Dealing with Dirty Sails

Posted by Darrell Nicholson at 04:44PM - Comments: (6)

Attack mildew stains early. Once they have spread into the fibers, getting rid of the stain is unlikely.

Among the many chores we’ve got ahead of us this winter, removing, and storing sails is one of them. This is also a good time to clean the sails.

We published a PS Advisor on the topic of cleaning sails in the April 2002 issue. Here’s a recap of that report and other articles we’ve done in the past.

You can clean most sails yourself, but be sure to set aside enough time. You also will need a large work area.

Be aware that some sailcloth materials (Kevlar and nylon in particular) are sensitive to certain substances—chlorine bleach and acetone, to name those most damaging. While Dacron holds up to mild doses of bleach, spinnakers and light-air sails made of nylon are particularly vulnerable. If you expose Kevlar or nylon to bleach—say you decide to rinse the sails in a swimming pool—they can lose up to 90 percent of their original strength.

For washing your sails, most sailmakers recommend using mild soap and water, and avoiding anything abrasive. Use a soft brush, if necessary, to loosen dirt. For dirt or stains that are more deeply embedded, you may need to soak the sail, so you'll have to locate some kind of large container, depending upon the size of the soiled area. (This is the time to requisition your kids' inflatable swimming pool.)

For mildew, some sailmakers advise simple household bleach, a 5.25-percent solution of sodium hypochlorite. We'd use a highly diluted blend first. Be sure to rinse thoroughly. We had mixed results with various mildew removers on sails in our 2009 test of mildew removers.

When you've finished cleaning, always rinse the sail liberally with fresh water. And, if you hang your sails to dry, do so at a time when it's not windy. If a sail is left to flog or flutter, you can do more harm than good. Remember, sails are composed of fibers, and the more back and forth bending those fibers have to endure, the more quickly they'll lose their strength.

You'll find additional information about the care and cleaning of sails on the North Sails website. Almost any large sail loft with a service department as most have arrangements with specialty cleaning services.

Comments (6)

Prevention is the cure. Obviously, keeping sails dry will do it, but since that's not always going to happen, consider preventative treatments such as those often used by garment manufactures for odor control; quatrenary silicone amines.

In the September Practical Sailor, "Fighting Mold, Mildew, and Lichen," several effective, fabric-safe preventative treatments were tested. Use them in the final rinse or just spray them on, and let dry. Do not exceed the recommended dose, it won't help. For a cheaper solution, use one of the closely related swimming pool algae control products. Perhaps this is part of why those suggesting pool cleaning get good results; the final rinse is the pool water.

As for stains, I'm with the sailmaker; just a little gentle cleaning. If that doesn't do it, I don't mind stains.

Posted by: Drew Frye | December 7, 2016 10:37 PM    Report this comment

The first requirement when cleaning/soaking sails is to have a container large enough for the sail...bigger boat = bigger sails = bigger container. Do you or one of your friends own a pickup truck...problem solved. Line the bed with one of those cheap blue tarps and fill it full of warm water, add soap, etc., stir with a paddle/oar, put in the sail, stir some more and let it soak overnight. Rinsing and drying is the next challenge easily solved if you have a large tree nearby to which you raise it with a block and tackle you got from your boat. Siphon the water out of the truck bed with a garden hose as the sail dries, DO NOT open the tailgate. I've done it and it works great.

~ ~ _/) ~ ~ Mike

Posted by: MJH | December 7, 2016 12:08 PM    Report this comment

One of the easiest ways to clean Dacron sails is to toss them in the pool, 4 or 5 hours after shocking. Tie them off, so they can't get sucked into the filter system, and let them soak for a few hours. The water circulation is all that is needed for mechanical agitation, and is very gentle on the sails. Haul them out, rinse them off with freshwater, and hang them until just dry (in very light wind). Nice clean sails, with little effort, or risk of damage.

Sheen Marine

Posted by: Oh for | December 7, 2016 9:59 AM    Report this comment

I had good results soaking sails in a large plastic garbage can with warm/hot water, laundry detergent, and oxi-clean.

Posted by: Unknown | October 26, 2013 11:07 AM    Report this comment

A practical and inexpensive process is to wash sails on a windless day in the early fall . . . I hoist my mainsail at the dock using a fresh water hose. Start with the sail flaked on the cabin top under the boom, then raise the sail five feet at a time washing both sides of the sail - soft brush and mild soap and a good rinse. As the upper part of the sail is washed, soapy water drops on to the flaked sail helping to loosen the imbedded salt on the lower part of the sail. When done, leave the sail up to dry then flake it on the boom where it belongs until the boat is put away for the season.

This can be done solo - but make sure there is little to no wind!

Posted by: Unknown | October 8, 2011 6:01 AM    Report this comment

I am hesitant to recommend bleach to our clients. I would rather see a stain on a sail than have a weakened sail. I've seen sails damaged in an overzealous effort to clean them. In many cases the issue is solely cosmetic.
Since it's fall, many PS readers will be putting boats up for winter. Inevitably some will decide to order new sails over the winter months. If the boat is being stored with the mast removed, be sure and measure the rig before putting the boat away for winter. Every year we have some very disappointed people when we inform them that we need measurements taken with the rig up.

Posted by: DAVID B | October 5, 2011 5:29 PM    Report this comment

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