Mainsail Roller Reefing
by Dick Harrington (06/29/00)

Cruising sailors are aware that a day will come when they will need to be able to reduce the size of the mainsail. 

The most common and popular method of doing this is slab reefing, sometimes referred to as "jiffy reefing”. This requires the installation (by a sailmaker) of reefing points (grommets) in the sail. There are usually two rows of reefing points, providing for a moderate reef and a deep reef. This system is called “jiffy” because, when properly set up (reefing lines rigged on the boom, etc.) reefing can be accomplished very quickly--in a couple of minutes or less. 

A second system which remains popular with some UK and Scandinavian Wayfarers is roller reefing, where the sail is wrapped around the boom. The design of the gooseneck on the Wayfarer makes this easy to do. This system has some advantages as well as disadvantages compared to slab reefing. Some well known and highly experienced Wayfarer sailors actually prefer it. 

Frank Dye uses a roller furling genoa and slab reefing on the main. However, when Frank gets caught out in some really heavy stuff and is still overpowered after reefing down to the second reef, he will reduce sail further by taking two or three wraps around the boom. He combines roller reefing with slab reefing. Now this is reefing!

Roller reefing requires all mainsheet blocks to be at the end of the boom and at the transom. The block located at the center of the boom and the block and jammer located on the back slope of the centerboard trunk, the typical setup over here, are not used. Sailors who regularly cruise and employ roller reefing have transom to end-of-boom sheeting as the standard. The jammer is mounted on the transom traveler (or horse). This is a perfectly good sheeting arrangement which unclutters the cockpit considerably, but it takes some getting used to. 

The two main disadvantages of roller reefing are: 

  1. 1. The forces from the sail impart a twisting moment upon the gooseneck and can actually break it.
  2. 2. Since the attachment of the boom vang/kicker also has to be modified, the vang becomes less useful as a means of controlling sail shape.
The procedure that follows employs expedient, or "make do", modifications to the mainsail sheeting and boom vang set up that allow you to perform roller reefing.

Roller Reefing - step by step

1. Heave to – unless you have the luxury of doing your reefing in a sheltered area. 

(Uncle Al’s note: Dick’s diagram suggests having the board part way up but it has been my experience that, unless you are in serious fear of hitting a lee shore, it is best to put your board all the way up once you have killed most of your forward momentum. Two major advantages of this approach are 
  • the boat cannot tack even with the tiller tied off to leeward
  • the boat will not trip over its centreboard in a bad gust
N.B. If you see a [thunder] squall coming, it is best to get all sails down and tied up, and try to put your transom towards the squall. This enables you to run before the squall under ‘bare poles’ at a surprising clip. Starting out head to wind will only make you go backwards at the same surprising clip, and sooner or later you will go sideways to the wind. This is not advised since a Wayfarer can be lifted bodily out of the water and capsized when a severe squall gets under the hull!)

2. Jib. If you are in a blow, or uncertain about conditions, take the jib down first. (It is convenient to leave the jib tack shackled at the bow and bundle & tie it on the foredeck to one of the deck handles.) Unshackle the halyard and make it fast.

3. Mainsail. Drop the main quickly to avoid starting the boat sailing when hauling in the boom. (Al’s note: This will be no problem if the board is full up!) Leaving a portion of the sail up, say about half, may help in maintaining hove to. Disconnect the boom vang.

4. Changing over to boom end sheeting. Un-reeve the mainsheet from the jammer, center boom block and any fairleads on the boom. Attach the center boom block to transom traveler by means of a bridle made from a short piece of thin but stout line. The ends of the bridle can be tied, using a bowline, around the traveler. Feed the loose end of the mainsheet through this block as shown in the diagram. Put a knot in the end of the mainsheet. A figure eight knot about 4 feet from the end of the sheet will keep it from inadvertently running out of the transom block. (Note: The lack of a jammer is not a problem and is safer in heavy weather.)

(Al’s note: If I were contemplating using this system to cruise, I would prepare such a short bridle in advance, complete with block and attachment points on the transom, and leave the mid-boom mainsheet block where it belongs. A cruising sail can be wrapped around this without damage, I would think!)

5. Boom Vang. If possible, tie a 3 to 4 foot piece of thin but strong line to the boom vang fitting on the boom. This will become a “Chinese jibe” preventer.

6. Cunningham Fitting. Install a shackle, hook, or loop of line, in the pin fitting on the boom (at the sail tack). This will serve as an attachment point for the Cunningham and will act to counter the twisting moment on the gooseneck. Pull the outhaul tight.
(Dick: Why not just have a series of cunningham holes put into the luff of the main, roll until you hit the one that suits the conditions, and then put a line through the grommet, around the mast and under the gooseneck to anchor the tack of the main?)

7. Rolling The Sail. Begin rolling by taking a small tuck of approximately 6" at the outboard end (clew) of the boom. This will keep the end of the boom from drooping too low. For a moderate reef, roll to the tip of the first batten. For a deep reef, roll to the tip of the second batten. Remove battens, don't roll them in, and watch out for fiberglass slivers on old battens!

8. Lashing. Tightly lash the sail to the boom at both ends. Tie the line for the “Chinese jibe” preventer to the boom vang. Note: Don't put the vang on too hard! The boom vang must remain slack (or lightly loaded) to prevent damaging the gooseneck.

9. Hoist sail. Replace the boom in the gooseneck and tie the cunnigham line to the pin attachment point so as to counter the twisting moment imparted by the sail. (This will, we hope, save the gooseneck from breakage!) Raise the sail. Take up slack in the boom vang.

10. Go Sailing!