Pro's and Con's Carbon in the Limbs

[**DONOTDELETE**]

First of all... it's not the carbon that causes delamination... it's the core you are gluing it to that shears.

The tone sound is much higher pitched in a carbon / foam limb than carbon / wood limbs. The wood cores dampen the tome quite a bit.

The difference in feel has to do with the core mostly. A carbon /foam limb is going to feel different than carbon / maple cores.... but bamboo or yew wood has a very soft feel too.

 What about stability in a limb? Are carbon limbs more stable torsionally or anything else? How does that effect performance?

This question can be answered both yes and no. The limb stability is primarily controlled by the design. The difference in the limbs geometrical shape, and width profile is the biggest factor.

Type of carbon used is another huge factor, as well as the core material.  I've taken two identical sets of limbs, both at 50@28" and used carbon /foam & carbon /Maple cores & got identical speeds. Actually the foam was 1 fps faster....

But.... the maple cores were much better in vertical stability & torsional stability over the foam cores using matrix 45/45 weave carbon on both. The foam cores had a softer feel to the draw, but it had a much higher tone pitch.... i didn't care for the floppy feel of the foam core limbs at brace, but there are a lot of guys that love that soft feel of the draw.....

The best of both worlds for me was using bamboo cores, or even yew wood cores on that design..... you still get that soft feel in the draw, get better vertical & torsional stability....

I'd be willing to bet if you painted two sets of limb black and didn't know which was foam and which was bamboo cores, or yew wood cores, you'd never be able to tell the difference in the draw.

[**DONOTDELETE**]

Hey Bisch,

What did you think of the draw on those SS -ILF limbs i built for Paul?  Those things got some geometry going there. Carbon does't do anything to improve those limbs over all performance.

[dougedwards]

Even though these A&H limbs split at the glue lines and not actually on the carbon limbs I still suspect that the characteristics that make the carbon limbs faster, namely being lighter in weight and stiffer than most woods, could be putting additional stress on the limb as a whole.

After viewing the pictures, A&H feels that the bow must have been exposed to excessive heat to come unglued at the seams but I know that these limbs have not been exposed to such heat, unless shooting the bow in 90 degree temps qualify. I have put well over 2,000 shots through this bow since I have owned it and put over 100 shots through on the day that it let go while at full draw.

You can't blame me for being suspect of the carbon construction of the limb as I have owned over 30 bows in the last 5 years and nothing like this has ever occurred.
   

[Steve O]

And that ^^^^^^^^^^^^^ is the problem with buying a used bow.  You may have taken perfect care of that bow...the previous owner may not have.

I am no bowyer, but carbon is not magic.  If it is lighter than the material it replaces, the bow will be faster.

[LookMomNoSights]

I purchased an ACS a few years back....best bow I had at that time,  shot it well.  Craftsmanship i top notch!  Went to ETAR and shot ALOT of other bows....none of which had carbon....and found several of which that I thought I just liked the feel of better than my carbon ACS.  My most recent bow,  is a Zipper Nitro (carbon and foam) that I purchased new.  I was iffy at first,  not wanting it to feel like the ACS ....and it doesnt at all! 2 different animals entirely!  Because the carbon in the two bows is not the same.   I love my Zipper...and performance is not an issue, as other Zipper owners would agree.  Zippers are unbelievable!  That being said though,  I dont think carbon is a must for me by any stretch....and I actually like the feel of a bamboo, maple or elm core the most....in terms of how the bow feels through the shooting cycle.  This is just my feelings on the subject.

[hybridbow hunter]

I had a brand new ACS Bow with delamination 8 months after purchase. Bow was very fast and bow grip really nice.On replacement limb set wood overlays at bolt level delaminated after 2 months. Customer service from A&H was first class but it was too much hassle for me.
 Then I purchased my border  BD HEX6 wood core and tillered to zero. That bow was VERY fast and vertical and torsional stability second to none hunting bow on the market. But it was noisy and didn't shoot better than my other glass bows. Limb exploded 11 months after purchase. I was very disappointed as I was firmly believing in the toughness of these new HEX6 limbs advertised by the firm and despite Border customer service was perfect I planned to sell the bow with new limbs as soon I get them.
Once I received replacement limbs few weeks later, I noticed new set was tillered +1/8" and 1# lighter. Using same string and nock height I was shooting on previous I really discovered a NEW bow and my shooting improved to a next level at long range, plus the bow was MUCH quieter. I shot 3 or 4000 arrows before I decided I could give another try and I did my Botswana hunt with it although I backed up with second bow.
Actually it shoots same arrow 1 fps faster than my fastest glass recurve ( RER  the Vital) although 5# lighter than this RER at full draw.
Am I confident on bow reliability over long time? NO ! And plan to buy identical back up limb set ( I know I am nut...) but I like now this bow very much.
When you buy this type of bow you must probably accept to pay a kind of tribute to reliability with higher odd for breakage, the same way when you buy a Ferrari car.

[dougedwards]

Originally posted by hybridbow hunter:
I had a brand new ACS Bow with delamination 8 months after purchase. Bow was very fast and bow grip really nice.On replacement limb set wood overlays at bolt level delaminated after 2 months. Customer service from A&H was first class but it was too much hassle for me.
 Then I purchased my border  BD HEX6 wood core and tillered to zero. That bow was VERY fast and vertical and torsional stability second to none hunting bow on the market. But it was noisy and didn't shoot better than my other glass bows. Limb exploded 11 months after purchase. I was very disappointed as I was firmly believing in the toughness of these new HEX6 limbs advertised by the firm and despite Border customer service was perfect I planned to sell the bow with new limbs as soon I get them.
Once I received replacement limbs few weeks later, I noticed new set was tillered +1/8" and 1# lighter. Using same string and nock height I was shooting on previous I really discovered a NEW bow and my shooting improved to a next level at long range, plus the bow was MUCH quieter. I shot 3 or 4000 arrows before I decided I could give another try and I did my Botswana hunt with it although I backed up with second bow.
Actually it shoots same arrow 1 fps faster than my fastest glass recurve ( RER  the Vital) although 5# lighter than this RER at full draw.
Am I confident on bow reliability over long time? NO ! And plan to buy identical back up limb set ( I know I am nut...) but I like now this bow very much.


  When you buy this type of bow you must probably accept to pay a kind of tribute to reliability with higher odd for breakage, the way way when you buy a Ferrari car

You are probably right about that last statement and a distasteful lesson for me to learn. I don't mind taking a chance on a $400 used bow but one that will cost me an additional $750 to make operational after a material break down is not acceptable to me and has changed the way I think about traditional bow purchases in general.

 Doug

[Adirondackman]

[ron w]

Chevy was putting F.I. on their cars long before 1969........     I'm not going with carbon in my new bow. I just don't think I will see the benefit for the cost at 15-18 yards.

[monkeyball]

i am not talking about bows now,but i know my carbon arrows far outlive any wood arrows that rode in my quiver. That says something to me.

  As far as toughness goes,once again not talking bows,but I looked at an all carbon mountain bike,rims included. The only thing that kept me from slapping down the cash was how much I was going to have to slap down! Carbon is tough!!!!


                                         Good Shooting,
                                                           Craig

[TxAg]

My only experience is with carbon Centaurs. I've shot a few different models, but my triple carbon is sweet. So is my buddy's.

[Brandywine]

Hello:
For perspective:
After owning and still having many fine longbows and recurves built by highly regarded bowyers, all praised here, and having heart-to-heart discussions, here's a summary of a few years of their experiences:

All say in one way or another that the amount of carbon material used by our entire industry is so small that no carbon supplier will warrant detailed quality control.  Each of our respected bowyers has been stung with erratic qc, even from the same sources that aircraft wing builders rely on!  One frustrating example involved the layup missing a crucial bias-ply layer, leading to limb twisting.  

By far, the greatest cause of delaminations in both carbon and non carbon bows is temperatures way above the tolerance limits of the epoxy resin tolerance, approximately 140 degrees.  When a delamination event arises AND the owner is candid, if he even knows, that the bow has been in hot environments, the bowyer has a good idea what caused the materials, not fabrication, failure.  The carbon was not the cause.  

My experiences involve twisted limbs and gooey resin bubbling at seams.  EACH WERE TRACED TO SHIPPING IN HOT WEATHER.  One sat in an exposed FEDEX van with outside temp's approaching 100 degrees, for four days over a three day weekend.

Now, I only have bows shipped during cold seasons.

Each of the fine bowyers involved was as nice, understanding and responsive as anyone could expect and I've done more with each after the events.

I cringe at having to transport ANY bow into hot climates.  Just sitting on a loading ramp can cause too much exposure.  140 degrees is too easily reached in auto's, trucks, etc.  

Some bowyers that don't like carbon have indicated noise issues, but agree that it can be from shooter induced variables.  Others simply say the few FPS gained are not worth the headaches.  All agree that the temperature demon applies to their, NON CARBON bows, too.
Respectfully,
Kevin

[dougedwards]

I think that a good question would be:

Do you feel comfortable taking a bow into the hunting field that has carbon in the limbs?  

Do a survey on that and see what you come up with.

[overbo]

Heck yes I feel comfortable. I've had a triple carbon bow I've owned since 2008 and have tons of arrows thru it. Just because you had a failure doesn't mean that every carbon limb bow is bound the same. I've had glass bows fail too. Any bowyer that has been building for some time has had failures. If they tell you other rise, I would move on to the next one.

[nineworlds9]

Kirk and Brandywine gave some informed and thoughtful answers.  

Kirk especially is worth listening to on this subject, for obvious reasons.

I have shot quite a few bows with carbon construction.  I can tell you pretty well that it is the base design of the bow that yields the speed..it either is a quick shooting design or it is not.  In my experience the carbon bows are not any louder, just have a different tone, some are quieter.  From what I have deduced the primary benefit is torsional stability as well as durability and shot consistency.  I would gladly put up a triple carbon Centaur or Habu up against anything out there in that regard.  To me when I shoot the well designed bow or limb that integrates carbon thoughtfully into the construction will be a more consistent shooter in regard to windage/ left to right impact once tuned properly.  This seems related to limb stability during the draw cycle.  

All this alarmism about carbon adding to fragility is a bunch of malarkey.  The big ILF limb manufacturers that build gear for Olympic style shooting have been using carbon weaves in the limbs for decades now with fine results.  

Just slapping carbon on the back or into the limb core without giving it zero thought or testing is not going to yield an instantaneously 'better' bow.  That being said, my current favorite bow has no carbon in the construction, just a center strip of Uniweft in between the bamboo lams, and the bow is a shooter.

For me the biggest differences I notice other than the potential gain in stability and a few fps speed are the draw cycle feel and TONE of the shot.  That is why I recommend you try a few carbon designs used before plunking for the new stuff.  

That being said, the latest new bow for me with carbon is the double carbon Schafer I recently acquired.  The carbon does nothing but improve an already great design.  Zero doubt Dave Windauer thought it out long and hard, with lots of testing, before offering it as an option.