Sails

Furl it Up

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Though most sailing innovations are born on racing boats, cruisers can take credit for pioneering and popularizing the concept of the modern furling headsail. After cruisers tested and perfected these systems about 30 years ago,  they were widely adopted on certain types of raceboats. Since then, however, there’s been an interesting reverb effect, in which offshore racers have created ever more refined and versatile furling technologies that are now trickling back into the cruising community.

Most innovations have grown out of the development of large light-air headsails (see “Engine Savers” on pg. 46) that furl on their own luffs and can be easily hoisted and doused while rolled up on themselves. Initially, such systems tended to be fairly facile, employing light twin luff lines sewn into the sail to create a twist-resistant spine and lightweight single-line drum furlers similar to those used in conventional jib-furling systems. Equipment like this is still available, but the more refined systems now feature specially woven “anti-torque” ropes (usually just called “torque ropes”) and sleek low-profile continuous-line furlers. Such kit is currently standard equipment on many raceboats and is increasingly popular with cruisers.

A nice bit of kit from Karver: a wire structural furlerWhat to look for

Continuous-line furlers, sometimes called “code furlers” (after the large “Code Zero” sails they were first developed to work with), are now produced by every major sailing-hardware manufacturer, as well as several minor ones. The basic concept is quite simple: instead of using a single straight line that rolls up on a drum to furl a sail, a continuous loop of line is run through a flat furling spool. These spools ride much lower to the deck than drums, thus maximizing a sail’s luff length, and there’s never any problem with not having enough line to roll a sail all the way up.

There are some things to watch out for. First, a good continuous-line furler should be designed so that the furling line can be installed without disassembling the furler itself. The teeth in the jaws of the spool must also be aggressive enough to grip the line firmly so it doesn’t slip when a sail is rolled up. Ideally, the line should fall out of, or be held away from, these teeth when the sail is unfurled, so the spool can spin freely. The spool itself should have a reasonably large outer diameter to increase leverage when the sail is furled in again, and should have an effective line-feed mechanism to keep the line from tangling. Finally, there should be a reliable quick-release mechanism for connecting the thimble of the sail’s torque rope to the body of the furler.

Karver's KF0H halyard lock. A light halyard pulls the sail's top swivel onto a male fitting that is secured to the mast.Careful thought must also be given to the halyard supporting the sail. A torque rope in the luff of a modern Code Zero-type sail must serve both as an effective furling spine and will in many cases also temporarily carry the equivalent of a full headstay load. This means it should be set up bone-tight, particularly if you want to keep the sail’s luff as straight as possible. Most rigs designed to fly such sails feature 2:1 high-modulus headsail halyards with a turning block on the halyard just above the top swivel.

If retrofitting a code furler and sail onto an existing rig, it may be difficult or impossible to create a 2:1 halyard purchase. In this case, a high-modulus one-part halyard can be used and ideally should run to a dedicated (preferably slightly oversized) winch. A single rope clutch will not be sufficient for carrying the load, though two clutches, in a pinch, might serve. If a spinnaker halyard is used, you’ll also need to upgrade to a larger halyard block and may need to reinforce the halyard crane at the masthead as well.

One manufacturer, Karver, does offer a unique solution to the problem of halyard loads. Its patented KF-H headsail-furler halyard lock allows you to hoist a torque-rope swivel with a female orifice on to a male fitting fixed on a mast. The sail is hoisted, and a firm tug on the halyard locks the upper swivel in place. Tension can then be taken on the sail’s torque rope with a multi-part tackle under the furler. The halyard itself carries no load at all, and hence can be a light one-part line. Another tug on the halyard releases the lock and allows the sail to be lowered again.

Structural furlers

Because a fiber torque rope is significantly lighter than a conventional solid furling rod with a wire stay inside it, many performance sailors now prefer to set up headsails on code furlers as permanent parts of their standing rig. These so-called “structural” furlers are engineered to carry full headstay loads on a full-time basis.

Modified masthead on a typical cruising boat with a larger halyard block and reinforced crane to support a furling sail and torque ropeFor those looking to make such rigs more versatile there are some variations. Both Karver and Facnor, for example, offer systems where continuous-line furlers can be set up on structural wire stays to which different sails can be bent on with a zip luff or traditional hanks. This saves the weight of a solid furling rod and allows you to remove and change out sails as you would with a conventional furler. However, as with all the torque-rope systems discussed above, you cannot use a structural wire (or torque rope) furler to reef a sail by rolling it partway up.

Inevitably, to roller-reef a headsail you must have a solid rod to roll it up on. If you’re willing to accept the extra weight of the rod to gain this ability, you can still use a low-profile furler to maximize luff length. Facnor offers a unique system, dubbed “RC,” that combines a modern continuous-line furler with a conventional furling rod set up over a wire stay. Its unique single-line FlatDeck furler, with a length of thin webbing that rolls up on a low-profile drum, also lets you roller-reef a sail with a longer luff. Several other manufacturers offer conventional single-line below-deck drum furlers that provide the same capability.

Spinnaker furlers

The latest advances involve furlers that can handle large asymmetric spinnakers. In most cases manufacturers have solved the problem of how to wrap a full-cut sail with a free-flying luff around a torque rope by creating “top down” furling systems. As we went to press, no fewer than five companies (Bamar, Ronstan, Karver, Seldén and CDI) had introduced, or were about to introduce, equipment of this type.

Again, the principle is simple. Once it is set and flying, the A-sail’s luff is entirely separate from the torque rope it was rolled up on when hoisted. The tack of the sail is set on a free-spinning swivel that rides on or just above the furler drum, while the head is fixed directly on the upper swivel that turns with the torque rope. When the time comes to douse, the sail is rolled away on the rope from the head downwards, depowering the sail as it furls.

The furler turns only the torque rope, which first reels in a short tether, then captures and furls the spinnaker from the middle of its luff


Only one manufacturer, Facnor, has dared to try something different. Its Asym-FX furler also leaves an A-sail’s luff flying free of its torque rope when set, but connects the two via a light tether line that runs from the middle of the rope to the middle of the luff. Both the tack and head of the sail are attached to free-spinning swivels, so that the furler turns only the torque rope. As the rope turns, it first reels in the tether line, then captures the sail’s luff at its midpoint and furls it up from there.

The Asym-FX system, on its face, is more complex than top-down systems. A sail must be modified with a mid-luff patch to accommodate the tether line which must be long enough to not interfere with the sail’s luff when flying, yet short enough to minimize furling time. Proponents like the system because it rolls up the most powerful part of the first sail, but top-down fans counter that the extra time spent reeling in the tether obviates this advantage. In our informal tests aboard editor Peter Nielsen’s boat, we found we could furl a typical cruising spinnaker with an Asym-FX furler in about 30 seconds. According to U.S. Facnor rep Dave Lively, some owners have improved the system by fixing solid larger diameter tubes on their ropes where the tether is attached, so that the tether rolls up faster still.

No doubt there will be further refinements as these and other modern furling systems become increasingly popular. Once seen exclusively on go-fast raceboats, manufacturers now estimate that 30 percent or more of the various continuous-line furlers they sell are going on to cruising boats. This proportion will certainly increase over time, as the dynamic of the business is inexorable. The more systems there are that make sailhandling easier, the more sailors there are, of all types, who will want to use them.

Selden's double cam cleat allows you to easily control a continuous loop of line, but can also easily be stowed away
Whither the Loop

One question that puzzles many sailors new to continuous-line systems is what to do with the great loop of line that drives the furler. The easiest­—but probably least effective—approach is to keep the loop short and leave it loose on the foredeck, made off to stanchion post or cleated somewhere when it’s not in use. This makes it easy to remove the line and its furler when you don’t want them on deck, but it also means you have to set and furl your sails from up forward.

You obviously need a much longer loop if you want to run things from the cockpit, and to keep the long bights of line from getting tangled or falling overboard, it usually makes sense to run them through dedicated fairleads. One common approach is to run the loop thru leads and hold it semi-taut by adding a floating lead on a bungee cord at the very end. You can also add a clutch to help control the line, but all of this, of course, makes for a more permanent installation.

If you want the security of a dedicated installation, but also want to maintain flexibility, you should check out Seldén’s double cam-cleat furling line control. It’s easy to install around a line and has a snap-shackle underneath that lets you set it up anywhere you want. I used one this summer after putting a code furler on my boat and found it offered the best of both worlds. I ran the loop aft outside of a midship stanchion post and secured with the Seldén cam-cleat just outside my cockpit. I could leave the line secured on deck when the boat was idle, or, if I wanted, could quickly stow everything away.

However you set up your furling loop, it’s a good idea to lead it so that you can get it to a self-tailing winch. On the whole, continuous-line systems have much less friction in them and work more easily than single-line systems, but there are times when you’ll appreciate the extra power and flexibility of having a winch at hand.


 

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