ONE OF THOSE QUESTIONS that never
seems to be answered satisfactorily is whether you need rope or chain for your
anchor line. That’s because it all
depends. It depends on the kind of boat you have and where you plan to go with
it.
I always classify would-be anchorers
into two groups: those who anchor frequently overnight on coastal or lake
passages, and those who are busy sailing around the world.
For coastal or lake cruisers I’d advise
an anchor rode consisting of a section of chain as long as the boat, connected
to a main anchor line of a few hundred feet of three-strand nylon. For world cruisers, I’d advise an all-chain
rode. Both rodes need chain right next to the anchor because it won’t be
scuffed or cut by dragging along the sea bed as the boat ranges around in wind
shifts.
The interesting thing about nylon is
how much it can stretch without losing too much strength. This elasticity is a
great help when the anchorage gets choppy, and your boat starts to snatch at
its cable when the bows rise to waves. As the nylon stretches, it takes the
jerk out of the sudden snatch, and then gently eases back to its normal
length. It can do this over and over again
without getting tired.
Galvanized steel chain also can
prevent your cleats from being jerked out by the sudden strains. It does so by
forming itself into a downward curve. It’s
the weight of the chain that forms the curve, and as the boat lurches backward
with a wave, it pulls against the weight in an attempt to stretch the chain bar-taut.
It’s very difficult to make a heavy chain that taut, and the closer it gets to
that stage the harder it becomes, so there is a sort of progressive braking
until the maximum strain has passed, after which the weight of the chain will
form it into a catenary again, ready to absorb the force of the next wave.
In shallow water there might not be
sufficient depth for a reasonable catenary to form, in which case it’s
advisable to attach a suitable length of nylon line to the anchor chain,
forward of the bow, and take up the strain on that.
In deeper water and very high winds,
you can help prevent jerking on an all-chain anchor cable by sending a heavy
weight out forward to help form a deeper curve.
Nylon is lighter than chain, length
for length, and this might be a deciding factor for racing boats, although
chain usually is able to stow itself in a much smaller and tidier package. But I regard all-chain as essential for round-the-worlders
because they so often have to anchor near coral, which would saw through a
nylon rode in no time.
There are also times in crowded
anchorages when dull-headed operators of dinghies with outboard motors frequently
cut too close across your bows, unaware of how close their propellers come to
your anchor line. It’s very nice then to know that you have a chain rode. If
they make contact, it’s their propellers that will suffer. Serves them right.
Today’s
Thought
In
the stormy night it is well that anchors twain be let down from the swift ship.
— Pindar, Olympian Odes
Tailpiece
Income
tax is the fine you pay for reckless thriving.
(Drop by every Monday, Wednesday, Friday for a new Mainly about Boats column.)
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