Not so long ago the only option available for repairing sail damage was by sewing. Therefore, problems encountered at sea on a long passage, or even when day sailing in remote areas often resulted in hours of torturous hand stitching.
Even equipping a cruising yacht with a small sewing machine was no guarantee of an easy repair – trying to manhandle the sail in the confined saloon of most yachts is next to impossible. And buying a bigger boat, with a larger saloon, just means even bigger sails to deal with.
However, in the past few years two crucial elements have changed. Firstly, all but the very lowest quality of cruising specification sails stretch much less than in the past. Secondly, the effectiveness of adhesives has improved enormously. Gluing patches to damaged sails has therefore become a viable option. The possibility of easy sail repairs also offers an incentive to lower the sail at the first sign of any problems, rather than continuing to port in the hope that you will arrive before the sail suffers catastrophic damage.
While conditions on board aren’t likely to be ideal for this, acetone can be used to dry and degrease the surface even in poor weather (although it’s worth checking with your sail maker in advance if this might damage the fabric or glues used in the construction of the sail). Ideally, you should try to place the damaged area on a flat surface such as the deck or coachroof. However, if that’s not feasible, it may be possible to place a chopping board, washboard, or locker lid beneath the sail to support it.
Before applying any patches round off their corners – this helps to avoid high point loads, reducing the tendency of the patch to lift. If possible, apply two patches each side, the first one around 30mm larger than the damaged area. Ideally the second patch should be significantly larger – that way, if it starts to peel before you can make a professional repair it’s not an immediate problem. If time permits it’s worth putting a few stitches on the corners, to help secure them.
Sailmakers can supply excellent repair kits with self adhesive patches that suit your sail cloth – these are significantly better than those sold in chandlery stores. If you don’t have sufficient self-adhesive material, Dr Sails is a first-rate adhesive that’s designed for the purpose and has been tested in the gruelling conditions of the Volvo Ocean Race. A more rough and ready alternative is a PU adhesive sealant such as Sikaflex 291. While this will not make a repair that’s as neat, if applied to the patch with a notched spreader it will provide excellent adhesion, especially once fully cured 24 hours after application.