Sail care: how to look after your sails
How you look after your sails can make a big difference to their lifespan and your pocket.
June 3, 2021
Sails that are well cared for can last many times longer than those subjected to constant abuse and neglect. These are the 12 most important aspects of keeping sails in good condition:
Sail care: 12 top tips
- Minimise flogging at all costs, as this rapidly weakens the cloth.
- Adjust leech lines to stop the trailing edge of the sail vibrating or flapping, which can cause a lot of damage in a short time.
- Protect sails from the sun when they are not being used.
- Regularly check for damage to stitching and chafe damage in way of the spreaders, shrouds, guardrails, stanchions and so on.
- Periodically check the condition of the leech of each sail and the inner end of batten pockets.
- Reef when appropriate – carrying too much sail with stretch the cloth, while depowering in gusts will result in flogging the sail.
- Choose fully battened mainsails for cruising.
- Relax halyard and outhaul tension before you pack the boat up after sailing.
- Don’t motorsail for long periods with the mainsail flapping.
- Don’t leave sails stored for long periods with sharp creases, or place heavy items on top of sail bags.
- Don’t allow dirt to build up on sails that are left in place, such as roller furling headsails, as this rapidly accelerates the build up of mould.
- Get a sailmaker to check sails over at the end of the season, including professional laundering and drying.
Chafe and sun damage
Flogging and sun damage are by far the two biggest causes of damage to sails, and in many respects sail care involves a lot of common sense. While it’s inevitable that some flapping will occur when hoisting sail, reefing and tacking, the sail will last longer, and retain its designed shape for longer, if you can keep this to a minimum. Reef early, sheet sails on as soon as they are hoisted, and avoid motor sailing to windward with the mainsail flapping. The latter also burns extra fuel as the sail causes extra drag.
Sails are also vulnerable to chafe – self adhesive Dacron spreader patches positioned for each of the mainsail reef points are easy to apply and will repay their modest cost many times over. Equally, stitching can be damaged where genoas rub against shrouds or babystays.
Far too many sails have succumbed to an unnecessary early death through ultra-violet degradation. Never be tempted to skip putting the sail cover over the mainsail when the boat’s not under way, and with lazy bag systems make sure the bag is fully zipped over the sail at all times. Similarly, the sacrificial strip on furling genoas needs to be in good condition to protect the sail cloth. Don’t be tempted to postpone replacing the strip once it starts to degrade –this is invariably a false economy. Unpicking the old stitching is a labour intensive process, so around one third of the cost of the job can be saved by doing this element yourself. On an infrequently used boat you should budget to replace the UV strip at least once during the life of the sail.
Examine stitching on a regular basis – often this doesn’t last as long as the sail itself, thanks to unavoidable chafe on the seams and sun damage (the relatively fine twine used for the stitching is more susceptible to this than the thicker sail cloth). If stitching is nearing the end of its life it should be given attention at the first opportunity, otherwise in a strong wind a larger tear can be propagated. It’s very economic to get the high load and high wear areas of a sail restitched, so this is a worthwhile task that will significantly increase lifespan and reliability.
The leech is usually the most-highly loaded part of a sail and is also the part that is subject to the greatest amount of flogging. This is therefore invariably the part of the sail that fails first. Some heavy duty sails specified for ocean use have a two-ply leech, which doubles the strength in this area. Retrofitting a two-ply leech is often a viable way to extend the useful service life of an existing sail, providing the sail shape is still acceptable.
Testing the strength of sail cloth
There are two easy tests to check the intrinsic condition of a woven polyester (Dacron) sail. The first is whether it’s possible to separate the fibres with a thumbnail. The place this is most likely to happen is next to the leech line tabling, especially on a sail that has been subjected to a lot of fluttering due to insufficient leech line tension. If it’s possible to poke your thumbnail through the fabric, needless to say it’s severely weakened and in very bad shape. A more severe test is to put a large sailmaker’s needle into the sail and then attempt to drag that sideways through the material. If the sail is in good condition it will resist this pressure.
The failure mechanism for laminate sails tends to be a break down of the Mylar film, followed by flex damage to the structural fibres. Eventually these will break, indicating a severe weakening of the sail. The process can be slowed at an early stage by sticking self-adhesive Mylar over any damage to the film.
As well as examining the leech also look for damage on folds, especially with a sail that’s been stored for a long time, or regularly re-folded in the same place at the inboard end of short battens and in way of reef points and sail slides.
Find out more about sails in our features how to understand and buy sails, choosing the right sailcloth and sail coating and cleaning.