Sunday, September 8, 2019

UV Protection for Sails

Yup another Practical Sailor Teaser.

A year ago I began researching the use of paint for UV protection on roller furling jibs.

I started with test panels on the roof. House paint samples failed right away, either chipping or pealing in strips. But special purpose paints, compounds either for sails or cloth, generally held up pretty well.

Last week my primary jib basically died, with multiple (4) tears through the Kevlar leach. The only thing that kept it from spliting right across was the Sunbrella cover and strong repairs just forward. The foot also developed multiple smaller tears the same day. It was breezy.

Thus, it was time to install my back-up jib, which has only a failed UV Dacron cover.

  • Will the paint stay on? I painted it months ago, I've rolled it in and out a dozen times, and tacked dozens of times, though in moderate wind. So far, it looks and feels good.

Amazon MDR inflatable paint. Left over from the dinghy. It lasted ~ 5 years on an inflatable, with very little pealing, so why not? I'll report aback in a year or so. Sooner, if it fails... but I don't think it will.

Time will tell. I also have samples of painted cloth burning away on the roof. I'm thinking I'm going to leave them until next Fall, and then make them into flags and drive around for a few days, giving them a severe flutter test.

I'm also going to get some quotes on a new jib. Even if the paint does fine, this one is long in the tooth and I don't trust it. I'm about done with laminates for furlers. It's a bad marriage. I'm going with polyester next time. 

I still like a Mylar main. It lives under a cover and does not flog (full battens). Yet both of them (I have two sails of indeterminate age) developed tears along the bolt rope, because the cloth does flex there. Compared to the leach, of course, this is a non-structural area, and is far easier to repair. And unlike polyester, they don't stretch, at all. When it comes to square top sails, that's a big deal.

1 comment:

  1. (From a reader, abrievieated)
    Your post on painting sails for added UV resistance reminded me of a post
    on the Junk Rig Association page forum...

    "... Now for some interesting innovations that we are considering. Andrew has
    successfully painted polyester sails increasing their UV resistance and
    strengthening the fabric. The paint used in a high quality Acrylic Latex
    House Paint cut by half with water. The paint is applied with a roller.
    There is some minor flaking but this is minimal and decreases with further
    applications. A small price to pay for added sail life. This innovation is
    high on our list. We will let the sails weather a bit then add the paint to
    change the colour from basic white. Acrylic Latex House paint has served us
    well on the decks and hull of Easy Go...."