Thread: rigging wire
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Edgar Edgar is offline
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First recorded activity by BoatBanter: Jul 2006
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Default rigging wire


"Richard Casady" wrote in message
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On Tue, 10 Feb 2009 21:55:47 -0500, hpeer wrote:

OK, while we are at it lets clarify what we are talking about when we
say "Galvanized Wire." Most (all?) of it is 7-strand. It comes in a
variety of dimensions and grades. It is important to understand that
not all "galvanized" wire is the same.


I checked out a cable company website. They have wire rope, galv, and
stainless. No seven strand,they had7x7 and 7x19, and maybe 19x7.
Roebling the guy who built the Brooklyn bridge, invented cable with
three sizes of wire, to have less wasted air space, and be rounder.
They sell it today.


The first figure (7) is the number of strands. 7 strand wire is six strands
wound round a seventh wire core.
The second number is the number of individual wires in each strand. In 7 x 7
each individual strand is itself six wires wound round a seventh as core.
Some galvanised wires are 6 x (number of wires). This construction is 6
strands wound round a hemp core.
The higher the number of wires in a strand the more flexible the complete
rope is

So 7 x 7 would be a stiffish wire suited to standing rigging. Not so good
for going round pulleys as the individual wires will be thicker and subject
to fatigue..
Having said that however this wire construction is recommended by the makers
of my steering gear which is why I am now having to replace the wires
because the first strand or two have fatigued and are protruding where the
wire goes round the pulleys at the bottom of the pedestal. However I do not
know how many years thee wires have been in service. If using this wire to
go round a pulley make sure the pulley is as large diameter as possible.

7 x 19 would be more flexible for running gear and because the individual
strands are thinner this wire would corrode more rapidly.

Never heard of 19 x 7. If it exists it must be for some special application,
not for boats.

Standing rigging these days is normally 1 x 19 SS wire. This is a single
strand containing 19 wires and cannot be used where any flexibility is
required