Page 47 - The Complete Rigger’s Apprentice

Characteristics: Mooring, Dock, and Anchor Lines

Selecting mooring, dock, and anchor lines is quite seem like compelling qualities, particularly consider-
different than it is for sail-control lines: There are ing its cost, but it is hard to talk people out of using it
fewer constructions to choose from, and only one for mooring or anchor lines.
material—nylon—in general use. This is because the Regardless of which construction of line you
job requirements are simpler, involving only adequate select, it is a good idea to incorporate a snubber into
strength and adequate stretch. anchor lines. I like to use Dacron, as it is far more
As the chart below shows, three-strand has the chafe-resistant than nylon (see End-of Bowsprit
advantage of being the cheapest. Anchoring, page 92).
A single-braid rope, such as New England Rope’s Another nice option for mooring lines: end-to-end
Mega-Braid, has the advantage of being more flexible splice a short length of Dacron braid to the inboard
than three-strand, especially in the long run. This end of each mooring line. The Dacron section goes
could be a deciding factor if you have to stuff the to the cleat or bitts, and is just long enough to reach
rope into a tiny stowage locker, or if ease of handling from the belay to well outboard of the chock or
is an issue. As it happens, storage lockers are gener- hawsehole. By far the greatest chafe point is where
ally tiny, and ease of handling is a fundamental virtue the line exits the boat.
for rope. Other than that, the big appeal of single One could also join the sections with two eye-
braid is appearance—it looks so sleek that many splices, but these are more liable to hang up on
people buy it on that basis alone. And this is not a fixtures while you’re handling the lines. Bear in
bad thing; why have an anchor line you can’t stand mind that end-end splice is only 80 percent or so of
the sight of? This appearance appeal is even true for the line’s strength. So oversize the line accordingly,
double-braid nylon. The chart gives it lowest marks or look for a rope manufacturer’s instruction pam-
for performance, but it handles well, and is stronger phlet showing the more involved 100 percent end-
for its size than the other constructions. These hardly end splice.

double-braid nylon
single-braid nylon $

less expensive more expensive
3-strand nylon

stretch at 15% 16.5% stretch 10% 6.5%
of break
weaker for its size stronger for its size

KEY No shading = Most durable
Height = Expense Performance and cost numbers based on lines
Width = Performance (elasticity) of approximately equal strength, not size.
Distance to right = Strength per diameter
Curviness = Handling (more curvaceous, better han- On this chart, mooring line “durability” means resis-
dling) tance to chafe. In the world, UV is a strong degrader
Dark shading = Least durable of nylon, as well as other rope materials.
Light shading = More durable

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