Four Essential Sail Care Tips for Charterers | Modern Sailing

Four Essential Sail Care Tips for Charterers

San Francisco Bay’s famously strong winds are tough on sails, especially on boats that are sailed, raced, or chartered frequently. You can show your boat’s sails a little love and promote their longevity by following these four essential sail care tips.

As a bonus, you'll also learn a few sail trim tips and increase the overall enjoyment of the sailing experience for you and your crew!

Tip #1: Sail Care Begins and Ends at the Dock

Before leaving the dock, explore your boat's reefing system and be sure you and your crew understand how to operate it. If encountering a reefing system that you’re not familiar with, practice reefing at the dock with your crew. Practice promotes crew confidence and quick and efficient reefing, reducing the amount of time a sail will luff unnervingly during the reefing process.

If the wind is forecast to be greater than 15 knots, it a good idea to preset one or two reefs in the mainsail while at the dock. When the wind is anticipated to be less than 15 knots, ensure that the reef hook (if any) is unhooked at the reef cringle on the tack and all reefing lines are loose and free to run. This will allow the mainsail to be hoisted all the way up with no hitches from the reefing system.

Some mainsails, particularly those in our Silver Fleet, have buntlines in the mainsail (also known as reef ties) to secure the bundle of loose sail that hangs down below the reef point, known as the “bunt." When reefing, tie the buntlines together loosely with reef knots around the bunt. Pulling the buntlines together too tightly around the bunt can cause excess tension at the cringle where the buntline passes through each side of the sail, which can damage and eventually tear the sail. Also, while tying the buntlines around the boom may make help improve the shape of the reefed sail somewhat, it also increases stress on the sail. At Modern, we encourage recreational sailors to tie the buntlines around the bunt itself, not around the boom. This helps to increase the longevity of the sail and prevents tearing at the buntline cringles.

Also, check the jib cars and ensure that you and your crew know how to move them up and down the tracks. Some recreational sailors never adjust the jib cars when sailing, but they can be useful to improve sail trim and reduce excessive luffing. (You'll learn more about jib cars in Tip #4.)

If you have been sailing with a reef in the mainsail, be sure to remove the reef when you return to the dock. Loosen the reefing lines and tuck them between flakes, release the reefing hook from its cringle in the tack, and/or untie any buntlines before you replace the sail cover or zip up the stack pack. Undoing the reefs helps preserve the crispness of the sail.

Tip #2: Furl and Unfurl Jibs and Mainsails with Care

Maintaining control of sail control lines helps to minimize luffing during the furling and unfurling process and prevents lines and sheets from whipping around and becoming entangled.

While unfurling an in-mast furling mainsail, keep the sail under control by maintaining some tension on the inhaul line as the sail comes out. When furling, similarly maintain hand tension on the outhaul. Also, keep the boat pointed in irons, but pointed very slightly away from the wind so that wind flows across the starboard bow. For a detailed explanation of this, furling mainsail best practices, and tips to unjam a stuck sail, be sure to read our article The Ins and Outs of In-Mast Furling Mainsails.

Follow the same line handling practices with roller-furling jibs. Maintain light hand-tension on the furling line as the sail comes out, and keep a light hold on the jib sheet as the sail is being furled in. Also, it is recommended to be on a broad reach while furling the jib to reduce stress on the sail.

The halyard tension for sails with roller-furling systems has been preset and locked in place by the Modern fleet staff. Do not attempt to adjust the halyard tension. Locate the halyard clutches and inform your crew of the importance of leaving them untouched.

Never force a stuck sail by applying excessive force on a winch. When encountering resistance, always try to locate and resolve the source. If in doubt, contact the Modern Sailing office. 

What happens if a sail is damaged due to excessive force? See our article Oopes, Ouches, and Accidents: What Every MSC Charterer Needs to Know.

Tip #3: Keep the Mainsail Off the Spreaders and Shrouds

Be careful when sailing downwind to avoid allowing the mainsail to make contact with the spreaders and shrouds. Sometimes this is inevitable, especially with swept-back spreaders. Simply do your best to minimize the contact.

Tip #4: Avoid Unnecessary or Excessive Luffing while Sailing

When sailing, if the leech edge of the sail is luffing excessively despite best efforts to trim with the sheet, try tightening the leech line, a thin cord you'll find tucked into a pocket on the leech above the clew. (This can be challenging to accomplish when the sail is under a heavy load in strong wind or luffing in irons). For a luffing mainsail, you may also try increasing the outhaul tension and/or tighten the boom vang.

If a jib is luffing excessively, relocating the jib track cars can help. Adjusting a car forward increases the downward force on the clew, reduces twist, and while straightening the leech, also deepens the belly of the sail. This can be a useful adjustment when sailing on a close haul or reach. Adjusting the car aft will flatten the sail and increase twist. Also, when sailing on a close reach or close haul, adjust the track car forward. When sailing on a broad reach or run, adjust the jib car aft. Depending on your point of sail, generally, the car should be positioned such that the angle of the jib sheet points to the center of the jib's luff when sighting up from the car along the sheet.

To relocate a jib car, first, tack the boat to place the load on the opposite car. Adjust the car placement on the lazy sheet (windward side) and then return to your original tack. Do not attempt to move a leeward jib car when it is under load – to do so may result in injury.

Ready to learn more about jib car placement and other advanced sail trim techniques? Our Advanced Sail Trim Clinic will teach you advanced techniques to help you make the most of every sail - and be kind to the sails while you're at it.

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  • Rolf Zingg

    Since many, many years, I had the dream to sail underneath the Golden Gate bridge. On October 14th last year, my dream became true. Thanks to our dear friend Aaron Fritz who made it possible and organized this cruise for us. With this adventure I was able to achieve one more milestone on my sailing career.

    Finally on the water, it was great! Full moon made the flows even stronger and it was like sailing in a washing machine.

    I did my sailing education in the English Channel, where the situation with the wind and flows is comparable to the San Francisco Bay. So I felt pretty much "at home" being on the helm in the Bay.

    I hope our skipper Stan Lander enjoyed this day cruise too. We, definitely did! It was an unforgettable experience for all of us.

    A very big thank you to all of you who made it possible, that my dream became reality! Also thank you for the MSC flag I got at the end of the day. It found it's place in my study, where I can see it daily.

    Rolf Zingg
  • Esther C

    I took ASA 101 with them recently. They have the best customer service I've ever seen! I mistyped my address when I signed up online so didn't receive the textbook. I called and the lady immediately sent me another copy! Everyone at the club is super friendly.

  • John Clark

    Every aspect of Modern Sailing - training, syllabus, course materials, quality of the boats, quality of the instructors, and the very friendly and helpful staff - exceeded my expectations. Modern Sailing has a first class sailing program in an environment with challenging winds and currents. I look forward to coming back to charter a boat and certainly plan to continue my sailing training.

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