The debate over what constitutes a proper anchor rode may be as old as rope and chain. In fact, each has its own strengths, and sailors can tailor their anchoring systems to suit their boats and the waters they sail.
|Rope to Chain |
Even anchor line "scope" can be elusive depending on which sailor you're discussing it with. Scope numbers used here will refer to the length of the rode divided by the vertical distance from bow roller to seabed at high water. Since height of bow off the water is part of the equation, different boats figure scope differently. And don't neglect the tide -- scope changes radically with depth of the water.
Here are some thoughts:
All chain advantages:
|Anchor and Chain Stopper |
Chain is heavy. This weight allows less scope to be used since the wind has to blow hard to lift all that weight off the seabed. All chain rodes can be allowed a scope of 3 in light conditions and run to 5 or 6 for heavier weather. Chain is heavy. Boats have a difficult time dragging this weight through the water and over the sea floor. Thus boats wander, or "sail", around their anchors much less. Oddly, light boats with fin keels could benefit most from an all chain rode, but are least likely to have one. Chain is much less prone to abrasion than cordage. It stands up to the abuses of coral, sharp rock, shells and bottom pollution.
All chain disadvantages:
- Chain is heavy. It is awkward to use without a windlass and can be dangerous if not handled properly. It adds considerable weight to the bow of the boat - the least desirable place.
- Chain is expensive. Almost 7 feet of Nylon rode can be purchased for the cost of 1 foot of chain.
- Chain rusts. Even the best hot dipped galvanizing fails rapidly when immersed in salt water 365 days a year. Eventually it will stain chain locker, deck and associated hardware. Re-
galvanizing is becoming harder to find and more expensive.
|Chain Hook and Bridle Plate |
- Chain is inelastic. When it finally blows hard enough to straighten the chain out, it will snub hard against cleats and chocks. A length of Nylon line must be used as a snubber to take these shock loads.
- Chain is weak. Even hi-tensile chain has less than half the breaking load of a suitably sized Nylon line.
Nylon line advantages:
- Line is readily available at attractive price, especially three strand twist.
- Nylon line is reasonably light, easy to handle and stow. Spare rodes are easy to coil away in the bilge. Single and double braid remain supple longest, but have less of the desirable stretch than three strand.
- It is far easier to set a second anchor from a dinghy if it is on a Nylon rode.
Nylon line disadvantages:
- Nylon requires more length - usually 6 to 7 scope for light weather up to 10 for heavy conditions.
- Nylon wears easily. Chafing gear must be maintained assiduously. Rough seabeds of shell or coral must be avoided and the rode must be condemned if cut. ® Nylon looses strength when wet for extended periods. Sailors need to go up a size to gain adequate strength.
- Nylon lets the boat sail around her anchor a great deal.
Thoughts on rodes:
- Follow local custom. There is little more embarrassing than sailing around on Nylon while the boats around you are on stable chain, or vice versa.
- All rodes need to be marked at intervals understood in daylight, darkness, and when panicked.
- Old standards (one foot of chain per foot of boat) leave much to be desired. Weekend cruisers and club racers anchoring infrequently in light conditions may be OK with very little chain. Full-time liveaboard cruisers may prefer all-chain.
Customize the length of chain to fit your needs. Shallow draft boats anchor in less water and therefore need less chain to have adequate scope. Ketches, schooners, boats with big pilothouses or lots of other windage aloft need more chain. Boats cruising the shallow US East Coast need less chain than those anchoring in the deep Pacific.
|Anchor Swivels and Shackle |
- All chain rodes need a snubber. A common fault is to have a short fixed length snubber. When the wind pipes up at 2am, simply slipping more chain and snubber line over the side is convenient. Our snubbers are 65 feet long.
- Sentinels, heavy weights run down to the middle of the rode, are not only valuable in extra-heavy weather, but for "Bahamian" mooring in areas where tide runs strongly against wind. The sentinels are used to keep the slack rode from chafing against the hull.
- Turn Nylon rodes end-for-end periodically. We splice a stainless thimble in each end, rotating when we note wear near the anchor chain.
- The bitter end of all rodes should be secured to the boat in such a way that the connection can be undone from the deck quickly.