Stopping Mainsheet Twist

A new boat offers new opportunities to apply some more anti-pretzel logic.

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The dinghy requires a gorilla to hoist onto the davits. The mainsheet won’t release in a gust. The internal reefing line inside the boom is stuck again, making it impossible to pull the tack and clew in tight. Twisted tackle complaints like these are common, and yet completely preventable.

Although rigging changes can alleviate some of these problems, the most common cause is poor coiling. We’re not talking about a neatly coiled line versus a sloppily coiled line. The problem is coiling . . . period.

I never experienced mainsheet tackle twist on my first two boats. On performance beach cats, the bitter end of the mainsheet is secured to the tramp. Slack is controlled by a bungee system that prevents the sheet from dragging in the water or from being washed off the deck by a wave while you are hiking out at the helm.

Similarly, the mainsheet of my Stiletto 27 was secured to the deck because the cockpit could be swept by waves in wild conditions. By maintaining tension and constraining the ends, we prevented twists from entering the line. Tangles are also eliminated. A tangle-free mainsheet run is vital on boats that can capsize if the sheet does not pay out smoothly in a gust.

Stopping Mainsheet Twist
Occasionally spinning the twists out of the mainsheet will prevent it from getting twisted at the worst possible moment.

PREVIOUS OWNER TWIST

My PDQ catamaran introduced me to tackle twist. The dinghy davit tackle repeatedly twisted because the previous owner loved to neatly coil the tails on the cleats. Every time he coiled the tails he introduced twist, and when the dinghy was lowered, the twist was sucked into the tackle. There were also too many swivels in the tackle. We redesigned the tackle without swivels and thereafter simply tossed the tails in the dinghy without coiling. With these simple changes, my 13-year old daughter could easily operate the tackle and borrow the “family car” for beach expeditions on her own.

The internal reefing tangles were also tightly snarled because of previous owner’s coiling errors. Because we could not pull the blocks out or even pull the line from block-to-block, all we could do was laboriously force a counteracting twist into the locked-up lines, inch-by-inch, until they ran smoothly again.

To prevent recurrences, we secured the bitter ends of all reefing lines and halyards to the cabintop padeyes. As with a beach cat, if the tail is constrained there can no net twist available to be sucked into the boom or mast by accident. Fifteen years have passed since the great reefing line tangle, and I still remember vigorously cursing the previous owner’s obsession with neat but non-functional coiling.

Stopping Mainsheet Twist
The zip ties locking this mainsheet last for at least a season, if not more. Lashing with waxed twine will last longer in the sun.

The mainsheet twist was caused by a series of turning blocks that led the along the boom to the mast and back along one side of the cockpit to a winch. The solution was to lock some of the tackle swivels, so that twist would be forced out when the sheet was eased (see “Undoing Mainsheet Twist,” PS February 2018). Once a year we would pull the tackle block-to-block and re-reeve the turning blocks to begin with a fresh start.

Stopping Mainsheet Twist
A rope will automatically make a figure 8 if you don’t twist it.

FACTORY TWIST

Another type of tackle twist begins in the factory or marine store, where the rope is neatly coiled. (Hose is also be vulnerable to this.) During packaging, the line from larger spools are loaded onto smaller spools without a twist. As long as you load these lines from the side of a turning spool onto another spool—a fishing reel for example—they won’t twist and are ready to use. But when you pull line off the end of the spool, as you might for a halyard bought on a spool, a ½ twist is introduced for every revolution. Similarly, if you hoist a halyard up the mast straight from a store-bought coil laid on the deck, without first carefully flaking out the line and removing twists, the twists will be stored in the mast or tackle, ready to cause mischief as soon as the lines are tensioned a few times and settle in.

REMEDY #1: FIGURE 8 COILING

I was taught this coiling method by my father 50 years ago. We had an electric mower and a large yard to mow. In my other passion, rock and ice climbing, I coil 180-foot lengths of climbing rope in this way one after another, multiple times each day, with no tangles. Lay the coils into your hand, one on top of the other, letting them fall as they may. The loops will naturally form a sloppy looking figure-8 mess, but it won’t be tangled. Avoid the natural tendency to roll your wrist very slightly when passing the rope from the pulling hand to the gathering hand; cumulatively, that quarter roll can induce a lot of twists.

There are many variations on securing the coil, depending on whether it will hang on a cleat or lie in a locker, and insisting your method is best will start a dockside argument as fast as declaring the one true way to tie a cleat hitch. Perhaps the simplest locker method is this: Secure the top loop tightly just below your hand with 4-6 wraps of the tail, leaving several feet of excess tail. Pass the tail through the hand loop as a bight, and then pull the tail through the bight. Snug the wraps up against the tail knot and pull tight.

The key is to pass the rope from hand-to-hand without twisting the rope at all. Watch for the telltale Figure 8 loops.

Stopping Mainsheet Twist
As long as we properly flaked the tail, the mainsheet remained twist-free long after our 4-hour test.

REMEDY #2: OVER-AND-UNDER COILING

Coil the hose onto the deck (or in your hand), making the first circle in the usual manner. On the second circle, flip the coil under so that it lands in reverse, counteracting the 1/2 twist the first turn created. Repeat. It’s easier when you can watch it being done. This is the standard method for hoses, stiff cables, and large lines that are coiled flat, since they don’t like making figure 8’s. https://www.youtube.com/watch?v=p3LD6CL_83o

REMEDY #3: FLAKE IT.

Any line that will need to run out quickly and smoothly, including sheets, halyards, and anchored rodes, must be flaked out first (a neat over-under coil may also work if the rope is withdrawn vertically). Avoid a neat Flemish coil, because that will twist just as badly as the store coil we all hate.

A functional flaking job is not just a pile of rope. It must start with the bitter end on the bottom, with subsequent layers built one by one on top of that. The simplest method is to place the rope on the deck as though you are making a figure 8 coil, but without holding the loop. Done smoothly, it will take on a sloppy figure-8 shape naturally. Don’t just throw a pile of rope at the ground; there will be twists, the rope will have to pull out from under subsequent layers, and kinks and knots will pull in the tackle.

Always coil or flake towards the end you intend to use first, so that the turns you need first are not buried at the bottom of the coil or flake. When coiling a hose, stand near the spigot and pull the hose towards you. When coiling halyards and sheets start at the bitter and coil towards the tackle. Always coil towards the working end.

Stopping Mainsheet Twist
The tail of this mainsheet was coiled “neatly” each time it was pulled in, resulting in a twisted tackle after just four hours of active sailing.

TWIST PREVENTION

Periodically work the twist out. Most likely you will not need to fully unreeve the tackle. Remove it from all of the turning blocks and pull the tackle block-to-block by loosening the toping lift, or removing the top shackle if need be. Flake the line out twist-free, spinning the twists out through the tail. Pull the blocks apart, sucking twist-free line into the tackle, and repeat as necessary until the tackle is no longer twisted.

SWIVEL ASSESSMENT

We still believe in eliminating swivels. Don’t buy a swivel block for a multipart tackle, believing it will work more smoothly, unless you are absolutely certain it is needed. The attaching shackles generally provide all the motion that is needed, and you can always add one if more freedom of movement is needed.

Twist prevention is particularly relevant to internal reefing systems, where the twists can work their way inside the boom, snarling tackles and rendering reefing impossible at the worst possible moment. Since you cannot easily force the pulleys block-to-block, it may be necessary to force a correcting, reverse-twist into the line with your fingers, and reef and unreef several times to pull the correcting twist into the tackle.

With a helper to pull the clew reef lines out, detangling can be done without hoisting sail. The culprit is usually turning blocks, and you might have to do this several times each year, depending on use and design. The longer you wait, the harder it is to unsnarl, because the lines can really lock up around each other.

Securing the tails will also prevent this, though it is only practical if the lines are managed at the mast.

CONCLUSION

Ropes love to twist, and when they twist, they love to tangle. Fight twist. The most effective strategies are securing the bitter end and functional coiling.

Bye-bye Square Rigging

In addition to properly flaking lines, minor changes to the multi-purchase setups can prevent twists. Here are some suggestions from Part 1 in this series (PS February 2018, “Undoing Mainsheet Twist”).

Fiddle Blocks. These are always rigged in one plane, using a simple outward spiral pattern. None of the internal blocks should swivel; a swivel there solves nothing and leads to friction. A swivel at one end may be useful, but more often fixed blocks are better.

Stopping Mainsheet Twist
A 90-degree twist in these dinghy davits eliminates the “square” rigging in the setup that can exacerbate twist

Double and Triple Blocks. If these are rigged for 4:1 purchase or 6:1 purchase, the problem is nearly always square rigging. An imbalance in forces due to bearing friction, line friction, and sometimes an offset pull on the final exit twists the blocks, cause the ropes to rub and the lines to run crooked in their pulleys. The solution is cross-reeving. Instead of following common sense, winding the lines from right to left in square pattern, lay the blocks at 90 degrees.

Drew Frye, Practical Sailor’s technical editor, has used his background in chemistry and engineering to help guide Practical Sailor toward some of the most important topics covered during the past 10 years. His in-depth reporting on everything from anchors to safety tethers to fuel additives have netted multiple awards from Boating Writers International. With more than three decades of experience as a refinery engineer and a sailor, he has a knack for discovering money-saving “home-brew” products or “hacks” that make boating affordable for almost anyone. He has conducted dozens of tests for Practical Sailor and published over 200 articles on sailing equipment. His rigorous testing has prompted the improvement and introduction of several marine products that might not exist without his input. His book “Rigging Modern Anchors” has won wide praise for introducing the use of modern materials and novel techniques to solve an array of anchoring challenges. 

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