There are very few ropes today that are still manufactured from natural fibres such as manila, cotton, sisal and coir. In the small boat industry, most ropes are synthetic. Examples of synthetic ropes are nylon, polypropylene, polyester, and polyethylene.
Nylon is the strongest and it is very durable both when wet or dry. It also has great elasticity, although there is an inherent danger in that if it parts when under tension, the ends may whiplash. (With a rope of large diameter, such a whiplash can have a devastating effect). Another drawback is that nylon becomes slippery when wet. Polypropylene is the most commonly used of the synthetic ropes because it floats and has low stretch, and its coarse texture means that it’s not slippery when wet. Polyester, which is also known as yacht rope, is soft and firm to grip. It has very good resistance to abrasion and has low stretch. Polyethylene rope has a waxy feel and it becomes slippery when wet.
All synthetic ropes suffer from ultra-violet deterioration, although polyester has the highest level of resistance to UV damage. Synthetic ropes, however, do not suffer from rot, mildew and fungus, at all – except for nylon– float. The strength of a rope where it has been spliced has a loss of 12% and where it has been knotted, a loss of 50%
How to prolong the life of your boat’s ropes
• Never overload. The safe working load is 16% of a rope’s breaking capacity.
• Keep the rope clean and free from oil, petrol, sand and mud.
• Guard against chafe, abrasion and accidental knots.
• Do not place a rope under tension while it has a kink in it.
• For natural fibre ropes: lash the ends to prevent fraying. For synthetic fibre ropes, hold the end over a low heat to melt the fibres together, thereby preventing the rope from fraying.
• Do not expose to sunlight when not in use (this point is only applicable to synthetic ropes).
Some types of knots you will commonly use:
• The clove hitch is used for hitching fenders to a rail, or for mooring a boat temporarily to a ring or spar. It can be tied quickly and is easy to untie.
• The fisherman’s bend is a self-jamming, permanent knot and is ideal for securing rope to the anchor chain.
• The bowline is used for making a non-slip eye or loop on the end of a rope. It’s the most useful knot out of the group but it can’t be untied under load.
• The figure of eight knot is a stopper knot used to prevent the end of a rope running through any eye or block. It also prevents the end of a rope from fraying. This knot is easy to untie, even when wet or under load.
• The reef knot is for joining two ropes of equal diameter. It is safe when under constant tension and is most commonly used when securing a reefed sail, hence the name. …