Page 10 - Mario Bigon "The Morrow Guide to Knots"
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covering, while the strength of the rope lies solely in its
internal part which is also braided and is known as the core
(d). Both types of rope have their own special characteristics
which make them better suited to certain applications; twisted
rope is less flexible and better for heavy-duty work, whereas
braided rope is a lot softer and if pre-stretched does not
expand any further. Rope should be bought with a view to
choosing the most suitable type for the job you have in mind.
materials
The characteristics of a rope obviously depend to a great
extent on the fibers that make it up, so it is useful to know what
the characteristics of the different materials are. From this you
can deduce those of the corresponding rope.
The names of the materials may be somewhat confused as
chemical names like polyester are freely mixed with the
manufacturer's brand names such as Tergal. Dacron, etc. The
following list gives only the chemical classifications and the
table on page 14 gives the most common brand names for the
equivalent products. It should also be noted that manufactur-
ing companies now offer many variants of the same product
(with greater or less strength, elasticity etc.). The following
data refer to average characteristics.
a. fiber b. yarn c. strand d. core e. sheath
1 and 2. twisted rope 3. braided rope
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