Chain
Most serious cruisers prefer an all-chain
anchor rode. There are a number of reasons
for this:
1 .The chain doesn’t chafe or abrade on
rock, coral, or other underwater
hazards.
2 .The weight of the chain creates a sag
(a catenary curve) that absorbs shock
when surges lift and straighten it. (The
word chaincan be traced back to the
Latin word catenafor “chain” or
“brace,” and catenais the root for the
catenary curvea chain makes due to
its weight.)
3 .With a proper windlass and anchor
locker, the entire rode and chain self-
stow and self-deploy reliably.
4 .The weight of the chain increases
anchor holding power by lowering the
angle of pull to be more nearly
horizontal.
Drawbacks to chain include the following:
1 .It is much heavier than rope.
2 .It is more expensive than rope.
3 .Except in short lengths and small sizes,
chain can’t be managed by hand and
requires a windlass, which adds more
weight and more expense.
4 .Though chain has the catenary sag to
help absorb shocks, once the catenary
has been straightened out under load
(e.g., in a sustained strong wind) there
is no elasticity left to absorb shock.
Rope has great elasticity or stretch to
absorb shock.
Because rope can chafe (particularly
along the seabed) and because the weight of
a length of the chain improves the angle the
rode pulls on the anchor (makes the load
direction more nearly horizontal), even so-
called all-rope rodes require some length of
chain at the anchor—a chain leader:
- For small or lightweight dayboats, use
one fathom (6 ft., or 2 m) of chain leader
from the anchor to the rope.
- For all other boats, use a chain leader at
the anchor at least equal to the LOA of the
boat. (For performance boats, where the
ultimate in weight saving is required,
half of LOA can be used, though this
results in some reduction in anchor hold-
ing power and some increased risk of
chafe damage to the rope rode.)
There are many types of chain, and it’s im-
portant to spec the correct type as well as size.
Stud-Link Chain
Ships use stud-link chain (Figure 23-1). The
studs (crossbars between each link) make the
chain both stronger and heavier. The studs
also somewhat reduce the tendency of chain
CHAPTER 23 Anchor Rode
