We are probably heading toward a lighter canoe for rocky whitewater and whitewater tripping. So we are looking at high durability composite canoes. Something that might survive a wrap would be good for the worst case scenario. Nova Craft has a video on youtube of very serious on water testing for Tuff-stuff including broadside bashing to the chines, and wrapping. The boat is unbroken but the foam core seems to be rippled and then broken at midships. Does anyone have experience with Clipper Duraflex, or Swift Exped Kevlar involving serious bashing, swamped rolls through the boulders, or wrapping?
No experience with Clipper, but their
combo of vinylester resin and polyester cloth produces an unusually strong resin-to=cloth bond. My old Noah kayak has a similar deck construction, and when I enlarged the cockpit, I tried bending cut pieces of the laminate. I found I could bend them double and they would not split or delaminate. Vladimir Vanha of Noah used to do that folding trick when he discovered the merits of vinylester resin and polyester cloth, or CAP as he called it.
The bond is terrific, but the limit is the polyester cloth, which has much less strength in tension than Kevlar. Kevlar, however, bonds much less well with vinylester resin. A strategy would be to use glass for outer layers, polyester in between, and Kevlar inside.
But I don’t recommend wrapping boats. Better to have them blocked and bagged so they can’t be wrapped.
Clipper Kevlar Duraflex
I have a Clipper Kevlar/Duraflex Viper 12 solo whitewater canoe. I have not wrapped it, but I have come down very hard onto some rocks from off of 5-6 foot drops a couple of times as well as unintentionally boofing off of some sharp rocks.
The only damage it has sustained is some cuts through the gel coat, the deepest of which just penetrated a few fibers of the outermost layer of S 'glass.
The boat is very tough. This is a heavy layup using up to 10 layers of cloth on the hull bottom and a minimum of four layers on the upper sidewalls. It is not light. In fact, it is as heavy, or possibly a couple of pounds heavier than the Royalex version of the same boat that used to be made by Mohawk.
The boat can be made lighter. It comes with aluminum gunwales and I specified the heavier of two different gauges of gunwale as well as vinyl gunwale covers. It is also gel-coated. A non-gel coated boat with the lighter weight gunwales would probably have been a couple of pounds lighter than the Royalex version.
Here is a thread in which a few owners of Clipper Duraflex Vipers offer feedback:
I would avoid any boat with a foam core or ribs for whitewater general river running.
blocked? please explain
Internal foam reinforcement of hull &
thwarts. In the olden days we usedd giant float blocks.
probably preaching to the choir
but i think the biggest issue is how much flotation you put in the boat. You can pretty much destroy anything without flotation regardless of what it is made out of. Having Paddled a few boats that have been wrapped, I can tell you that it wasn’t a lot of fun and can get expensive.
My two cents- flotation, flotation, flotation.
Ahh but part of the thrill is running stuff when it counts the most, like a wilderness canoe trip with all the gear tied in. Sometime you win and sometimes you lose.
“Serious” ww canoes are stuffed to the gills with flotation- I’ve paddled aluminum, abs, poly, twintex canoes. Poly, fiberglass, kevlar kayaks. the key with all of it is good flotation (firmly secured air bags).
Lets concentrate on that wilderness river trip with a boat full of gear and a few hundred pounds of water. A place where royalex has risen to the top for good reason. Thanks
I think you roll the dice
in that situation regardless of what the canoe is made out of. Believe it or not there wasn’t that much difference paddling a wrapped OT tripper or an alumacraft (or grumman) despite some heavy duty advertising to the contrary. In the tripper you got this big wrap line, often with the top layer broken through. It sort of popped back but with a big crease that never goes away. With the alumacraft the whole thing gets kind of twisted on its center axis with the ribs popping up. But with the alumacraft you could stomped the shape back out by putting the canoe in the water, and stomping and kicking. Then you put chewing gum in the holes where the rivets popped out from the hull to the ribs Both paddled like “pigs” afterwards. Aluminum grabbed the rocks more and not so much fun in the rock gardens in general but in a true wrap scenario the abs and aluminum both suck pretty equally. Sharp edges are a reality for an aluminum boat or any boat aluminum gunnels, and even vinyl gunnels that hide aluminum on the inside.
As far as hull shape- I’d avoid anything with a flat bottom.
If your really going to wrap or pin a boat- poly would be my first choice- heavy as it is. Definitely some design limitations (not so good for tandem tripping canoes).
kayaks seem to fair better after a good pinning. They don’t actually wrap as much as just get lodged down between the rocks, though often below the surface. Poly works well in that situation when you can lift one end of the boat out with it full of water. Glass wouldn’t handle that so much.
The magic material is air, getting the boat to float high.
My madriver flashback in abs didn’t really float or sink- somewhere in between, when full of water- so you had to rely on air bags.
If you are concerned about a
possible wrap on a true wilderness trip maybe its time to carry? No matter what boat you have, even royalex, a bad wrap can be fatal to the hull as far as field repairs anyway.
And before you can even think about repairing the hull, you have to get the boat unpinned. That can be difficult on a wilderness trip with limited resources. I wrapped my tandem boat in a relatively modest rapid, and it took 4 of us over 3 hours to get it unpinned.
This was a Royalex boat, so once it was unpinned it only took one foot stomp to pop it back into shape. Safe money says go for a light boat and carry the rapids.
hey eck, how does the boat
paddle now? That's a pretty good broach. Could you stand up on the downstream side of the boat, in the eddy created by the boat? Could or did you try lifting the end upward that is closest to the shoreline?
Boat paddles fine now
There are a couple of creases in the Royalex, and the gunwales are a little bent, but one foot stomp and it pretty much popped back into shape. I use it for poling and I’ve done some tandem paddling in it.
We could definitely stand in the eddy on the downstream side of the boat. I don’t think the water there was much above our knees.
Too bad you weren’t there tdaniel, because lifting the end near the shore is how we finally got the boat free. First we hooked up the z-drag and tried pulling - no way. Then we used the z-drag to try to roll the boat forward - even less likely. Finally we found a log and slowly pulled the z-drag while prying up the end near the shore with the log. Once we got that end out of the water the current did the rest of the work pulling the canoe of the rocks.
It’s my own fault that the boat got wrapped. The boat had end bags, but one of them had a leak and was flat when the boat got pinned.