What Is The Best Anchor Cable: Chain Or Nylon Line?

Cruising sailboats rely on either nylon rope or chain to connect to their anchors. Here's a discussion of the advantages and disadvantages of each type of anchor rode.

Newcomers to sailing will get a lot of dockside advice on equipment choices, and much of this advice is based on personal biases and is inaccurate or in conflict with the observations of experienced cruisers. It can be argued that ground tackle (the anchor and connecting cable or line that attaches it to the boat) is the most important equipment on board a cruising sailboat. Good ground tackle will save your boat in situations where inadequate or improper ground tackle will let you down. Many are the ships and boats that have been stranded on beaches or wrecked on the rocks when their anchor line parted in a storm.

For the modern cruising boat, the two primary choices for the anchor cable (often referred to as an "anchor rode") are nylon rope and galvanized chain. Each has its advantages and disadvantages, which I will examine here so that you can make an informed decision as to which is best for your boat and your style of cruising.

Anchor rodes of nylon rope are most commonly seen on boats that are used for daysailing or short cruises near the home port. The primary advantage of nylon rode is that it is lightweight. This makes it the anchor rode of choice for smaller cruising boats and high performance racing boats or multihulls that are affected by every additional pound of gear. The anchor rode is usually stowed below decks at the bow in a special locker for this purpose, and a heavy chain rode carried this far forward could seriously alter the trim of a small, light displacement sailboat. The other advantage of a nylon anchor rode is its elasticity. This ability to stretch under load means that a nylon line connecting your anchor to your boat will put less stress on the cleats or other attachment points on your deck in stormy conditions that cause the boat to pull hard against the anchor. Proponents of nylon anchor rodes also argue this ability to stretch decreases the chances of the anchor being jerked free of its set in the sea bed.

Nylon rodes are never attached directly to the anchor, but instead should be connected to a short length of chain, which is then connected to the anchor. The reason for this is that sharp objects such as coral, rocks, or manmade debris on the sea floor could cut the nylon where it comes in contact with the bottom. A length of chain about equal to your boat length will help eliminate this risk. The added bonus of this length of chain is that its weight will hold it to the bottom and create a more horizontal pull on the anchor, making it less likely to drag in a storm.

All-chain rode is more commonly seen on world-cruising boats and bigger vessels that are not affected by the additional weight of a hundred or more pounds of chain. One advantage of all-chain rode is that less "scope" or length of anchor rode is needed with chain. The rule of thumb is that with nylon you need a length of rode equal to at least 7 times the water depth where you are anchored, but with chain you only need a length equal to 3 times the water depth. This is because the chain is heavy and most of the rode's length will settle along the bottom and achieve the desired horizontal pull on the anchor without requiring so much scope.

Chain is, of course, stronger than nylon and is less likely to break under load. It is impervious to abrasion on rocks and other rough objects and is not likely to be cut by anything under the surface. This is why world cruisers, who have to anchor in a wide variety of conditions, prefer all-chain rode. A nylon rode, as they point out, can be cut in seconds it if contacts the right sharp edge, and in some Third World countries it is not unheard of for a disgruntled or mischievous fisherman in a canoe to slice a nylon anchor rode with a knife while the occupants of the boat are asleep.

Chain is not as forgiving as nylon where it attaches to your boat, and in stormy conditions its lack of elasticity can cause the boat to jerk hard against the anchor, resulting in torn out deck fittings or the anchor breaking loose and dragging. If you use all-chain rode you will still need a short length of nylon or a specially-made rubber cord to rig up a "snubber." The snubber connects to the chain a few feet from the bow of you boat and is in turn made fast to the deck cleats. The chain is still secured to the boat as well, in case the snubber breaks. The snubber prevents the boat from jerking against the anchor by absorbing shock when wind and wave action would otherwise cause the boat to pull hard on the anchor.

Any cruising boat going places will need at least three anchors and rodes, and preferably four. This being the case, it pays to have both types of rode aboard if your vessel can handle the weight of chain. More important than the material the rode is made of, however, is the length. Make sure all your anchor rodes are long enough to allow you to put out the proper amount of scope for the water depths you anticipate anchoring in. For most places, this means carrying at least one rode that is 300 feet long.

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