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line's performance is proportional to its inherent characteristics
of strength, stretch, handling and chafe/abrasion resistance.
The desired attributes for a given application are achieved
by combining the proper fiber or fibers with the appropriate
construction technique. Today we use fibers such as nylon, polyester,
Technora, Spectra, and Vectran in combination with a laid (twisted),
braided, or parallel core construction to perform the varied
functions required by yachtsmen. Before selecting a line, it
is important to know how to recognize quality when comparing
products; it can be difficult to distinguish the quality or
type of fiber used. However, an examination of the finished
product's construction can help predict performance. |
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BRAIDED
ROPES

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When selecting braided ropes, look for these characteristics:
- Rope
should be firm enough to resist chafe, snagging and wear
but flexible for easy handling and splicing.
- The
yarns and strands should lay smoothly and uniformly in the
rope so they will work together and wear evenly. Unevenness
can be detected by sighting down the rope. If it appears
wavy or uneven, don't buy it.
- The
amount of direction of twist in the yarns is essential for
top performance in a braid. Look at the individual yarns
that make up each strand. Well rounded yarns resist snagging
and wear better than flat yarns.
- Most
braids have an inner core with an outer jacket. As the line
is used and flexed, the core may tend to work its way thorough
the outer jacket resulting in a "hernia." Grip
the rope with your thumbs facing one another about 2"
apart and violently flex the section between your thumbs
a dozen or more times. If the jacket opens and exposes the
core, it is approaching herniation.
- The
inner core should lay evenly in the jacket. Lightly grip
the rope and run it through your hands. You don't want it
if it is "lumpy", or soft. The rope should feel
firm and round.
- The
rope should be heat stabilized to precondition it and keep
shrinking and hardening to a minimum.
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THREE
STRAND ROPE

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When
selecting 3-strand rope look for the following characteristics:
- Rope
should be firm but flexible. A firm rope resists chafe,
snagging and wear, and also prevents hockling or kinking.
Test the rope by flexing it a bit. It should require effort
to open the lay of the rope for inserting the first tuck
of a splice. The effort is light for a small size such as
1/4" and great for 5/8" or 3/4". If it opens
easily, it's too soft, and will not last.
- The
3-strands should lay smoothly and uniformly within the rope
so they all work together and wear evenly. Sight down a
length. If it appears slightly "wavy" and uneven,
there is a high or low strand and the rope is "out
of lay." Don't buy it.
- Nylon
and Polyester (Dacron) fibers are very fine (smaller than
a human air) and, therefore, fragile. Consequently, they
should be laid into a rope with sufficient twist in the
yarns and strands to form a round, firm, balanced structure
that resists snagging and wear. Push your thumbnail into
the strand. It should not be soft and punky.
- The
rope should be heat stabilized to precondition the rope
and keep shrinking and hardening to a minimum.
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FIBER
CHARACTERISTICS
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| NYLON |
- Most
elastic of all fibers.
- High
stretch and strength.
- Minimal
strength loss when exposed to sunlight.
- Ideal
for use where stretch and energy absorption are important,
such as in dock-and-anchor lines.
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| POLYESTER |
- Low
stretch fiber.
- Very
good abrasion resistance wet or dry.
- Excellent
weathering characteristics.
- Spun
Polyester is fuzzy. Filament Polyester is smooth.
- Good
choice for running rigging requiring moderate to low stretch,
good durability and a nice feel.
- Often
referred to as Dacron, a DuPont trade name.
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| POLYPROPYLENE |
- Light
weight and minimal stretch.
- Floats.
- Very
susceptible to UV degradation.
- Melts
under high friction
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| TECHNORA |
- Highest
strength aramid fiber.
- Very
low stretch.
- Subject
to fatigue if cycled over small radius.
- Does
not creep under normal loads.
- Black
version has superior resistance to UV degradation.
- Ideal
for low stretch running rigging, such as halyards.
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| SPECTRA |
- Very
high strength and very low stretch.
- Light
weight; will not absorb water.
- Low
melting point. Susceptible to friction.
- Very
slippery.
- "Creeps"
- gets longer under sustained load.
- Ideal
for low stretch running rigging requiring light weight.
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| VECTRAN |
- Liquid
Crystal Polymer fiber.
- Very
high strength.
- Extremely
low stretch.
- Zero
creep.
- Low
water absorption.
- Good
resistance to "Flex Fatigue".
- Ideal
for low stretch running rigging on competitive race boats
and mega-yachts.
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A
NOTE ABOUT STA-SET T-900
Technora
and Spectra are high-tech fibers whose characteristics of very
high strength and very low stretch makes them ideal for running
rigging. New England Ropes has made ropes with 100 percent Spectra
or 100 percent Technora cores, but recognizes that each has
its shortcomings. Careful blending of these fibers yields improved
performance. The super slippery Spectra lubricates Technora
fibers for longer service life. Technora prevents creep and
core slippage associated with Spectra. Special processing techniques
control the fiber distribution and tension during and after
the blending process. The result is the best performing yachting
rope available. |
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