Modern 'Glass Boats: Can't Take A Punch?

Our '73 Moore has “octometric” layup,

– Last Updated: Dec-17-12 6:39 PM EST –

by which they meant that some layers were at 45 degrees. Whitewater layup experts don't seem to do that, but in shorter ww canoes and kayaks, subsequent layers are unlikely to have fiber orientation absolutely parallel to earlier layers. In examining broken composite boats, I haven't seen clear evidence of breaking along the line of cloth fibers.

Glass mat is ok for sea kayaks, because their hulls are not likely to be deformed as severely as ww kayaks. But I don't know of any ww composite boat builders over the last several decades who have incorporated glass mat. That speaks for itself. It might be used to stiffen ww canoe bottoms, but Kaz of Millbrook uses Spheretex instead, which is a cloth infiltrated with tiny polyester bubbles.

Glass mat is typically coated with a substance to which epoxy does not adhere well. Those building or patching with glass mat should use vinylester instead.

I Agree

– Last Updated: Dec-17-12 6:58 PM EST –

For me, a light weight kayak is not about going fast. It's about lugging the thing around. Yeah, I chuckle at the folks who whine about lifting their boats to the top of their vehicles. If your boat is long enough and your vehicle is low enough you just lift ONE END AT A TIME. Not hard at all. Toting the damn thing to the water and back into storage is where the filthy language starts... and a cart is just more STUFF. No, it may not make total sense, but we old folks with money and way closer to the grave than the crib will pay the $ to make life a bit easier.

Yes, the light weight bike frame means a whole lot less for flatlanders and lots of them probably don't realize it. Here in piedmont, NC you are always going up and down. A short trip to the west and you're climbing frickin' mountains. The weight savings matters here.

It may not be all logical and sensible but I think the sea kayak market will want lighter boats. I don't know nothin' about the whitewater crowd.

Glass mat
has glue which dissolves in traditional resins. West says it’s OK to use their epoxy, but admit that the bonding chemical is not dissolved. Patching to old mat should be fine though, because all the glue would have been dissolved already.

Other than dedicated surf kayaks (like Mega) I didn’t know any WW boats were composite. I had assumed they were all poly. I would have thought sea kayaks distort more than WW boats. With their length, sea kayaks essentially have a longer lever arm. I’ve certainly felt mine distort dropping off surf waves or running over rocks. But I suppose they generally take much less impact damage than a WW kayak (I really don’t know, never been WW kayaking).

First, all ww slalom and downriver
canoes and kayaks are composite, for lightness. And there are certain special layups that are nearly as durable as poly, and more repairable, but such boats are about as heavy as poly. Usually such boats are made of some very stretchy fabric, in multiple layers, bound by a resin that forms an unusually tenacious bond to the fibers. An example was the “Fiberlastic” layup that Phoenix used to offer. Vinylester resin, and many layers of some kind of stretchy cloth. I own one such, and in 15 years of harsh ww campaigning, it only partly broke once, in a very small area.

I have two Millbrook ww composite boats, SS/KK with vinylester resin. They do break, but the layup would match the best composite sea kayak layups. Repairs are easy and straightforward. I have a Dagger slalom c-1, experimental S-glass outside, carbon inside, extremely stiff, but probably more susceptible to catastrophic breakage than an SS/KK layup. Heat cured epoxy.

I’m sometimes surprised by the lack of unanimity among composite boat builders. Maybe there’s a tendency to try to be different for marketing reasons. Some builders like to use only Kevlar, or to put Kevlar outside and reinforce with carbon inside. Not rational, though with enough layers or foam core reinforcement, you can get away with it.

three layers
still only three layers…just sayin

I don’t think your info is accurate
For example, my Kevlar/Duraflex Clipper Viper has 10 layers of cloth on the hull bottom and 4 on the sides near the gunwales.

It’s not that simple
Safety is only a concern with CF in the event of crashes or other impacts that cause frame damage. Up to the point of failure, it’s every bit as safe as any other material. Advances in resins, nanoparticles and combining CF with other fibers have improved durability substantially, and it will continue to improve over time.

I’ve got carbon forks that have been ridden for over 10 years without a problem, so even older CF technology was safe. The difference is that an impact that would bend a metal fork or frame will crack or break CF. That doesn’t mean that you won’t crash on a bent metal frame, so the actual difference in rider safety is debatable. In normal use, CF is perfectly safe and it’s not going to spontaneously fail.

It’s not all about weight, either. Although CF can obviously be fashioned into lighter frames than other materials, the real beauty of it is the ability to customize the stiffness to a degree that isn’t possible with metals. That’s been the biggest breakthrough in CF frames recently. Not only can the stiffness be tailored in location and direction, the layup can be fine-tuned for every frame size. Changing the layup using the same mold can produce very different frames, both in ride characteristics and price.

Custom frames are not only available in metals, either. There are several companies that build custom CF frames. You can have the performance of CF WITH a custom fit.

No, composites aren’t perfect, nor are they ideal for all applications. However, composites have yet to reach their full potential. Like it or not, the future for metal frames is going to consist of the low end of the market, plus small niches in other market segments. Ultimately, the future belongs to composites, which will continue to redefine performance and expand their market share as costs drop.

great to now have three boats over 4 layers. thanks

To the future, then
As it happens, I agree with you on the future of CF and similar materials. There will be so much more they can do and do it better in our lifetimes. There already is!

However, I stand by my statement that CF is not magically superior to other materials. As with any material, it depends upon how it’s deployed.

And new materials do not always totally or permanently replace old ones. There are bikes made of bamboo and I’m told they work pretty well. That’s something I’d rather hang on my wall, though.

Over the past 26 years I’ve evaluated lots of bikes. I’ll stick with my old steel Bridgestone MB for now, thank you. Nothing in aluminum ever felt to my taste. Ti was wonderful always, but unaffordable. My friend’s CF road bike was a revelation as how good it felt - light, absorbent, stiff where desired - but that fork warning label and some horror stories and the price keep me away from CF. MTBF is more telling than YMMV… LOL

I’m not sure where you get info about
the number of cloth layers in composite boats. I’ve owned a number of composite boats built by Phoenix, Dagger, Millbrook, Moore, Mad River, and Bluewater, and the minimum number of layers has been four. My latest Millbrook does appear to have only three layers in the upper sides, but the chines and bottom have two outer layers of S-glass, a layer of denser-than-usual Spheretex, and one to two layers of Kevlar. My Dagger, a 21 pound slalom c-1, has two S-glass outer layers, and two carbon inner layers.

I find it very hard to get specifics from some canoe makers about layup. You must have some special source of intelligence. When I have done repairs, I have not encountered three layer layup in those areas that actually break. Woops, one exception. Slalom kayaks may have a foam core deck where the only cloth layers are inner and outer Kevlar.

Take horror stories with a grain of salt
If someone claims they were just riding along (known in the bike biz as the “JRA” excuse) and they carbon fiber frame, fork or whatever failed, it’s probably a load of crap. While there have been some issues with off-brand Chinese bikes that you see on Ebay and Alibaba, there have been very few issues with bikes from reputable companies, as their designs are heavily tested and even the lightest ones are designed to handle exceptional stresses. CF bikes and components only fail if they’re damaged in some way and that doesn’t just happen by itself.

Frankly, compared to the other risks one faces on the road or trail, the risk of a CF bike failure is inconsequential.

The one exception in my opinion is CF seatposts for off-road use. I have seen them break and even though it wasn’t the horrific failure you might imagine (the post just bent backward, then sprung back once unweighted), it just doesn’t seem like a good application for CF. I have and do use carbon seatposts on the road with no issues.

Warning labels are there for legal protection of the manufacturer and are simply the result of our ridiculously litigious society. It’s the same reason that forks all have those ridiculous “lawyer lips” on the dropouts that effectively negates the function of quick release skewers. I remove the labels and lips from all of my bikes, I’m confident that I don’t need either.

Give me plastic and a cart
Maybe it’s just that all the rocks around me are sharp. Combine that with a lot of oyster beds and I want something really tough and abrasion resistant.

I’m pretty tired of patching my Kevlar boat. It doesn’t weigh a whole lot less than a plastic boat of the same size but it is a lot easier to damage.

At this point the only composite boat I’d like is a Kruger.