Page 33 - Randy Penn Everything Knots Book

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THE EVER YTHING KNOTS BOOK

you can distinguish between a natural and a synthetic rope, but
that’s not always the case. Synthetic ropes come in a wide variety
of textures and colors, many of which mimic natural fiber ropes.

ESSENTIAL

Some activities require rope to meet very precise standards.
For pursuits such as mountain climbing or rigging a sailboat,
the cordage should meet with specific guidelines to ensure
safety. To find out whether a particular type of rope fits the
requirement, contact the rope manufacturer.

Nylon Cordage
The term nylon, like most terms for synthetic materials, actually
refers to more than one formula or specific material of similar prop-
erties. Nylon cordage is used in cordage of all sizes from large
mooring cables to fishing line and thread. It is somewhat elastic,
and hence can absorb more energy from shock loading (tempo-
rary tension when the rope comes under sudden strain) than other
materials. It is one of the stronger synthetics, sinks in water, and
is slightly weaker when wet.

Polyester Cordage
Polyester, also known as Terylene and Dacron, is similar to
nylon because it’s nearly as strong, but it has much less stretch. It
has better resistance to acids and sunlight, and also sinks in water.
Polyester ropes are often used in boating and other applications
where little stretch and less resistance to shock loading are required.

Polypropylene and Polyethylene Cordage
Polypropylene and polyethylene both float in water, and
polypropylene is a favored material for water rescue and water ski
ropes. They are both weaker than nylon or polyester, but still

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