Your mainsail is the workhorse of the sailing rig , therefore it tends to get the most use and abuse. Four leading sailmakers – Steve Cruse, a sales consultant with North Sails, Robbie Doyle, founder and president of Doyle Sails, Butch Ulmer, president of UK-Halsey Sails and Bob Pattison, co-owner and technical director of Neil Pryde Sails – were asked to explain what goes into the decision-making process when buying a new mainsail. Their opinions vary but their advice will no doubt help guide you when the time is right.
How can you tell when the time has come to replace your mainsail?
Steve Cruse: Every sailor has different needs and expectations for his mainsail. In general, a sail should be replaced when you are forced to make frequent repairs or when the draft of the sail has stretched so much that it is baggy, which results in reduced lift and increased weather helm.
Robbie Doyle: You should replace the main when you can't stand to look at it anymore. Racers will know it is time when they see performance suffer. Laminated sails will show signs of shrinkage at the leech and luff. Dacron sails will get baggy in the middle. And cruising sails will begin to wear out from use and UV damage.
Butch Ulmer: It all depends on how the boat is going to be used and where it is going next. If you sail the southern latitudes where UV is a problem as opposed to the northern regions, a sail will have a shorter lifespan and will have to be replaced more often. You can tell when it is time to replace the main when it has stretched out of shape. We have a downloadable program on our website that will analyze digital photos of your sail and rate its shape (see link).
Bob Pattison: When your repair cycle starts to increase you will know the sail is getting tired and needs to be replaced. You can also have a hard look at the sail when the wind is up in the 15-knot range. If there is a crease from the clew to the head at the inboard tips of the battens, then the sail has become baggy and the draft has moved aft to more than 50 percent of the boom's length.
For coastal and offshore cruising and rally sailing, what are the most essential qualities built into your new mainsail?
Steve Cruse: Offshore and rally sailors will need more durability and performance built into the mainsail than daysailers and coastal cruisers. That means either using a high end Dacron or going with a high quality laminated sail. In both cases, solid construction and UV protection are important qualities.
Robbie Doyle: The key element of a new mainsail is how well it fits your mast, boom and reefing systems. Even a well built offshore quality sail will not last long if it fits poorly. For the sailmaker, the measurements are critical as is knowing the boat and how it will be sailed. If you can't get a sailmaker onboard, take as many digital pictures of the sail as possible and take the old sail to your sailmaker.
Butch Ulmer: The force of the wind on sails varies with the square of the wind's increase in velocity so if the wind increases from 10 to 20 knots the force increases by a factor of four. For offshore sailors, who are likely to see stronger sustained winds, the mainsail has to be strong and durable. That means the sail cloth should be one or two ounces heavier than for coastal cruising.
Bob Pattison: You have to know how you are going to use your boat and where you will be sailing it. In the end, the key is the cloth you and your sailmaker choose for the sail. There are something like 500 different fabrics available to the sailmaker. I recommend that an offshore cruiser carry fewer high quality sails that are good through the widest possible wind conditions.
What type of sailcloth do you recommend for cruising?
Steve Cruse: We would look at the customer's needs first. In most cases the durability and lower cost of Dacron will be attractive. For boats over 40 feet, we often recommend higher-tech sails, such as a Spectra laminate, for this type of sailing since it holds its shape better than Dacron. If you choose to go with a Dacron sail we recommend using a higher-end cloth that has a tighter weave and is more resistant to stretch.
Robbie Doyle: For most cruisers Dacron will be the cloth of choice. There is a wide variety of cloths and price ranges. The more expensive square weave fabrics are durable and hold their shape well. Old fashioned tight weave fabrics also work well. If you are going offshore, spending a little more money on better cloth really adds to the sail's performance and durability. Laminated sails will help those who want better windward performance but they don't really make a difference sailing off the wind.
