All About Arrows
ARROW ANATOMY
An arrow is a fin stabilized projectile that is launched from a bow. It consists of several key parts that create a reliable projectile.
Figure: Arrow components and features.
ARROW COMPOSITION
Arrows are made of different materials depending on their application. Each material has pros and cons.
Wood
Composed of 50% Carbon, 42% Oxygen, 6% Hydrogen, 1% Nitrogen and 1% of other materials.
Pros:
- Original arrow material
- Cheap to produce
- Easily made
Cons:
- Durability
- Inconsistent strength and stiffness
- Weak and heavy
Aluminum
Composed of 98% Aluminum, 1% Magnesium, .6% Silicon, .2% Copper and .2% Iron.
Pros:
- Lightweight
- Sturdy
- Versatile
Cons:
- More expensive than wood
- Easily bent
- Poor vibration dampening
Fiberglass
Composed of 53% Silicon, 31% Oxygen, 12% Calcium, 1% Carbon, .5% Sodium and 2.5% other materials.
Pros:
- Durable
- Inexpensive
- Consistent
Cons:
- Heavy
- Slow
- Brittle
Carbon
Composed of 92% Carbon, 3% Hydrogen, 4% Nitrogen, .3% Sulfur and .7% other materials.
Pros:
- Stiff
- Very lightweight
- Durable
- Consistent
Cons:
- Prone to splintering
- Expensive
INTERNAL FORCES
Compression is a force that presses inward on an object causing
it to become compacted.
Tension is a force that pulls outward on an object causing it to become
extended.
Figure: The yellow object is in compression and the blue object is in tension.
BENDING AND DEFLECTION
Bending is the reaction of an object when an external force is applied to it. Deflection measures the actual change in a material subjected to bending. Arrows are rated according to their stiffness, which is the extent the arrow resists deformation in response to an applied force.
Figure: The magnified image describes how the material on one side of the arrow is in compression while the material on the opposite side is in tension when the arrow is bent.
SPINE RATING
The stiffness of an arrow is known as spine rating. Having incorrect arrow spine for a bow results in erratic arrow flight and poor grouping.
Figure: Choosing an arrow with an incompatible spine rating for a given bow can lead to poor accuracy on the target.