I hope some people chime in here with their personal experiences. I have read a number of opinions on this board which seem to express the belief that polyethylene kayaks and/or Royalex canoes have a finite life time after which the plastic material becomes brittle to the point that it will inevitably crack when used for whitewater river running.
While it is certainly true that boats submitted to continuous UV exposure age rapidly and become brittle, my experience has been that poly or Royalex boats properly stored have a long, if not indefinite life span. I have boats more than 15 years old which seem fine, and I have seen old Perception Dancers and Mirages on the river without visible cracks.
What has been your experience? Have you actually had boats more than 5 years old crack easily, assuming they were properly stored, keeping in mind even a brand new boat can be cracked.
I had one poly boat crack after only
five years. That was back in the mid 80s, and the manufacturer, Perception, told me that, at that time, 5-7 years was about the average life under hard use. I have a Perception Corsica, bought in '93, that is still OK, but at its age, I would not trust it on a hard run away from the road.
My personal observations on old ABS boats are limited to a Mad River ME, over 15 years old at the time, that got loose from its owner, careened down a steep slope, and ran into a tree. The boat was almost empty of added weight. Air temperature was already in the upper 40s. Normally I would have expected the bow to fold and crumple somewhat, the typical result when an ABS boat runs stem-on into a rock. Instead the end of the boat split open in a jagged fashion strongly suggesting brittle plastic. After a ton of duct tape, it completed the run.
I think one might use an ABS boat on lakes or easy rivers almost indefinitely, but I would NOT trust an old ABS boat to shrug off the same punishment sustained easily by a boat in its first ten years of life.
And one more point. ABS is protected
by its vinyl skin, so that sun exposure really is not an issue. Keeping it in the garage will protect a Royalex boat from temperature extremes, and may help the vinyl skin last a little longer, but in my experience, the vinyl wears off long before the sun gets it. As long as the vinyl is intact, using 303 is of mere cosmetic value. There is a reason that so many outdoor goods are made of vinyl plastic.
4 royalex canoes
all stored outdoors, under a deck, ranging in age from 7-approx.18 years old, are still doing okay. I paint them with Krylon Fusion which gets scraped off, and have epoxy smeared on the bottom of the Whitesell, but no external cracks or leaks…for the time being anyway 