what is it about carbon foam?

KidCurry

Active member
. I shot the Uukha set up against hoyts top of the range, which is initially what I had set my heart on, and walked away with uukha.
Out of interest what range of Uukha limbs were you shooting against the Hoyt. I shoot X Tour which get me (barebow) point on gold at 90m three fingers under. They were really cheap :) I would prefer to shoot Uukha if I don't have to pay £500+ for them.
 


LionOfNarnia

Supporter
Supporter
Although I'd find it difficult to try & put into words, I think I can visualise why a 'foam-like' core might be the best solution.

But I'm a tech-fan at heart anyway, so 'gimme graphene!'
 


geoffretired

Supporter
Supporter
If you keep the two layers apart, you make each one work harder at its given task. The stretchy one stretches more the compressive one compresses more. Keeping them apart with something light helps with speed, I guess. A wood core will be light. Foam I would think is lighter but it needs to keep the laminations apart. I could imagine lots of tiny cylinders acting like hollow columns would be the sort of thing.
 


Timid Toad

Moderator
Staff member
Supporter
Fonz Awardee
Ironman
Yes. The non-working bit needs to be as light as possible. Overall mass of the limb does make a difference to the speed the limb can move at. So no dead weight.
 


Stretch

Member
There are some spurious points floating in here but for me the biggest difference between foam and Wood cores is the feel. However, that does vary across limb builds. I have shot foam cores extensively but ultimately the limbs I have always liked the most have been woodcore. Purely based on feel. Wood “tends” to be softer and quieter with less vibration. But ultimately limb build is a huge factor in that equation too.

Then of course not all woods are created equal. Cheap limbs will be “wood” more expensive “Maple”, more expensive again “hard rock Maple”, and then some form of impregnated wood - which is basically reinforced wood. You get good limbs and bad limbs in all of these categories.

Personally I don’t like the feel of any hyper-recurved limbs. At a 32” draw they just feel wrong to me. The way the weight bulds just does not suit me. I notice that Ukkha are also recommending very long limb lengths per the normal recommendation. Nothing against Ukkha, they are just not my thing but might be yours.

Very few international archers are paid by bow manufacturers (unless they work for them) - some but not many. Many get their bows for free - from the manufacturer they choose. Some buy there own. The idea that nobody shoots Ukkha at top level because Ukkha don’t pay people is spurious - firstly there are a whole bunch of top archers shooting Ukkha (Mexican and French jump to mind). But secondly winning is the driver of anyone who competes at this level - if they thought they would win more with Ukkha they’d sell their granny and buy some. Most top brands do pay contingency for big wins/podium places. Personally I think those rewards are hard earned.

So back to the original post. If it was me I’d try to find W&W EX Prime and EX Power and compare two very similar limbs with comparable quality build and material quality. That would tell you what your preference is. They are also a limb of unquestionable quality and performance. Then I’d buy a good secondhand pair to my preference. Any older top limb from W&W, Hoyt, MK etc will be in your price range. (Just be aware tha Hoyt bamboo cores do not feel the same as a woodcore).

2p

Stretch
 


Whitehart

Well-known member
Archers are a conservative lot even internationals and do not venture far from what they have always known and their choices are no different when selecting other archery accessories - tabs, arrows even vanes & strings - Money in archery is very poor, but if you get $3000 for winning the AGB national tour with W&W or $2000 with Hoyt and nothing with Fivics or uukha this does and has had a bearing on an archers choice. Manufactures also help national governing bodies and money can be lost, or have to be replaced by the incoming manufacturer for a NGB to change.

FUD (Fear Uncertainty and Doubt) from the known is always the overriding factor.

But at the highest level it is always hard work that puts the archer where they are.

The majority of uukha limbs sold have a standard curve it is only the VX+ and VX1000 that have the Xcurve. Ironically IMO it is not just the international archers that can benefit most from the uukha USP's. More so it is Club/County archers that cannot shoot the high draw weights or practice everyday - but still want to be competitive at club, county and national level. In this instance technology can be a wonderful thing.
 


mbaker74

Supporter
Supporter
Out of interest what range of Uukha limbs were you shooting against the Hoyt. I shoot X Tour which get me (barebow) point on gold at 90m three fingers under. They were really cheap :) I would prefer to shoot Uukha if I don't have to pay £500+ for them.
I think it was the X Tours I was trying, compared to the VX1000 uukha limbs (the non super recurve version, the numbers have changed now..), which were pretty much the same price to be honest....
Hoyt Velos are £705 at Merlin, Uukha top of the range VX+ are £740 so not a lot of difference price wise... only difference really is that the Hoyts are much more available second hand....
 


Rog600

Member
Under £200 gets you own-branded carbon foam limbs from Merlin made by ahem, a well known company, and their marked weight is measured with limb bolts 'out'; read into that how you like. I've shot 1200+ with them. Just throwing that out there.
 


I went with KAP Winstorm carbon/foam limbs, 2019 edition. They were well under my budget so - bonus!
There's no leaflet in the box or anything, just the limbs. I was hoping there's be something, preferably with suggestions for tiller because I don't know. But there wasn't so I just popped them onto the riser. Didn't adjust anything, used the same string, was very lucky that the nocking point was ok. A couple of dozen arrows and it's obvious that they're very good. Not about to do a detailed review, especially since I now have to google about the tiller but initially at least I am very impressed with carbon foam!!
 


Andy!

Member
Dave, you wont see them on the main stage target archery stuff on YouTube, as Uukha don't pay the big boys to use their kit.
They don't actually get paid to use kit. It's the extra you get if you win with it.

If you're an excellent archer, the kit makes very little difference. You're going to win. So you have a choice.
You can win a medal with brand x limbs, or you can win a medal AND get several thousand dollars from manufacturer Y, because you used Y's limbs.

Archers put in a LOT of effort for very little financial reward. Contingency money is a significant incentive if you're going to get it for free. Edit. Stretch has already covered this. So did Whitehart.
And they're ABSOLUTELY correct, of course.

If we use two laminations, we can choose the outer for its ability to withstand stretching and the inner for its ability to withstand compression.
Yes. AND if we make them out of carefully chosen and constructed materials, they can be incredibly light and incredibly strong.
They just have to be kept in the right place and they'll do all the work perfectly, right up to the limits of what they're able to repeatedly withstand before crapping out..
So if the tension and compression layers are doing absolutely ALL the load work, then the shear layer does bugger all.


If the right materials are chosen along with the right thickness of each material, then the glue line can be subjected to being bent but not stretched or compressed. I think that is like the self bow of yew having the right thickness of heartwood and sapwood so the two layers both get subjected to just one of the forces. I would guess that a middle lamination could be used to good effect
The middle laminations tend to actually be over engineered and add more weight than necessary. Nobody complains about a bow that doesn't break easily, however they DO complain about longbow kick. That's what happens when the limbs are heavier than they need to be. The sad thing about longbows (and flatbows) is that they aren't supposed to get the same limb technology as highly developed recurves. It's also much much harder to take a self bow to the point where they're finely tuned limbs. They just aren't reproduceable due to the materials variability.

Also, nobody likes it when they break them during manufacture.

If you look though, you'll see people experimenting with carbon laminations as early as twenty years ago and making some really sweet flat bows that were of significant performance increases over regular construction. The uproar from the traditionalists expected to compete against these bows was absolute gold.

As with the feel of limbs and being able to relate this to core material, the main issue is that you'd need to have limbs with identical top and bottom laminations, kept apart by different core materials.
And no manufacturer does this.
So different limb feel might be attributed to anything that someone can discern as being different and they can't be proven right or wrong because actual evidence is impossible to collect.

As for where limbs make a difference, there have been considerable theories over the years, however one appeals more than others to me.

When you're beginning, everyone is crap. Limbs don't make that much difference.

When you're at the absolute top of the pile, everyone is excellent and everyone has top of the line limbs.. So there's not much difference to be seen there.

However, in between these two extremes there will be people of similar skill. Let's say that they have identical draw weights and the same arrows. Over a competition, the nicer limbs throw faster arrows and are smoother through the clicker. The other limbs stack and are slower. So they're harder to shoot consistently and the arrows spend longer in the air, giving them more time to be affected by wind drift. There is even the measurable performance increase of being confident in one's more expensive gear. It's a REAL thing. (It also works in reverse)

So where this limb difference could logically be expected to make a difference is where it probably does. Mind you , nobody collects this kind of information and it comes about by excluding other factors at the beginner and elite end.

As a data analysis comparison, it was long considered that there were archers who were matchplay specialists. Individuals who were steely under pressure and who would beat better archers in matchplay purely because they were able to hold onto their game a HEAP better. And of course, we all saw that kind of thing happen, so it was a theory which met with some acceptance.

Then came James L Park's analysis of 14 years worth of high level archery matchplay. A study called "Winning major international target archery competitions"

It showed that the majority of winners came from the top eight places in the ranking round.
This wasn't really a surprise. These are the archers who are good archers, regardless of what pressure is put on them. It's WHY THEY ARE AT THESE COMPETITIONS!

But what about competitions where there AREN'T the world's best archers? Do these results still apply?

Consider your club archer who is super comfortable with a 1440, who all of a sudden has to make every arrow count in a shootoff.
You've all seen someone lose their shit and totally collapse. This is NOT a characteristic of a seasoned world cup competitor and is by definition exactly why they're NOT a seasoned world cup competitor.
And there are far more archers who aren't seasoned competitors shooting shootoffs at club level events. This data isn't being analysed. The archers aren't at the same level. There is logical reasoning to believe that at the middle level, there ARE matchplay specialists that outshoot typically higher performing archers in competitions with more arrows.

And when you extend the logical thinking, where do the top level competitors come from? The archers who lose their shit or the ones that keep it together? That kind of mental toughness doesn't magically appear once you hit 1350.

I'd like to put it out there that the archer is the thing that makes the most difference. Human nature will ensure that archers will try and make up for this by spending money. Confidence buys points, until of course, everyone is super confident.
 


Emmadragon

Supporter
Supporter
Just a thought...does there come a point, though, where an archer is limited by their equipment, so can only improve with 'better' equipment?
 


LionOfNarnia

Supporter
Supporter
That's what the manufacturers, and the bowshops, want you to believe anyway ;)

I suspect a large part of any improvement is purely psychological - as Pat Huston said:

"cool-looking stuff always shoots better."
 


Stretch

Member
Just a thought...does there come a point, though, where an archer is limited by their equipment, so can only improve with 'better' equipment?
Yes, definitely but not hugely. Many, many years ago when I was at Uni and all we shot was Portsmouth, I shot my beginner bow (£80 Korean thingy) and arrows to 539, I shot it over and over, sometimes a bit under.

I bought a decent mid-range bow, dipped to 519! Then 552 and then into 570s in less than a month. Biggest factor was probably the arrows. Outdoors arrows and limbs are the primary need for “better” but most people buy risers because they look nice.

Does someone shooting < 500 benefit from a £1500+ bow. Only at ego level. But the difference between low end and mid range is pretty huge. Difference between mid-range and high-end is much less and tends to focus on a specific criteria or two that may work for you. Although frequently it does feel nicer, it just doesn’t necessarily score much better.

2p

Stretch
 


Andy!

Member
Just a thought...does there come a point, though, where an archer is limited by their equipment, so can only improve with 'better' equipment?
Only if the equipment's level of variation is contributing to the archer's level of variation. Typically, bows are incredibly consistent, yet myth, legend, movies and advertising all put the requirement for accuracy on the Bow. Then people try and ignore the archer, or just consider the archer a certain known quantity who will be "good with any equipment"

Then we come to the arrows.

For a reason that continues to escape me, despite archery being a marksmanship sport, and marksmanship requiring consistency to be predictable, the general public refuse to consider that the arrow is a different one every shot.
This reasoning is reinforced in every depiction of archery in popular culture. There is no movie, book, TV series or comic which ever bothers to educate us to the fact that accuracy with archery relies on all parts of the system being consistent. Actually, I just recall that I listened to an audiobook where the main character did actually grade his arrows and prepared them to be shot according to distance as the enemy closed because I remember being stunned by that little detail.

So we note that archers are prepared to buy cheap arrows. We know that perfect repeatability of a system can't be maintained with the arrow changing every shot, yet archers are resistant to attaining this absolute requirement for accuracy. Actual published scientific research shows that arrow straightness is critical in shaft and nock alignment, to the point where manufacturing tolerances means that some arrows are impossible to gain maximum points with, because their variations from perfect make their impact points wider than the ten ring is.

But it's okay, because archers have developed philosophy to deal with this. "I can't shoot well enough to notice the difference with expensive arrows" and then cling to the concept of a "forgiving bow" which somehow can sense the intent of where the target is and direct an arrow to it, regardless of where it was pointing when it was loosed.

At least in the movies, marksmanship with rifles sometimes gets a nod to quality ammo and the hero will either handload it with great care, or somehow mention it's special.

If you want a real slap in the face to show you how archers cling to myth, go to any other precision marksmanship sport and explain the concept of a forgiving bow and ask them what a forgiving setup is in their world. You will get blank stares, disbelief and laughter.

Forgiveness is a concept confined to archery.

I've been writing for the last five years on how archery is it's own worst enemy because of how the public thinks about it, vs reality.

You only have to look at how even barebow archers sometimes regard a target bow as "cheating" to know that unrealistic attitudes are well entrenched within participants.
 


geoffretired

Supporter
Supporter
What a great post!
Forgiveness is a concept confined to archery.
May you be forgiven for pointing out all my weaknesses. heehee
 


KidCurry

Active member
Forgiveness is a concept confined to archery.
Ahhh... no it's not. Fly fishing rods range from forgiving to quite critical. Stiffer, faster rods are not so compliant with poor technique. Interestingly, carbon, epoxy and fibreglass are also key ingredients in fly rods as well as archery limbs. I have an old kevlar rod which is superb. It's odd kevlar didn't make it into limb technology, that I know of, although it did make it into bow string technology.
 


Andy!

Member
Ahhh... no it's not. Fly fishing rods range from forgiving to quite critical. Stiffer, faster rods are not so compliant with poor technique. Interestingly, carbon, epoxy and fibreglass are also key ingredients in fly rods as well as archery limbs. I have an old kevlar rod which is superb. It's odd kevlar didn't make it into limb technology, that I know of, although it did make it into bow string technology.
Yep. I fly fish too. Have been fly fishing in Canada and Florida as well as all around Australia. Forgiveness doesn't mean the same thing in a fly rod.
(Now doing UK style carp fishing and only just got home from river fishing in Yass, where I caught an 83cm Murray Cod on corn. Unfortunately, no scales were in the kit, so we guestimated him at between 8 to 10 kilo. We did have a tape though. We caught 4.83 metres worth of fish. Smallest was 63cm. )
 


LAC Mark

Member
Ahhh... no it's not. Fly fishing rods range from forgiving to quite critical. Stiffer, faster rods are not so compliant with poor technique. Interestingly, carbon, epoxy and fibreglass are also key ingredients in fly rods as well as archery limbs. I have an old kevlar rod which is superb. It's odd kevlar didn't make it into limb technology, that I know of, although it did make it into bow string technology.

Kevlar did make it into Limbs, I have a set of SF ultimate pro, and they are Carbon, Glass and Kevlar.
From what I understand they were a rebranded version of a Win & Win limbs, but can't remember which ones.
 


Rik

Supporter
Supporter
Just a thought...does there come a point, though, where an archer is limited by their equipment, so can only improve with 'better' equipment?
Depends. Even beginners kit is better than a lot of archers. There was a test by the Frangillis a few years back - Michele shot Fita 18s with a wooden trainer bow (matched shafts and set up right) and could manage 550 scores with it, IIRC. He had (has?) the world record at around 597/598 with his normal kit... But the difference between "average archer" kit and top-flight is going to be a lot smaller than that. Most people seem to be limited by themselves.
 


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