Page 23 - Des Pawson "Pocket Guide to Knots & Splices"
P. 23
Pocket Guide to Knots & Splices
chopped up and then spun, giving a ance on the market they are:
hairy rope, has much more grip. Kevlar/Twaron/Technora (aramid),
Splitfilm rope is the most inexpensive Spectra/Dynema (HMP, high modu-
of all the polypropylenes, some ropes lous polyethelenes), Vectran (LCP,
being only fit for one-off, temporary, or liquid crystal polymer), and Zylon
disposable tasks. Some manufacturers (PBO, poly [P-phenylene-3, 6-benzo-
have developed a brown fibrillated bisoxazole]). In the main, they are not
version of the polypropylene fiber that yet for everyday use, although HMP
looks very similar to hemp and has has started to be used in some fishing
been used on some traditional boats lines and kite lines. They are very
for that old-time look. Recently a expensive, and have various draw¬
number of manufacturers have started backs such as their vulnerability to
mixing the polypropylene material light or chafe, so are often covered with
with polyester or polyethylene at the another material, usually polyester.
extrusion stage of fiber production, to Some of these materials do not work
make various copolymer ropes that well on tight curves, which means that
have a much greater strength and chafe knots reduce their strength and so
resistance, yet are not much more special splices or terminals have to be
expensive than the better quality developed. One thing can be certain,
polypropylenes that the scientist will continue to
develop yet more and better rope mak¬
Exotic rope materials have been ing materials, and craftsmen will have
developed over the last few years that to learn how best to use them.
are lighter, stronger and have less Whatever the rope is made from, it
stretch than anything seen so far. They is a valuable commodity and it needs
are being used to replace wire rope looking after, Natural-fiber ropes need
rigging on racing yachts, and in various to be dried out properly if they get wet.
hi-tech industrial uses. All these exotics All ropes need to be kept clean, as
are sold under various trade names or sand, salt, dirt, and oil working their
initials to represent the complicated way into a rope will wear it out from
chemicals from which they are the inside. So, a good wash and scrub
constructed. In order of their appear¬ will extend the life of a rope, using
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