. This fits in with the chart, as she had just moved into Y2.

She has been steadily increasing in poundage. She shoots at least 500 arrows per week.

I've now got to work out what will be best to buy next. Obviously due to the lockdown I don't envisage any competitive shooting until the indoor season, so she is just shooting at home for practise. Mostly short range.

Group Y2 only has 1413 arrows which are a 2.036 spine. These should be technically the correct arrows but they may not last long and I imagine they will bend easily like the 1214s.

The Y3 and Y4 groups are a bit strange. I'm sure there is reasoning behind it but they have the following...

Y3
Inspire 1400 (1.400 spine)
75 1416 (1.684 spine)

Y4
ACG 1500 (1.5 spine)
ACC 2-00 (1.5 spine)
Inspire 1400 (1.4 spine)
75 1416 (1.684 spine)

As you can see both the Y3 ones are repeated in the y4 group.

The reason that I'm wondering about the higher up groups is that the spare arrows that she was shooting are the ACC arrows from group Y4. They are approx 23". They act a little stiff but they shoot better than the longer 1214s. They also stay straight much better than the 1214s. I also have 6 shafts that I didn't use from that set. I don't know if they are uncut but they are certainly longer perhaps 25".

So my questions are...

Why is there a 1.400 spine arrow in y3 but then the 1.500 spine arrow are in the next group? I'd have expected them to be the other way round.

Given my situation and the fact that she just needs to keep shooting at the moment, what would you do?

I could take an inch off the longer 1214s, which would bring the clicker onto the riser. This would make them right on the chart. Perhaps that would be worth a try for now?
 

Cereleste

Supporter
Supporter
They're so complicated because we want the frequency at which they flex (determined by the spine, length, point, nock, fletches) to match up fairly closely with the amount of time it takes for the string to get from full draw to brace height, which is determined by the bow, the arrow weight, the archer's release, the phase of the moon, etc. We can measure some of these very easily, some less so, and some are just wild guesses unless you have £10k of cameras. Despite all the fuss about spine, there's very little information about the degree to which the correct spine arrow gives the best scores or whether one category stiff or weak is actually better. Hence trial and error being the easiest and cheapest method of getting a satisfactory result.
The 1.400 spine is a pure carbon shaft while the 1.500 is an aluminium/carbon layered shaft, and you didn't even mention the pure aluminium shaft with a 1.684 static spine! Each has a different density and material stiffness (Young's modulus, not related to the shape of the arrow), which means that they bend at a different speed. But the difference in density means they'll spend different amounts of time from release until they leave the string, so when "matching" up the shafts with the bows weights Easton's ended up with different spines of arrow working well with the same draw weight and arrow length. For some reason that involves some fancy models Eason has and the rest of us can only approximate, the combination of density and stiffness that you get with an ACG or ACC results in a bendier spine than a pure carbon Inspire and a stiffer spine than a pure aluminium XX75.
Also, Easton combines the 20-24lbs and 24-28lbs youth categories into one group in the adult chart. If you look at the different draw weight categories on the adult chart, the range of weights gets smaller as the draw weight increases, so the arrows are more sensitive to being the correct spine when they're being pushed faster by the bow (much less leeway for them to bend a bit too slow or fast and still get away with it).
That's plenty for your initial question, but happy to elaborate if you/she are interested - I got into this area towards the end of high school and it steered my interests in uni a fair bit. There a quite a few publicly available research papers on the topic though at that age most of the maths was still a bit inaccessible.

As to what would I do, how far is she shooting? The bending that an arrow does has an initial amplitude of maybe an inch at the most and it takes about 15m before the bending dies away and the fletches have enough time to drag the arrow towards straight. So shooting an unmatched arrow looks much worse at short distances. For example, at 60m I can shoot bareshafts of my regular spine of arrow into the centre of the target, and bareshafts that are two groups stiffer land about a foot left and bareshafts that I've made about a group weaker land about a foot to the right, though all group sizes are about the same and all arrows are pointing straight into the target. When I shoot the same arrows at 5m indoors, the correct arrows do the same but the stiff and weak ones point up to 15 degrees left or right, and the angle at which they point changes rapidly as I increase my shooting distance. Essentially, it looks like a complete mess on the target. However, the group size of the different arrows is not noticeably different, at least not after a few ends.
The window for "ok arrow flight" is much larger on the stiffer side as it's not as prone to the clearance issues you're experiencing, so I would definitely take an inch off the longer 1214s and use cornflower/dry shampoo/lipstick in the arrow rest area to see if that's fixed the clearance issue. She's only going to keep getting taller so if the 1214s are too weak now they'll just get worse as she grows so might as well try to get use out of them now. If she can move her clicker out enough to shoot the uncut ACCs (depending on the type of clicker you can jury rig various clicker plate extenders or sight mounts with things lying around), I'd also give those a go. Maybe use a target face and see whether she gets better groups from the ACCs or cut 1214s by doing a few scoring rounds with each on different days to account for good/bad days, and decide where to go from there. As long as the arrows aren't banging into the bow on the way past (which can add inconsistency and increase group size), I wouldn't worry about their angle in the target unless seeing them at odd angles affects her focus (seeing the shaft at an angle puts me on edge even when shooting multi-spot targets where there's no risk of the next arrow hitting and damaging the shaft).
I'd be wary of the 1413 which have an even smaller wall thickness than the 1214 and so will be more susceptible to dents from arrow impacts.
 

nbuuifx

Member
Thank you for the in-depth answer!

That is useful to know about the 1413s having a thinner wall. I'll avoid them.

I think I'm going to cut those longer 1213s down to the same length as the slightly stiff ACC arrows. That way she can shoot both using the same clicker position and hopefully it will make the 1213s stuff enough to shoot without contacting the riser.

If the 1213s are still too stiff, then I might add well get rid of them all as they will be useless to her now.

I could make up some of the spare acc shafts as arrows to try and see what they fly like at full length. Could just test without the clicker. We do have a sight mounted clicker somewhere that could be used but to be honest if shortening the 6 1213 arrows does the trick for now, then along with the 6 or 7 acc arrows that she is already using she'll have plenty to get her through to the winter and I can relook at the options then, at which point she'll have probably grown and her poundage will probably have gone up too.
 

Cereleste

Supporter
Supporter
For aluminium arrows, the numbering system is: outer diameter in 64ths of an inch then wall thickness in thousandths of an inch. So 1214 is 12"/64 diameter and 0.014" thick.
 

mbaker74

Supporter
Supporter
I have just had a look at this based on the current, 2020 Easton target chart....

1214 Tributes are Y1 group, a 22" arrow and 21lb draw weight from the chart puts you in Y1 group.... Making these same arrows 2.25" longer moves up one group to Y2, so the 1214 spines will be far too weak. Taking an inch off the 1214's will still leave them an 1 1/4" longer than hte arrows that tune / fly well, so they will still be too weak.

The ACC arrows (2-00, so y4 group) you have in 25" would suit a draw weight of 24-28lb from the chart. They would definitely be the best option from what you have right now, as stiff arrows can generally be tuned in reasonably well, but weak is weak.... especially if you have a sight mounted clicker

What you do next I guess is dependant on where you think she will go with pondage increases and how soon....

Personally, I would stick with the ACC's you have at 25", as it soundsliek she will very quickly grow into the additional length ( only needs 0.75" to get back onto a riser mounted clicker, and if shess shooting that many arrows she may well build up 3-4 lb's in draw weight quite quickly too.

Another option, if you can shoot all carbon arrows, would be to go for the 24.25" long, but in Carbon 1's 1800 spine but that would not cover a growth spurt and a poundage increase....

One other suggestion, you can often pick up short, very soft spines arrows on Ebay very reasonably, as kids do tend to grow out of htem very regularly....
 

nbuuifx

Member
Thanks for the input, I might as well try the 1214s a bit shorter first as they are useless otherwise. I'm going to cut them to match the already cut acc arrows so she can shoot a dozen with the clicker in the same position then collect.

Carbons are a possibility but would only be on indoors as we aren't allowed to use them outdoors at our club and many of the competitions.

I'll give the longer acc arrows a try too.

Not so keen on used arrows, these aren't hugely expensive and as above these things wall ones bend so easily that I think it would be too much of a gamble buying used.
 

mbaker74

Supporter
Supporter
It was more if you were looking for some more ACC's to try at different lengths, its very easy to see any damaged ACC arrows just by flexing them, and by buying off ebay, you can try multiple spines and lengths, then when you know which you want, go buy a brand new set and sell on the used ones for roughly the same money you paid for them.....
If you cant use them outdoors, forget the Carbon 1's.... I would stick with the ACC's and just extend he length till they tune, then as she grows they will move in naturally, and as she goes up in poundage you can shorten them to stiffen.
 

nbuuifx

Member
Just to follow up on this,

I cut the 1214s down by an inch which doesn't give them long to last and they did tune in - they aren't perfect at short distance but they are better and are not contacting the riser now - the only issue that I had is that 4 of them were quite badly bent during the few test shots. They all landed in the foam but the contact with the riser or the bad angle of landing had bent them. Do the arrow straightening tools work? I've seen some that look a bit like a pair of pliers with a couple of wheels in which roll up and down the shaft.

The ACC 1500s at the exact same length as these are too stiff but shootable.

I've not tried the longer ACC arrows yet - but will do when we get the opportunity to test them out at a longer distance.

I've just been trying to keep her going at the moment whilst we're shooting in the garage to keep her strength up. So she has had a mixture of ACC and Alloy arrows.
 

Cereleste

Supporter
Supporter
The only arrow straightener I've used was the large kind with two sets of bearings about 10" apart and a dial gauge in the middle and a handle that you push down when you're centered on the bend of the arrow. You can definitely take out bends, especially large sharp ones with this kind of tool, it'll make a dead arrow fly straight again, but it's unlikely to group 100% as good as before it was bent. From what I gather, the pliers kind is a bit less effective as you can't target the bend. It costs about as much as 5 xx75 arrows though and only good for aluminiums, so the utility might be pretty marginal unless she's likely to have another set of aluminiums at some point.
 
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