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303® Products on Sail Cloth

Two 303® products provide UV protection.
- Benefits of Using 303® Products
- Which one should be used on sailcloth?
- How Often to Re-Apply?
- Any downsides?


Answer: 303® Fabric Guard is for textiles...fabrics, carpeting...synthetic and natural materials that are inherently absorbent. Generally speaking, synthetic textiles are various types of plastics, but plastics that are made to mimic the appearance, texture and absorbency of natural fibers.

303® Aerospace Protectant™ is for plastics, synthetic materials in an inherently repellent form.

Many plastics can be manufactured in both forms. One example is polyester. Polyester carpeting is polyester resin in a textile form....spill water or other liquid on it and it absorbs like cotton. Or in another form, polyester resin is the gelcoat fiberglass in your boat, jet ski or snowmobile, nothing at all like a textile, but hard & repellent to water. Acrylics, nylons, polypropylene and many other plastics in both forms are common components of innumerable consumer items. So whether 303® Aerospace Protectant™ or 303® Fabric Guard may be used depends primarily not on the type of plastic, but the form into which the plastic is made.

Are there any other benefits to using `303®' on sailcloth?

a) Dacron: 303® Aerospace Protectant™ will restore lost color to faded colored dacron, and periodic reapplications will keep it that way. 303®'s super-repellent finish minimizes the cutting action of mineral deposits and sand on the seam stitching and thereby prevents or dramatically delays seam failure caused by abrasion.

b) Monofilm: 303®'s super-smooth finish repels dirt, soiling and smudging. Treated monofilm cleans up much easier when soiled. And sand and dirt that would otherwise dig in and scratch monofilm is often repelled away instead so scratching is minimized. Perhaps most appreciated by windsurfers is it's superior and long lasting water-sheeting properties (for maximum water-sheeting, buff aggressively with a soft dry cloth).

Sailcloth: The three most common sailcloths are dacron (polyester), monofilm (polyester), and ripstop nylon.

Dacron: Bainbridge, headquarted in Canton, MA U.S.A, is the acknowledged world leading authority on sailcloth and one of the largest manufacturers. Bainbridge conducted UV screening tests on dacron sailcloth in the early 80's and have been selling it in their catalog for that purpose since 1986. Dacron sailcloth, though a woven material is polyester resin in a repellent form. Dacron sailcloth is typically the brightly colored sail material...red, green, blue, etc. Dacron sailcloth is typically treated at the factory with a finishing resin to produce the required degree of stiffness, known as "hand".

Monofilm: Monofilm sailcloth is not a woven material, but polyester resin in a solid, transparent form. Monofilm sailcloth is commonly used in windsurfing. The first company known to have tested 303® Aerospace Protectant™ on monofilm is Primex Marketing, a major wholesale supplier to the windsurfing and paddling aftermarkets. Since then a number of other companies have reported that 303® Aerospace Protectant™ is extremely effective on monofilm as well as dacron sailcloth.

Ripstop Nylon: Though it very well may be that 303® Aerospace Protectant's™ UV screening properties are effective on ripstop nylon (303® is effective on nylon in other forms), the company has received no reports of testing by any manufacturer. 

How do you apply 303® Aerospace Protectant™ to dacron & monofilm sailcloth and how often do you need to and how much does it take?

a) Apply 303® Aerospace Protectant™ by spraying on and wiping completely dry.

b) If maximum UV protection is desired, reapply 303® Aerospace Protectant™ every 30-45 days of EXPOSURE. Note: Sailcloth is not constant-exposure material. Dacron in five months of continuous exposure (summertime-Florida) will lose 85% of its tear-strength! Since sailcloth is usually only exposed when used, it may take a typical sailor one or more years to accumulate the equivalent of 30 days constant exposure. With colored dacron, a good way to tell if you've waited too long since the last treatment is to do an area. 303® Aerospace Protectant™ has intense color-restoring properties...so if you see any color come back at all, don't wait so long to reapply the next time. Reapplication intervals for monofilm is the same. Regular reapplications of 303® Protectant are inexpensive and will keep dacron and monofilm sailcloth looking and performing like new.

 c) Coverage on dacron is typically 140 sq. ft. per 8 oz bottle. Even better coverage on monofilm.

Are there any downsides to using 303® Aerospace Protectant™ on sailcloth?

303® Aerospace Protectant™ will soften some of the resin finish with which the Dacron is treated at the factory to give it stiffness. Some racers consider this a negative. Others report increased performance from 303® treated "softened" sails: 1) That with treated sails you can point several degrees higher into the wind and 2) That the reduced drag co-efficient of treated sailcloth adds measurable speed. 3) That sails are much easier to bring in and store at the end of the day.