Reefing Right: Tips from the experts

Sailing in big breeze can be many things, fun, exciting, maybe even stressful and sometimes expensive when things go south.

Last year’s Rolex Sydney Hobart Yacht Race saw many teams face retirement when they suffered sail damage on the first evening’s southerly change. Shortening sail quickly and easily when the breeze comes on is key to looking after your sail.

There are many different reefing practices for the mainsail. Most systems are either predetermined by the mast manufacturer or customised by the crew to best suit how they perceive the fastest and safest way to reef the sail.

The process of reefing needs to be both safe for the crew and fast to limit the amount of time the sail is flogging as reefing is high risk time for the sail damage. The best way to achieve this safety and speed is practise, practise, practise, both at the dock to get all the lines knots and clips positioned correctly and on the water with the whole crew.

Try reefing first in easy conditions where time can be taken to go through the process and then in anger to check everything under load. This is also a great time to get marks on the halyard so you know where to drop the sail too, get the luff on the reef horn or clip and measure out the reef ties for tying up the reefed section of the mainsail. Also check the mainsail has the spreader chafe dots fitted in the correct place. All this is great to see and do together for the whole crew, as the next time you do it will be under pressure and no doubt dark and windy! You can even go as far as taking photos to assist getting the boat set-up quickly and correctly the next time you go offshore.

There are many different systems for reefing the mainsail these days with furling booms, in-mast furling, single-line reefing, halyard locks and boom locks. Each has its place and benefit in the sailing world, but we will concentrate on the most common system known as slab reefing. This is the way that 90% of boats reef and is probably the most simple and reliable system when done correctly.

Put simply slab reefing is the process which involves getting the luff end secured and then winding in the outboard end in until the sail meets the boom and is nice and flat along the foot.

Let’s separate the two components that hold the reef in place as the forward end or luff end and the outboard or leech end. The following will best describe the majority of boats but for finer details or a check of your set-up if you are not 100% sure contact your sail-maker or rigger.



The luff end of the mainsail slab reefing system consists of reefing horns, a cunningham hook or a luff-line, these are the boat specific part of the luff end. The other is the sail part consisting of webbing loops, floppy rings or press rings. Whatever systems you have on the mast must match the sail so they work together to hold the luff end secure. With any of these systems or fittings, the most important thing to remember is to make sure the luff is held forward to keep the load off the boltrope or the slide above the reef tack, if the tack drifts too far aft the sail can pull out of the track or tear the sail.



The important thing to get right here is the position of the knot or the reef nappy along the boom in relation to the where the reef clew will land when the reef is in. Ideally have the line around the boom 50mm behind the ring in the sail when it is fully tensioned (see figure 4). This helps keep the sail up close to the boom when the sail is sheeted on. Too far forward and the sail can not be flattened out properly.



The reefing process itself needs to be performed in an order of sequence. Once the call is made to reef the mainsail, everyone needs to fall into place by his or her normal crewing positions, ie mast and forward hand, pit and pit assist, mainsheet trimmer.

  • Run main halyard to ensure no twists or knots, a twist or knot in the halyard during the drop only increases the flogging time. Load halyard on winch.

  • Load up the outboard end reef line, check all is clear at the leech end.

  • Ease vang off completely and outhaul off a few inches to relax foot.

  • Mainsheet trimmer over sees and communicates the whole process.

  • Mainsheet eases the mainsheet and calls “Drop halyard”

  • Mast pulls down the luff and connects the sail onto the horn or C/Ham clip

  • Mast ensures the C/Ham is max on, calls made and signals to the pit to go hoist on the main halyard, watches boltrope feeding into the rig without snagging.

  • Pit raises the halyard until the luff is firm, signals for the pit assist to start grinding the reef line in.

  • Mainsheet trimmer watches and calls the reef line left to grind in and makes sure the reef line is not crushing the sail. The sail can be pushed out to leeward or pulled over to windward, depending on the way the reef line is run or what tack you happen to be on. Remember we are winding the boom up to the sail, not sheeting on the sail with the reef line, so make sure the mainsheet and vang are eased.

  • Mainsheet makes call on the reef line and sheets on the sail.

  • Mast and forward hand secure the reefed section of the sail around the sail through the reef eyelets across the foot, ensure you only tie around the sail and not the boom also. If the reef line breaks this will avoid the sail tearing at the reef tie.

  • Mainsheet checks leech line tension VIP. Splits in the leech are where the tears usually start during reefing often caused by lack of attention of the leech line

Some important things to remember when reefing;

  1. Good clear communication, jacket hoods down in any manoeuvre is a good rule.

    1. If it’s dark, make sure the mainsheet trimmer has a torch so he can watch the part of the sail being winched to ensure there is no tangle or over tensioning.

As with anything in sailing, practice and good equipment is key to the success.

Remember to finish first, first you have to finish. So look after your sails!

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