Some breaking loads

Material

Diameter

lin =

25.4mm

6mm

8mm

10mm

a ramid core

2640

5510

8460

nylon, 3-strand

1650

2980

4590

polyester, 3-strand

1250

2250

3500

polyester, 16-braid

2200

3750

5730

polypropylene, 3-strand

1100

2000

3000

polythene, 3-strand

8 B0

1540

When you buy synthetic rope from a chandlery, an electrically heated knife is used to cut the rope to the required length This gives a sharp edge and seals the end. When you cut synthetic rope yourself, however, you will probably use an ordinary sharp knife and then melt the end of the rope with a cigarette lighter or an electric ring.

Looking after rope

Rope is expensive so always look after it. Try to avoid dragging it over sharp or rough edges, or over surfaces where particles of dirt and grit will penetrate the fibers. Do not force rope into harsh kinks. Use floating lines only for rescue work, light buoys, etc.

Before coiling it, always make sure that the rope is dry, even it it is synthetic. If it has been in sea water, rinse it with fresh water to remove any deposits of salt. At the end of the season, wash ropes thoroughly in a detergent, carefully removing any oil or tar stains with petrol or trichloroethylene.

Tying knots weakens ropes. The sharper the curve and the tighter the nip, the greater is the chance that the rope will break, and when it does so it will break immediately outside the knot. Many often-used knots are surprisingly harmful to rope, the worst offender being the simple overhand knot (see page 12). Never use two ropes of different materials together because only the more rigid of the two will work under strain.

The function of coiling is that the rope will be immediately accessible and untangled when needed. Coiled rope is useful if you want to sling the rope on your backpack or over your shoulder.

COILING A ROPE

Selecting knots

One of the main reasons for selecting one knot rather than another is the relative strength of the knots. This is especially true for climbers and mountaineers, but it is also a consideration for mariners. Other characteristics such as speed and ease of tying, bulk and reliability will also influence the choice.

Climbers generally use knots that are bulky and that have several wrapping turns, which are designed to absorb strains and to avoid weakening the rope unnecessarily. Knots used by climbers must be checked regularly, especially if stiff rope is used, because it is more difficult to tie than more flexible line and the knots may be less secure.

Anglers use similar, but much smaller, barrel-shaped knots, partly to improve their chances of a good catch and partly to safeguard expensive fishing gear.

Generally, you should also untie knots as soon as possible after use. This will be easier if you choose a suitable knot in the first place. And remember that knots that disappear when they are slipped off their foundations such as the clove hitch and Prusik knot (see pages 24 and 34) are no less strong or secure.

Finally, remember that tying knots requires practise. You must be able to tie them quickly and easily when you are halfway up a mountain or at sea. The only way to gain the necessary skill and confidence is to practise each knot over and over again until the steps become automatic and you do not have to think about them. In some circumstances your life or the lives of your companions could depend on it.

ROPE PARTS

ROPE PARTS

MOW TO USE THIS BOOK

The diagrams that

completely different knot

GENERAL PURPOSE

accompany the

The knots in this book can

descriptions of the knots

be used in different

are intended to be self-

situations: general

--

explanatory. The arrows

purpose, climbing,

C A M P I H G

indicate the directions in

camping, sailing and

which you should push or

fishing; these are shown

pull the working ends of

below as symbols.

C1IMBINC

vourline, white the

Each knot in the book is

to

doited lines indicate

accompanied by Ihe

Wm

intermediate positions of

relevant sy m bo l/s;

A

the rope. Always follow

designed to give you at-a-

A

SAIIINS

the order indicated of

glance information about

going over or under a

the uses of a particular

length of line; reversing

knot.

—if:

this order could result in a

m

OVERHAND LOOP

OVERHAND LOOP

MULTIPLE OVERHAND KNOT

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