Here is the line up of household chemicals I used for sail cleaning. Borax and OxiClean are common laundry detergents that can be safely used on sail cloth. Tilex contains chlorine bleach and should not be used on sails, but in the case of stubborn mold or mildew stains minimal use will help to remove the stains, but must be washed completely off very soon or it will damage the stitching and possibly the sail fabric as well. A hand scrub brush and knee pad are very useful as well.
To start the process, the sails are first soaked in a large container (I used a big garbage can) filled with Borax detergent and water. I used about 1 scoop per 10 gallons of water, mixed until crystals dissolved, then immersed sail completely. This is allowed to soak for at least 24 hours.
After soaking, the sail is laid on plastic ground cover and Tilex is used sparingly with light brushing to remove stubborn stains. When the stains are removed, or no further progress is noticed, copious amounts of water from a garden hose rinse off the remaining Tilex cleaner. It is very important to remove all the chlorine bleach.
About 1 scoop of OxiClean is mixed with 10 gallons water in the sail bath and it is poured onto the sail and brushed over the entire surface. When working outside, the sail must be kept wet during this cleaning process so as not to “set” the stains. I progress through one side of the sale by unfolding portions onto the plastic ground cover, do a section then repeat on a new section. When that side is completely done, I turn the sail over and repeat the process until all the second side is clean. Not the sail can be folded then rolled small enough to fit into your sail bath container… in my case a large clean trash can.
The can is filled with the solution of OxiClean and allowed to soak for another 24 to 36 hours. After this second soak, the sail can be unrolled on the clean ground cover again and completely rinsed off with fresh water. The sail must be hung to dry. My sail maker suggested using the product “Force Field” UV Protection to coat the thoroughly dried sails. I am told it is available at Lowe’s hardware. This protects the sails from water and sun and prevents mold and mildew. I shall try it!