Page 18 - Des Pawson "Pocket Guide to Knots & Splices"
P. 18
Equipment
Over the centuries mankind has made direction of the twist as seen in the
rope from many materials, both plant yarn, strand, or rope. This avoids the
fibers and animal fibers. These may be question as to what is meant by left and
twisted or plaited together. In the past right, which could refer to the direction
this would have been done by hand or shown in the twist or the direction in
with very primitive machines. Today, which the twist is applied.
many new synthetic materials have Much of the rope used today, espe¬
been developed, far stronger than the cially that using fiber from synthetic
natural fibers, and machines have been materials, is braided. Sometimes it is
built that can make thousands of feet braided as a hollow tube, sometimes
of rope in a day. with a core which may consist of yarns
Twisted rope is made by twisting of the same or different material braided,
(or spinning) together fibers in one twisted, or left parallel. There are also
direction to make yarn, then a number braids made from eight or twelve
of yarns are twisted (or to use the rope¬ heavy strands, half the strands being
making term “laid up”) together in the S-laid and the other Z. This gives a
opposite direction to make a strand. rope that does not easily kink and
Three or four of these strands are then makes an ideal anchor rope.
usually laid together with an opposite Cordage is the collective word for
Pocket Guide to Knots & Splices
twist to make the rope. Occasionally all types and sizes of rope, and there is
three ropes may be twisted together a great choice of fibers that cordage can
again in the opposite direction to make be made from. Each of the fibers has its
what is called “cable laid rope,” usually own properties and may be just right
referred to as “cable.” for a certain job. There are two main
There can be much confusion as to groups of fibers: those made from
the description of the direction of the natural materials derived directly from
twist of any one of the components. plants and synthetic or man-made
The industry standard is to define it by fibers that are chemically created,
the letters S and Z, the body of the being extruded from machines as
appropriate letter signifying the continuous fibers.
16
