More UV questions ?

Replies to other UV thread got me thinking …

Should I 303 the inside of my carbon & Kevlar hulls ? From feedback (& experience) Kevlar seems to much more susceptible to UV damage than C-F, Correct ?

Will Rx benefit from 303 ? We’ll be again taking our used hard Penobscot to FL for 2-3 months this Winter. I’ve installed skidplates but have worn thru the outer layer in a narrow area that extends full length of hull. This is only canoe for which I have no cover. When not in water it’ll sit on racks exposed to full strength of FL sun. To protect hull & especially exposed area should I consider paint (what kind?) or is 303 sufficient ?


ABS layer
Glen, I also have a Royalex OT Penobscot that has had a lot of use over its 18 year life. When ABS layer is exposed, UV will pretty quickly cause embrittlement (it gets much harder and less able to flex when stressed). Look closely at the exposed areas and chances are that you’ll see tiny parallel cracks. Best to paint it, or use some type of covering to shade the boat in storage. I’m suspicious of 303-like products’ effectiveness. I’m in the middle of some tests that I’ve devised that should put that whole issue to rest, at least for me. Will post results with pictures in a couple of weeks.

I would use Fusion or any other Krylon
spray paint and run a swath down over the exposed ABS. Do spot renewal when it gets scraped off in place. As previous post pointed out, ABS is unusually susceptible to UV damage.

However, the vinyl skin on ABS is fairly resistant to UV damage. The only consequence of long exposure seems to be chalky surface and dulling of color. The only time I bother with 303 or similar products on Royalex is when I am on a long western trip where the boat is in the sun all the time.

I would certainly be interested in any objective tests of 303 resistance to being washed off in water. I have seen some pattern effects on my boats suggesting that some 303 may survive a single river trip. Data on further persistence is hard to find.

We take our two QCC’s and our Jensen
ultralight kevlar canoe down to Florida for three months each winter and just use 303 on them.

Between use, they just sit on the truck roof in the sun.

They still look in good shape.

I do more damage to the bottom of the canoe in shallow water than the UV rays do.