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Arrows and Arrow Shaft Facts of the Matter on an Engineering Perspective

1.5K views 12 replies 8 participants last post by  Shorty  
#1 ·
First let me say this post has no brand name associated with it. This is merely to educate those in this sport that may have some confusion on the available selection of shafts themselves or the massive selection of ready made "off the shelf" pre-built arrows. This information shared is the combination of many months of R&D designing, lab testing and final performance out of a crossbow. The testing criteria was based on carbon type, carbon grade and the wrap & roll process. This does not include extrusion process.

Manufacturing Process:
Cutting of the pre-preg material was completed on state of the art cutting equipment so that the sheet width is +-.002" accurate Piece/Piece. This is critical for the final shaft spine achieving match grade spine deflection. The main focus here was to eliminate the need for, say, two dozen shafts required to achieve one dozen shafts with perfect spine matching whereas normal and customary "shearing" on the material prohibits that accuracy. Shearing can produce "frays" of carbon fibers affecting deflection values. This new proprietary process provides a razor edge promoting consistent width, no fraying.This is more critical for woven/weave material than that of plain fiber (more on the differences to come)

The Mandrel rolling process, regardless of woven/weave or plain fiber has also been improved whereas the force applied while wrapping the pre preg film is adjusted relative to force value: "Closed loop" process. This improves the degree of starting point and end point of the wrap that is critical for layered seam match.

The noted processes can achieve shafts that are +- .002" deflection consistently and eliminates the "problem child" shaft that has distinct deflection error. These processes also increase hoop strength accuracy that further promotes shaft performance.

All that said, lets talk about the two main two options you the shooter has and the expectations you may want/need. Advantages/Disadvantages between the two.
Plain fiber Shafts:
Normally the lower cost shafts you will find on the market (outside of some brands that demand high cost). The fibers run linear down the shaft and easy to recognize for the fact you see no weave.
Advantages: Ability to manufacture a very stiff shaft WITHOUT increasing OD like with woven/weave shafts. Currently have manufactured plain fiber shafts that @ .346" diameter ARE currently the stiffest manufactured providing the least deflection to date. This stiffness allows those bows that cannot tolerate larger diameter woven/weave shafts. (mission sub series for example)
Disadvantages: Plain fiber shafts do not have the wall strength as that of woven/weave shafts. Some shooters accurately report where the shafts split or splinter as the shafts experiences many target impacts or striking and animal. This is directly due to the fiber orientation being linear down the shaft rather helical in a woven/weave shaft. Crush testing on many brands of plain fiber shafts indicated as much as 40% less collapse value as that of woven/weave.

Woven/Weave Shafts:
Normally slightly higher in cost due to carbon manufacturing process. The carbon fibers are normally woven and run in a helix down the shafts providing excellent torsion strength.
Advantages:
Extremely long lasting regarding durability. High level of cosmetic finish for those looking for a "pretty" shaft.
Disadvantages:
Difficult to achieve stiffness without increasing wall thickness. These shafts require as much as . 360" diameter to match that of .346" diameter plain fiber stiffness.

Conclusion:
Plain fiber shafts perform as well as woven/weave if indexed properly. HOWEVER, plain fiber shafts suffer from short term life due to carbon degradation. Woven/weave shafts perform as well HOWEVER last 4-5 times longer before experiencing any degradation/accuracy issues. HOWEVER, if the shooter is looking for small diameter "stiff" shafts then plain fiber is the way to go.

As you can see the decision is based on what you want/need relative to your bow. Standard diameter shaft with stiffness, shoot plain fiber knowing the life of the shaft is much less before degradation sets in and accuracy will suffer. Woven/weave shaft if you can tolerate larger diameter to achieve stiffness and experience much longer shaft life.

Whichever you decide, invest in a quality shaft/arrow that satisfies your expectations. $29.00 a six pack most likely will not satisfy that expectation. For those not familiar with carbon shaft technology, ask questions from your provider. Ask the pro's and con's of what they are offering. "Pretty" pictures of shafts/arrows is fine, Even prettier pictures are those of multiple arrows stacked up in a target at 100 yards. The right shooter, bow and arrows can do it! YOU can do it! Makes those 40-50 yard shots at an animal a walk in the park!

Good luck to everyone this upcoming season.
Aim Small, Miss Small
FD
 
#6 ·
George, thank you for sharing.
Degradation. What %age do you contribute to shooting and to age? Also, best storage recommendation for completed arrows.
Hi Steve,
Not sure I understand your % age question. If you are referring to plain fiber shafts?, I have experienced some that experience the start degradation in 25 shots when used with a "No Speed Limit" target at around 400 FPS. The more you shoot the more the POI opens up. Making one to think something in the bow is beginning to cause it when it is the shaft breaking down in column strength and or spine.
As far as storage, Woven shafts are somewhat hygroscopic due to some of the fibers being exposed after OD grinding. Plain fiber not so much. Air conditioned storage is always best however wovens will absorb moisture from the air, being slightly hygroscopic, and actually weigh more than if dead dry. We are splitting hairs here on the difference. I found 3 grains max absorption on 18"woven shafts. I'm not that good of a shooter to see the difference but it is there for reference.
Great questions, as always.
FD
Sorry Steve, my fat fingers must have combined yours and my text....
FD
 
#4 ·
F D thank you sharing definitely a plethora of different needs out there to be met. To many times we get hung up on our own style of shooting/ hunting needs. And forget there’s many different ways to skin a cat to successfully accommodate the needs of the person doing the skinning. This information is very helpful to folks & I’m sure can and will help many individuals in selecting the proper arrows for their individual needs.
 
#5 ·
This is the reasons I don’t have a website that way I can Taylor the build to the bow broadhead and each persons wants and needs on each set of arrows. Not all bows need the same thing. This is also the reason I buy so many bows to see for sure what each one needs. Most do not do this..
 
#7 ·
I would agree somewhat but not in totality. I think we could all agree that the "arrow" is a projectile that IF built correctly will penetrate the air the same every time when launched by a given force. If the tangent of the induced force changes then so will the projectile. If the arrow has the appropriate fight parameters then and only then would the force applied alter the angle of launch of that same arrow.

My testing has proven beyond my shadow of a doubt that the NOCK design has a much greater influence in a bow or arrow performance. My recent, well defined testing, took one dozen arrows that shot 1.5" groups at 100 yards with brand % nocks. Removed those nocks and installed brand # nocks in the same arrows, same atmoshperic conditions, that provided a disappointing 8" group. If arrows are built with different nocks due to manufactures warranty demand or by bow design or by consumer requests then one should expect one well built arrow to fly differently based on the nock design. That being said, why are so many "nocks" being changed/tested in flame throwers to find some provide better performance?

I may have missed your information on what nock you recently discovered that seems to work best out of the 515. I thought you stated that the same arrows shot tight with these new nocks verses the original. Yes/No?

This is all valuable information for all members to learn from hard work and dedication to the sport.
FD