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CHAPTER 3
MARLINESPIKE SEAMANSHIP
Marlinespike Seamanship is the art of handling and
working all kinds of fiber and wire rope. It includes
every variety of knotting, splicing, serving, and fancy
work. Although canvas and leather work are not part of
marlinespike seamanship, we will briefly discuss them
in this chapter.
You will find marlinespike seamanship easy to
learn if you master the basic knots before you try the
fancy work.
This chapter is important because you will handle
and work with all kinds of line and wire rope aboard
ship.
For example, you will use line for tying up during
mooring and docking and for rigging aloft or over the
side during painting details. You will also use wire rope
during replenishment of supplies and for highline
transfers. These are only a few of the jobs that require
you to use line or wire rope; there are many more.
Learning the proper care and methods of handling line
and wire rope and practicing these techniques are an
essential part of your job as a Seaman.
ROPE
LEARNING OBJECTIVE: Explain the con-
struction, use, care, and other characteristics
of wire rope and line.
Rope is manufactured from wire, fiber, and
combinations of the two. Fiber rope–or line, as it is
commonly called–is fashioned from natural or synthetic
fibers. Lines made from a variety of natural fibers
(cotton, agave, jute, hemp, sisal, and abaca) have seen
service in the Navy in the past, and some are still used.
For example, tarred hemp is known as marline and
ratline. On the other hand, sisal may still be found as a
wire-rope core. Manila (made from the fibers of the
abaca plant) formerly was authorized for use only
where great strength was required. Now, manila is
authorized for lashings, frapping lines, and steadying
lines. However, synthetic lines have replaced manila in
most applications.
Rope, a general term, can be applied to both fiber
rope and wire rope. In the Navy, sailors refer to fiber
rope as line, whereas they refer to wire rope as rope,
wire rope, or just wire. More clearly defined, a line is a
piece of rope, either fiber or synthetic, that is in use or
has been cut for a specific purpose, such as a lifeline,
heaving line, or leadline.
This chapter discusses the fundamental uses and
care of rope of all kinds. Knots and splicing may be
difficult to understand, so do not hesitate to ask for help
from a more experienced hand.
CONSTRUCTION OF LINE
Line currently used in the Navy may be three-strand
line, braided, or plaited. In three-strand line, fibers are
twisted into yarns or threads, the yarns are twisted in the
opposite direction into strands, and the strands are
twisted in the first direction, making line. Taking the
process further, lines are twisted into cable. Line can
have various numbers of strands, and the direction the
strands are twisted determines the lay of the line. That
is, if the strands are twisted to the right, the line is said
to be right-laid.
Four-strand line is right-laid strands around a center
core. Each strand is aramid fibers laid into parallel yarns
left laid helically around the strand core with a braided
helical of alternating aramid and polyester yarns.
Braided lines have certain advantages over twisted
ropes. They will not kink nor will they flex open to
admit dirt or abrasives. The construction of some
braids, however, makes it impossible to inspect the
inner yarns for damage. The more common braided
lines are hollow braided, stuffer braided, solid braided,
and double braided lines.
Hollow braided lines usually have an even number
of parallel, tapelike groups of small yarns braided into
a hollow, tubelike cord. This type of construction in
cotton formerly was used for signal halyards–a purpose
now served largely by three-strand and double braided
nylon. Other uses are parachute shroud lines and shot
lines for line-throwing guns.
Stuffer braided lines are manufactured in a similar
manner except that the braid is formed around a highly
twisted yarn core, which rounds out and hardens the
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