Upgrade your Sailboat to Roller Furling

By Tom Burden, Last updated: 6/17/2019

Tired of lugging a heavy genoa up the companionway? Had enough of flaking big sails? The time to upgrade your sailboat to a roller furling system is now. Roller furling systems have made managing headsails easier for about 30 years. If your boat has never had a furling system, or if the furler that’s installed needs replacement, there are more choices available than ever, and the products are all pretty efficient. Whatever type of sailboat you own, there’s a roller furling system that will simplify your sailing.

What type of sailboat do you have?

Looking forward thru cockpit dodger window

Our friend’s Catalina 350 had a Schaefer furling system for the headsail, and in-mast furling for the mainsail. The owner, who was in his eighties, regularly daysailed with passengers who were non-sailors. Just pull a couple of lines to douse both sails!

Dinghy, beach cat or small sportboat: Small Boat Furlers mount on the headstay on a sportboat or the jib’s luff wire on a dinghy or beach catamaran. Most sportboats, such as my Ultimate 20, use a separate halyard and a jib that zips over the headstay.

Trailer sailer: In general, we recommend furlers with a flexible extrusion, like Schaefer’s SnapFurl 500 or SnapFurl 700 system, for a trailerable cruising style boat. This is not a hard and fast rule, as many owners of trailerable boats have rigid aluminum furlers like Harken’s MKIV Unit 0, designed for 22' to 30' boats. However, if you frequently raise and lower your mast, as many trailer-sailers often do, a flexible furler will be easier to store and less prone to damage.

Bigger boat that’s stored in a slip: Larger sailboats have a wider range of choices because they operate with a bigger variety of headsails. The rest of this Advisor will help owners of bigger sailboats with this choice.

Are you looking for a structural headstay furler, flying sail furler or top-down furler?

Headstay-mounted structural foil furlers

The oldest and most common type, so-called structural furlers control your jib or genoa, and are installed over your boat’s headstay. Usually, a single furling line rolls the sail onto the headfoil extrusion mounted over the headstay wire. You can either furl your sail completely, or partially reef it to reduce area.

Flying sail furlers

If you are like a lot of sailors, you may be familiar with the concept of “flying sail furlers,” and you probably associate them with high-performance (and high-dollar) racing boats. Think again. Flying sail furling systems also offer simplicity, convenience and improved performance for cruisers. While long-distance cruising sailors must prepare their boats to withstand storm conditions, most of the cruising we do consists of light winds, often proceeding under engine power. Here is where flying sails and their new technology can help you sail more, motor less, and pay for themselves in reduced fuel costs.

Looking forward from cockpit toward bow

This Ultimate 20 has a Harken 436 Small Boat Furler. Nobody has to go on deck to handle either the jib or the retracting bowsprit for our blue asymmetric spinnaker.

Types of sails: Flying sail furlers are designed to be used with light and heavy flying, asymmetrical sails, at heading angles between a close reach and a broad reach. Examples are light sails like a gennaker, code zero, screacher, light or multi-purpose genoas, fisherman, or heavy sails: solent, reacher, staysail, storm jib.

Can I sail with my sail partially furled?

No, the flying sail furlers are made to sail with the sail fully unfurled. You cannot reef, or partially furl, your code zero or other flying sail. It is an “off or on” sort of technology, with a continuous-loop type of furling line.

Where can I buy an anti-twist “Torque” rope?

We sell furler cable in two diameters, so that you can make it yourself or work with the sailmaker of your choice. You can also contact our experts at West Marine Rigging Service, and we can fabricate this for you.

Can I use my current sail?

Yes, however a sailmaker must integrate the anti-twist cable into the luff of the sail, except in the case of top-down furlers, as discussed below.

Top-down furlers

The latest development in flying sail furlers, top-down furling systems fit downwind sails with a soft luff and full midsection. The sail starts furling from the head and continues down to the bottom of the torsion cable (hence the term “top-down furler”. Only the head of the sail is attached to the torsion rope, the rest of the sail is independent from the furler, and the tack is connected to a floating ring on the lower drum, allowing it to remain stationary while the drum turns. The sail deploys easily and rapidly, without the crew needing to leave the cockpit. Usually, a top-down furler does not require any modification to your existing sail.

A bowsprit (like those from Selden) is often a good idea to increase the gap between the furler and the headstay, but the furler can also be attached directly to the bow, depending on your boat. Ronstan offers top-down versions of their Gen 2 Flying Sail Furlers. Karver is also now making this style, in their KSF top-down furlers.

What are the measurements you need to know?

To shop for a furler you should know your headstay diameter, whether wire or rod, overall length (pin-to-pin measurement), and clevis pin diameter. If you are replacing or adding a furler, plan to replace your headstay. It holds your mast up, and you’re getting ready to put a system over it that makes it virtually impossible to inspect for wear or failure. A few hundred dollars for new wire will seem like pennies if you’re stuck with a catastrophic failure while cruising.

DIY-friendly installation

If you’re good at do-it-yourself rigging projects, installing a furler is a weekend task that the average boat owner can handle. Most Harken and Schaefer furlers are designed for owner-installation. Work with your local rigger if you are in doubt concerning your rigging skills.

Would you like a furler with a drum you can remove for racing?

Ultimate 20 sailboat going to weather

The jib on our Ultimate 20 has special vertical battens that work with the furling system.

Racers want to save weight in the bow, position the tack of the sail closer to the deck, and make headsail changes as the wind increases or decreases. Harken’s MKIV furlers allow these racing performance changes. They have split furling drums that are removable, and an aerodynamic Air Foil® extrusion with twin grooves for quick sail changes. Independent head and tack swivels help improve sail shape. Harken’s ESP furlers have fixed drums, round, single-groove foils and fixed halyard and tack swivels. Facnor’s LX Series, as well as Profurl’s Racing and Cruising furlers, offer similar choices

What accessories do you need?

Make sure to order the necessary terminals, furling line and toggles or Leg Kits to complete your installation. You often need to cut the headstay length slightly, and add a Sta-Lok or Norseman terminal.

Sail modifications: If your existing jib is hanked onto the headstay, you”ll need to replace the hanks with #5 or #6 luff tape. You may also install a foam luff pad for reefing deep draft sails. It allows the center of the sail to maintain an aerodynamic shape when partially reefed, without the draft moving to the back of the sail. Add a Sunbrella sun shade to the leech and foot if the sail will be exposed to the sun for an extended time period. Better yet, replace your tired, blown-out genoa, and buy a new sail with these modifications designed into it.

Leading the line aft: You’ll want lead blocks to control the system from your cockpit, with a ratchet block to help manage the load on bigger systems.

Halyard restrainer/halyard deflector: You may also need a halyard restrainer, which keeps the halyard from wrapping around the forestay.