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Install ratlines for better visibility

Jan 1, 2003

To those sailors who are used to sailing in typically well-charted and buoyed temperate waters, the realities of navigation in tropical seas can come as an unwelcome surprise. Many charts of the tropical Pacific are based on surveys made 100 years ago; consequently, the charted latitude and longitude of reefs and islets often disagree with GPS fixes by several miles. In addition, navigational markers are frequently absent or in disrepair. Compounding the challenge, the principal hazards coral reefs can be very difficult to see, except at low water with the sun overhead. These factors combine to make it imperative that one return to some of the age-old traditions of navigation, such as taking frequent visual bearings, maintaining an accurate DR track, and keeping a good lookout aloft. The latter is often the only defense against disaster when making a landfall or entering an anchorage in reef-strewn waters.

The improvement in visibility that one gains when 15 or 20 feet above the deck is remarkable and can turn a nerve-wracking sail through a narrow pass into a simple "sail by color" exercise, using the color of the water for staying off the coral. The key is to get aloft safely and comfortably. We have seen many voyagers picking their way through shallow waters while one crewmember perches atop the bow pulpit, or balances precariously on mast-mounted halyard winches. We used both of these approaches in making our first South Pacific landfall, a coral atoll whose pass was marked only by the wrecks on either side. Once safely anchored, we swore that when we threaded our way back out, one of us would be properly aloft. Our solutionfashioned in a few days within the tranquil waters of the atoll's lagoonwas a set of rope ratlines for our 35-foot sloop.

Rope ratlines are probably the oldest method of getting aloft, but they are also one of the best. They are inexpensive, easy to make, and secure to use. And, unlike wood ratlines or mast steps, they can be fashioned or repaired using materials and tools that are probably already on board. The first consideration in making rope ratlines is the type and size of the line. Three-strand Dacron is the optimum line as it is easy to splice, low stretch, and UV resistant. If you don't have access to three-strand Dacron, nylon anchor rode can also be used. The line should be 3/8-inch to 1/2-inch in diameter. While 1/4-inch may be strong enough to support most people's weight, it would be uncomfortable to stand on for any length of time, whereas line larger than 1/2 inch is awkward to splice in the short lengths that the ratlines require.

Spend time on aligning the lowest rung, as all the rungs above will be based on it. To begin, determine how high you want the lowest rung to be (ours start 30 inches above the deck). Mark the aft lower shroud at this point (a permanent felt-tip marker works well). Next, using the horizon as your level, sight over to the forward lower and mark it at the same height. Don't follow the line of the shear or your ratlines will slope uphill. The next stepapplying service to the shroudsis a vital one if your ratlines are to stay in place; this is especially true with stainless-steal rigging. The service should extend for about three inches, centered at the spot you've marked for the ratline. Traditionally, service is applied after the wire has first been parceled, friction tape being the modern parceling material of choice. The idea behind parcelling is to keep moisture out of the wire's interior. Because we are parcelling only short sections of wire, it seems doubtful that the parceling will be effective. In any case, we had none on hand at our mid-Pacific atoll, and eliminated this step. If you intend to parcel the shroud, do so for the same three inches, working up from the bottom with the lay of the wire.

The service is applied from the top down using waxed sail thread. Take about three feet of thread and tie it to the shroud using a constrictor knot. Apply firm, even pressure on the sail thread as you make your turns, ensuring that there are no gaps between them. When you reach the bottom of the section to be served, make three or four loose wraps. Draw the remaining line up through the loose wraps and tighten, being careful not to overlap the wraps. Trim any loose ends and then repeat the process for the other shroud. You may wish to apply a second layer of sail twine service over the first to ensure a good gripping surface on which to lash the rungs; we experienced a small amount of slippage on ratlines lashed to single-layer service, while those lashed to twice-served shrouds have not budged.

You're now ready to splice the first rung. To start the splice, take a piece of 1/2-inch line and, using waxed sail thread, tie a constrictor knot around the line about five inches from the end. Bend the end over to form a small eye about one inch in diameter with the constrictor knot at the throat of the eye. Unlay the five inches of line so that you end up with three individual strands. Apply tape to the ends of each strand to keep them from unlaying (using different colors is handy to differentiate them as you splice).

Tuck the left-most strand under, over, and under against the lay of the line. Now take the middle strand and tuck it under where the first strand went over. Turn your work over and tuck the third strand under the remaining standing strand. Next, make four more series of tucks, starting each time with the first strand. Note that, after the initial tuck, strand one is passed under only one standing strand, in the same manner as the second and third strands. Roll your work between your hands after each series to settle out the tucks. Once the splice has been completed, cut off the remaining ends with a sharp knife and melt with a lighter. Ideally, you should whip the end of the splice to ensure it does not come undone, but ours are doing fine without this extra step. Before you splice the other end, hold the spliced eye against the shrouds as if it were already lashed to the rigging and mark the line where the center of the other eye should be. The two eyes should just touch the rigging. (Once it's lashed and stood on a few times by the heaviest crewmember, it will take on a bit of a bend.)

With eyes spliced at both ends you're ready to lash your first ratline to the shrouds. We used small, braided nylon twineuse whatever is handy, just make sure it's strong. Begin by tying a length of the twine through the eye of the ratline. Pass the twine around the shroud and back through the same side of the eye and pull tight. Repeat this square turncoming out of the eye, around the served shroud and back through the same side of the eyeuntil the lashing covers about one inch of the shroud. Now take several frapping turns around the lashing at the tip of the eye, using a marlinespike hitch if necessary to apply tension. Finish the lashing with several half hitches. Repeat the process for the other side of the ratline. You have now only to test the resultssome vigorous jumping on the rung should do it.

Repeat this procedure for the remainder of the ratlines and you'll have a dandy ladder ready to take you aloft at any time. The procedures for the upper ratlines vary only in that you'll need a bosun's chair to properly measure the length of the upper rungs, as you'll draw the shrouds together if you measure while standing on the lower rungs. You may also find it easier to serve and lash from the bosun's chair, as that way both hands are free for the work. Finally, although a set of ratlines on one side of your rig is far better than none at all, we strongly suggest that you have ratlines on both port and starboard, as it's impossible to see through the headsail when your ratlines end up on the lee side.