Fiber Orientation

A material's contribution to a structure is determined by its inherent strength and its resistance to being dislodged from its intended position. Regardless of how enormous the inherent strength of a material, it cannot contribute unless it is secured well.

Fiberglass is very strong, with a tensile strength of somewhere between 20,000 and 40,000psi, depending on construction. In Epoxy boards, it is held in place by the Epoxy resin with a tensile strength of about 2000psi. That is only about 1/10th the strength of the fiberglass! We need to make sure, then, that as the composite is stressed, the fiberglass takes the load, and not the weaker resin. The only way this is going to happen is if the fibers are aligned in the direction of the load, and are straight. If the fibers run in a wiggely manner, the resin will have to fail in order for the fibers to straighten and take a load.

Observe this length of 1/2" Spectra yacht braid, with a breaking strength of 17,000#.

That is its potential strength.

Lying there all wiggely, I can pull with 1/2oz of force and disturb it. All its potential strength is going to waste.

Now the line is straight, and try as I might, the only thing I could disturb is the post the line is tied to (because I eat right, and because the termites have been in that post for a few years now)

marketed as "advanced CarbonTech", very helpful, eh?

this didn't work so good, either

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