What a sailor expects from a rope anchor rode is not very complicated.
The rode should have great strength, stretch liberally, stoutly resist abrasion, be easy to handle, kink rarely and hockle never.
Although other newer kinds of man-made fibers might satisfy some of the requirements, the stretch requirement dictates the use of one of the oldest kinds of thermoplastic material.
Its name: Nylon.
This highly refined synthetic polyamide-very tough, very strong, very stretchy-comes in sheets, bristles, filaments and fibers. Its the filament version we find so useful in making nylon line. In any form, nylon resists abrasion, ignores chemicals, is low in moisture absorbency, cares little about how its stored and doesn’t get upset about mildew.
Just the ticket for an anchor rode-and much cheaper than an all-chain rode.
In last Decembers Double Issue, we reported on 33 varieties of less stretchy synthetic line, the kind to use for halyards and sheets. Included was another old reliable called polyester (which has many trade names-among them Dacron, Terylene, Tergal, Teteron, Kodel, Duron, Fortrel, etc.), as well as polyethylenes (known as Spectra or Dyneema), liquid crystal polymers (Vectran and Certran), a new one called Technora and various blends incorporating olefin and polypropylene to make them lighter.
Now its nylons turn to be subjected to the Practical Sailor abrasion machine. For those not already familiar with the machine (see photo at the bottom of this page), it is a 3 rpm device to draw a sample rope over a sharp, stainless steel scraper under a 5-pound load imposed by shock cord. The loss of fiber is measured as a percentage of the original cross section. (Getting a measurable amount of loss is determined by initial experimentation; in this case, 360 passes across the scraper were sufficient.)
Along with data on the chart on pages 10-11, the abrasion characteristics should be helpful in selecting an anchor rode.
17 Kinds of Nylon Line
For the tests, 18 kinds of nylon line from seven manufacturers were assembled. Laid and braid, standard and premium, we tried to include all that are commonly available. And we added one more-a single piece of polypropylene, partly out of curiosity but also to discourage the use of this inexpensive type of line for anchoring. The polypropylene in the test just happens to be made by Wellington.
Because prices range widely, it should be noted that there is an equally wide range of quality in modern rope, whose manufacture has become very technical.
Most anyone can pick up a piece of three-strand, twisted nylon and tell-by feel and by looking closely at its fibers-whether it was made by what is called a three-stage or four-stage process. Three-stage line usually is soft and limp. Its so limp, its difficult to splice because the strands must be continually twisted while tucking. Four-stage rope, which includes a lot of extra bundling and twisting, is firmer, more compact and has more twists in a given length.
Of course, any line can be made to appear firmer by setting up the machine to increase the twist and tension. The machine can be adjusted to produce a soft, medium or hard lay. Mountain climbers use hard line that is much stiffer than that usually chosen by a sailor. A cowboys lariat is so hard and stiff (thats why he can lasso those frisky steers) that can’t really be knotted.
Single-braid or plaited line made of nylon is less susceptible to the soft-hard considerations. In fact, some of the loose braids, like Yales Brait, make ideal anchor rodes with amazing energy-absorbing qualities. However, they still require careful manufacture to assure that each filament and strand has the same tension.
Although they are ideal for the purpose, braids and plaits are not used as anchor rodes nearly as often as laid line-the three-strand, twisted variety. It may be because braids and plaits are more expensive and are more difficult to splice, or that when someone sees a braided line, the assumption is that its Dacron, which lacks the stretch to make a good anchor line.
Stretch Is Very Desirable
Stretchiness is very desirable in an anchor rode-to snub and spread out the outlandish loads created by surging, from wind gusts, in waves and when a boat sails its anchor. The inherent stretch in nylon is very valuable…not only to keep the rode from breaking, but as a shock absorber for deck hardware. Good nylon stretches about 25% of its length at 50% of its breaking strength and when very heavily loaded can visibly be seen to have a reduced diameter. Nylon line recovers from such loads better than any other line.
Nylons only negative is that when wet it temporarily loses about 15% of its strength. When calculating loads very accurately (which is done sometimes in the construction or utility business), this must be taken into consideration. With the safety margins usually selected by boat owners looking for a good anchor rode, it doesn’t matter much.
There are but a few manufacturers of the raw nylon filament, but each rope manufacturer boasts of combining a coating (to waterproof and lubricate the filament) and careful machine work to produce a balanced assembly that assures that every filament is doing equal duty. The coating, by the way, means that its not a good idea to wash lines in detergent.
Generally speaking, nylon also has better abrasion resistance than other synthetics. There is a considerable difference of opinion about whether laid line resists chafe better than braid. The laid-line argument is that less of the surface of the line is in contact with whatever is trying to damage it. The braid makers claim that laid line tends to chafe because the high points of the strands concentrate the wear, whereas braid has a smooth even surface that spreads out the wear.
If youre the careful sort who tapes or otherwise protects line wherever it is subjected to unusual wear, the argument lacks meaning.
The Bottom Line
So, if you like the shock-absorbing and easy-to-stow characteristics of a rope rode, what line to buy for your new anchor rode?
It may be worth saying that some economy of purchasing is available if you buy one kind of nylon line for both your anchor rode and to make up four or five docking lines, including several longish ones for springs. If you want colored line, bear in mind that dyed filament drives the cost up about 50% and theres also a slight loss in strength. The colored-line penalty is especially severe in laid line because its all colored filament, whereas a colored braid always has a white core.
Whatever you choose, youll probably be using it with a goodly length of chain (a boat length is whats often recommended). Short lengths of chain add little catenary. The chain is to withstand abrasion and damage from contact with whatever it encounters on the bottom.
Next comes the question of laid or braid or plait. Compared with double braid, laid line is stretchier, has superior chafe resistance and is easier to splice. Braid is stronger (for a given size), stows better and is nice to handle. Single-braid or plait is more difficult to splice, but stows well (because it is so limp) and is a whiz at handling shock loads.
If its braid you prefer-and why not?-wed be tempted, if we had a big boat to use New Englands handsome Mega Braid (5/8″ is the smallest it comes). Wed also like to try a rode of Yales Brait (very similar in feel and appearance to Mega Braid), because Yale claims it has outstanding energy absorption (78% greater than laid line and 85% greater than double braid). However, for braid, the conservative choice is Samsons 2-IN-1 double braid, mostly because Samson seems to have the edge in abrasion resistance. Its expensive. For a lot less money, either Wellingtons Braid-on-Braid or Samsons Super-Strong seems close enough in abrasion-resistance to earn a Best Buy classification. (Wellington line is heavily favored in the BOAT U.S. catalog.)
If its laid line you like, we think New England Ropes Premium nylon is the best in the business. The line seems to have the right combination of coating and density to be nice to handle and easy to splice. Most importantly, for abrasion resistance, braid or laid, its in a class by itself. Other premium brands of three-strand laid line may be cheaper, but none is enough cheaper to warrant a Best Buy label.
The Bottom, Bottom Line
And the ultimate choice of an anchor rode, at 4 a.m., in a too-open anchorage with 4′ swells and a 30-knot wind thats shrieking in the rigging?
Ignoring any braid/laid preference, our choice would be New Englands Premium three-strand nylon, with any chafe point wrapped and taped with our favorite sacrificial chafe guard-torn up strips of cotton toweling, tightly wrapped and taped securely at the ends.
With chafe-resistance superior to any other line, New England Premium is the one that will come closest to giving you what is hard to come by at anchor-a good nights sleep.
Contacts- New England Ropes, 848 Airport Rd., Fall River, MA 02721; 800/333-6679. Yale Cordage, 26 Morin, Biddeford, ME 04005; 207/282-3396. Samson, 2090 Thornton, Ferndale, WA 98248; 360/384-4669. Wellington, Monticello Hwy., Madison, GA 30650; 800/221-5054. Crowe Rope, Box 600, Waterville, ME 04901; 207/877-2224. Columbian Rope, Box 270, 145 Towery, Guntown, MS 38849; 800/821-4391. Pelican Rope Works, 4001 W. Carriage, Santa Ana, CA 92704; 800/464-7673.
