Whipping knot
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A whipping knot or whipping is a binding of twine around the end of a rope to prevent the fibres of the rope from unravelling.
When a rope is cut, there is a natural tendency for the cut end to fray. A whipping is one way to try to prevent this, by applying multiple turns of twine (sometimes called small stuff) tightly around the rope very near the cut end. The whipping can be made neat and permanent by tying it off or sewing the ends of the twine through the rope.
When doing this to thick sailing-ship-type rope, the "small stuff" used was sometimes whipcord, whence the word usage.
Whipping is suitable for synthetic and natural ropes and lines. It is suitable for both stranded and braided ropes, lines and cables (3-strand rope, 4-strand cable and 8-strand multiplait as well as concentric and braided constructions).
Whipping takes time and some skill to apply, and may need specialist equipment (palm, needle etc). It provides a neat, soft, aesthetic, and permanent ending to the rope.
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[edit] Types of whipping knots
[edit] Alternatives to whipping
[edit] Constrictor knot
A constrictor knot or a turn of self-adhesive plastic tape can be used temporarily to hold the fibres of a cut line until a final whipping can be applied.
[edit] Melting
The ends of some man-made fibers such as Dacron, Nylon, polyethylene, polyester, or polypropylene may be melted to fuse the fibers together and prevent their ends from fraying. This may be done by cutting through the rope with an electrically heated rope cutter, or cutting with a knife and melting the ends in a flame. The cool (transparent) part of a butane lighter flame is best for this.
Although quick to apply and taking no great skill to learn, melting has a number of disadvantages. Many believe that melting the ends is most appropriate for finishing small-stuff, but is not recommended for working ropes and lines. Melting the fibers is a relatively poor method of finishing a rope's end, and the end of any rope subject to heavy use should be whipped as well. Melting cannot be done on wet rope and is often untidy when done on used or dirty rope. The melted end will be hard and can cause injury for example if flicked in the face. With age, use and ultraviolet damage, the hard end will crack and the sharp edges so produced can cut the hands in use, especially if the end runs through the palms. The melting process can easily be overheated causing an unsightly, rough, blackened end, especially if a hot flame is used. Melting is difficult to do outdoors in any breeze and, if the rope is overheated or catches fire, can produce toxic fumes in an enclosed space. There is a fire or injury risk on a boat, especially if the fibres catch fire and molten or burning plastic begins to drip.
Melting cannot be used on natural fibre ropes and lines, or on some types of synthetic lines. Natural fibers like manila, sisal, cotton and hemp will burn instead of melt. Aramid fiber such as Kevlar cannot be melted - the fibers merely char. Such rope must be finished with an appropriate whipping - ideally one completed with a needle such as a Sailmaker's whipping although a West country whipping also serves well.
[edit] Back splice
Whipping is not to be confused with splicing, which uses the rope's own fibres. Splicing can be used to end a rope, to join two ropes together, or to join one rope to itself to form an eye or loop.
A back splice can be applied to the end of any rope, especially stranded ropes. It is most suitable for bucket ropes and other lanyards.
A back splice adds extra thickness to the end of the rope, so that it will no longer pull through blocks and sheaves. The extra thickness may however be seen as an advantage as it allows the user to feel the end of the rope coming into the hand, for example on a bucket lanyard when fetching water from a river bank or from the deck of a boat.
To be truly robust and permanent, the ends of the strands may still need whipping, or the whole splice serving after the back-splice is finished as this work will not be held in permanent tension, and may tend to unravel if banged around in use.
Splicing takes time and skill to apply, and may need special equipment (fid and small-stuff or self-adhesive tape) while working.
[edit] Liquid whipping
Another modern alternative is "liquid whipping". This is a commercial, glue-like product that is used by dipping the end of the rope into the liquid. When it sets, the product is flexible but solid enough to keep the rope together. Liquid whipping can be used on both natural and synthetic fibers.
[edit] Aglet
An aglet is a permanent ending applied mechanically to bind the end of the rope. A typical example is the plastic aglet at the end of a shoelace. Metal aglets may be crimped onto ropes or cables. Aglets may also be made by melting a softer metal to cap the end of the cable.
