Page 143 - Barbara Merry - The Splicing Handbook

FIFTEEN
Introduction to Wire Rope

“When you have completed as many wire splices as you are old, you will be
ready.”

—PETER KLENK

Lore has it that wire rope was first used in the mines in Germany, where even the
best-crafted plant fiber ropes failed quickly. Wilhelm Albert is credited with the
first official wire rope walk there in 1831. Subsequent history of wire rope is a
bit unclear. I’ve heard that John A. Roebling, a graduate engineer of Berlin,
emigrated from Germany to America with a diagram of Albert’s wire rope walk
in his pocket. Another source indicates that Roebling found an obscure paper on
how to set up and run a wire rope walk, and that by 1841 he had set up a wire
rope walk in Germantown, Pennsylvania.

Before the U.S. Civil War, embers from the fires powering steamships often
drifted aloft, catching fiber riggings on fire, so slowly fiber rigging was replaced
by wire. During the Civil War mariners discovered that steel rigging had the
added benefit of resisting enemy cannon fire, keeping boats intact and afloat
longer than they would have with traditional fiber rigging. After the war, wire
rope found its way onto steel suspension bridges and telegraph wires.

Today wire serves many purposes—from cables holding highway guardrails to
wires supporting the telephone pole outside your window. The aircraft and
logging industries use a great deal of wire, and the boating world does too.
Sailing dinghies use the smallest diameter wire rope to hold their masts aloft,
powerboats use wire steering cables, and large fishing draggers use wire to
connect their immense trawls to their boats.

WIRE CHOICES FOR BOATS

Wire rope is made up of wire strands in groups (twisted) circling a core of soft
fiber or hard steel and is available in galvanized and stainless steel. Wire rope is
used in slings, winch ropes, and guy wires and is also acceptable for shrouds and
stays. The term aircraft cable sometimes refers to wire rope, but indicates that
the wire has been constructed with special strength for the aircraft industry. Wire
rope is often offered with a coating of white plastic for lifelines.

Use is a prime consideration when choosing wire. A steering cable, for
example, should be made of the finest stainless steel available and be as flexible
as possible, because it is in constant motion. Shrouds, on the other hand, should