The choice of a rope primarily depends on what you plan to use it for and how much money you are willing to spend. For example, you should not give a climber a beautiful and expensive rope made of zylon so that he breaks his back, falling off a cliff because the rope does not stretch. But nylon may well suit him, because it stretches and dampens the inevitable shock loads when dropped.
And vice versa, the owner of the yacht will like donated fastenings for sails, but not from stretching nylon, because he will have to constantly tie them up so that the sail is pulled properly. Polyester cord is much more suitable here..
Rope selection, purpose, structure and tensile strength, nylon, polypropylene, polyester, daima, spectra, vectran and zylon ropes, folding and storing the rope.
To decide what type of rope you need, consider the following points:
Should she reach out?
Do you need a floating rope?
Is friction resistance important??
Will the rope often be exposed to ultraviolet light?
Are you ready to buy a cheap and therefore disposable rope?
Are ropes specially designed for what you need?
Is rope color important to you??
Purpose of nylon, polypropylene and polyester ropes.
As a rule, modern rope, both mountaineering and sea, are woven, with a smooth whole surface, unlike older twisted or twisted ropes made of plant fibers. Rigid twisted cables exist now and are used a lot where, but still they are not as popular as before.
Some synthetic materials deteriorate from excess ultraviolet radiation. In order for their service life to be sufficiently long, it is necessary to use inhibitors. Some modern materials, such as Kevlar and Vectran, are so sensitive to ultraviolet that they must be stored in complete darkness until they are woven into a rope that protects them from light.
Breaking strength of the rope.
There are various tables of tensile strength indicators that help you choose a rope of suitable diameter for a specific task. It’s better to use the latest data, because manufacturers are constantly changing indicators.
However, in most cases, the strength of the rope can be ignored. It is enough to choose the thickness with which it is convenient to work in each specific case. For example, the rigging of a family yacht should be about 12 mm in diameter so that it is easy to handle, but the strength of ropes of this diameter far exceeds the maximum rigging load. If the strength is still critical, as for fishing line, the maximum load is indicated at the time of sale. For example, a fishing line of 9 kg or 20 kg.
Rope diameter and tensile strength by type of rope.
Nylon ropes, material features.
This is the first synthetic material that was used to make cords and ropes. Nylon is a durable stretch material. Climbers are especially fond of it, because it dampens shock loads well. For example, if someone breaks off a cliff.
However, surprisingly, the strength of nylon is greatly reduced when it gets wet. Decrease can reach 20%. Despite this, nylon remains one of the most popular durable materials. It is also used as monofilament for fishing line, which, due to its strength, can be very thin.
Polypropylene ropes, material features.
Polypropylene is multifunctional. It is used mainly in the form of a twisted rope of three threads. There are five main types and is quite cheap. Ropes made of polypropylene are held on the surface of the water, are used for a variety of purposes, but deteriorate from friction and ultraviolet radiation.
Polypropylene monofilament is the most resistant to friction and general fatigue. It has a slippery, dull coating, hard to the touch, which is not very convenient to tackle. Polypropylene fibrillated (film) thread is very cheap. If its ends after cutting are not immediately sealed or fixed, it will quickly unravel.
Polypropylene twisted fiber is coarse and fleecy. Reliable, but keeping it is not very convenient. Filament propylene forms a soft and easy-to-use thread that holds the knots better than a more elastic rope.
Brown fibrillated polypropylene, similar to a natural hemp rope. It is also cheap and attractive, but uncomfortable in hands, so now it is almost replaced by twisted polyester, which is softer and more convenient for use in traditional navigation.
Polyester ropes, material features.
Ropes and cables made of polyester are both woven and twisted three-row. They have almost the same maximum load as nylon cables, but they stretch less, especially before the preliminary stretching. Polyester cables drown in water and are resistant to abrasion.
Ropes made of exotic materials.
In addition to traditional materials, the rope is made from exotic modern materials, for example, dima, spectra, wectran and zylon. The latter is five times stronger than polyester, almost does not stretch, but costs 35 times more expensive. This is a very specialized material..
Folding and storing the rope.
When ropes and cables are not used, they must be folded and stored carefully so that they can be used quickly if necessary, without wasting time unraveling and disassembling.
The thrown rope will be confused, interfere with people and may suffer. Therefore, each time fold and remove the rope, and when it is loose, make sure that it does not get confused. Always twist the three-strand rope in circles clockwise, and braided by eights.
Overlapping is the easiest way to store a three-strand rope. Roll it up, make the free end half loop around the skein. If the rope is rigid or elastic, the half-loop will not be reliable enough, unless you then hang the rope at the end going from the knot.
(a) Gently wind the rope in a clockwise direction..
(b) Fold the remainder on top into a smaller ring.
(c) Pull the end of the rope over the skein and then underneath it towards you so that it passes through the small ring. Now the rope can be suspended by the free end.
Self-tightening coil of rope.
There are two more ways to fold storage ropes. Both of them allow you to neatly and safely store the rope. In the first case, the rope can be suspended by the free end, in the second by the loop.
Based on materials from the book Big Book of Knots.