canoehead & HYBES
Thanks, mr canoehead. I appreciate your comments.
HYBES - Please explain/define “kevlar didn’t hold up” and also specify the boat maker and model. I sure am always interested in knowing other’s real life experiences - which is the whole reason I began this thread.
Again, thanks to all - y’all are a great bunch!
Abrasion
Abrasion and wear is the trouble I had with a kevlar Wenonah Sundowner. I’m much more satisfied with Souris River in Duralite w/keelgaurds now.
I believe Wenonah is one of the few
manufacturers still using Kevlar as an outside cloth layer. This, in spite of the fact that the outside layer sustains both abrasion and, predominantly, compression forces when struck. Kevlar is amazing as an inside tension layer, but is mediocre or worse as an outside layer where compression forces predominate.
If Wenonah used even a single layer of E-glass, or better yet, the stronger and harder S-glass, on the outside, their boats would not fuzz, and their boats would be stiffer.
Most manufacturers of “Kevlar” boats, including most builders of whitewater “Kevlar” boats, use one or two layers of glass for the outer layers, and use Kevlar only for inside layers to prevent catastrophic propagation of splitting. Wenonah goes their own way. They make very, very good boat, but their boats would be better if they accepted common knowledge.
Does glass cloth come in that …
…alternating straw & black weave as Wenonah’s Kevlar? If not, Bell’s Kevlight and the older Kev Crystal might share also have Kevlar on the outside of the hull. Actually, looking at my Bell Kevlight hull with a bright light shining through, it really looks like there is only one layer of fabric at many (but not all) locations above the waterline. If that’s true, the outer layer over the whole hull would have to be Kevlar unless the fabric itself is a blend. Any ideas or direct knowlege about that?
my Bell Kevlite boat
– Last Updated: Mar-10-09 10:13 PM EST –
has one layer and one only on most of the sidewall, stems excepted.
I know because Dr.Wilson is going to apply some patches on the folds where all the Kevlar fibers are stressed due to my . Plus of course your light findings.
Not even a belly band.
The bottom is another issue..there would have to be a layer of Kevlar below the foam panel and it looks like Kevlar atop the foam.
I too would be interested to learn if there is a fabric that is a mix of materials in one piece.
Its a nice boat to take for a walk.
GBG are you talking about Souris River El Tigre layup? I dont think (but do not know for sure) that the black is Kevlar rather than carbon.
Lay-ups again
Kevlar is tough. No doubt about it. Just like spider webs are tough, though, one needs to use enough of it.
Wenonah uses enough kevlar in a Minnesota II ultralight to survive careful use in the boundary waters. They don’t use enough to be comfortable on a river trip further north (though, of course, they have canoes for that purpose too).
Aluminum gets all the respect it needs. It is pretty tough, but not nearly the toughest material out there. The reason I don’t like aluminum has nothing to do with its toughness and everything to do with its design limitations. Show me an aluminum canoe that is anything like a prospector (some rocker, good arch in the hull). I’ve seen many shredded aluminum canoes, and have done enough damage to Royalex to know it is far tougher.
Properly wetted out and laminated fiberglass looks like glass - that is to say transparent. It is difficult to tell if a boat has a glass outer layer. My Souris River does - it is a light e-glass.
Tough enough is all we need, after that, it is important to find boats that handle well. Having a canoe that is only tough is like having a car with big bumpers and airbags but bald tires and fading brakes.
Lay-ups again
– Last Updated: Mar-11-09 10:20 AM EST –
Oh - and I am pretty sure that the Souris River lay-ups have no carbon fiber. Just black kevlar and gold kevlar. These are the same - just cosmetic.
Don’t know about the details of the
Souris Tigre layup.
johnrsweet.com sells a cloth where Kevlar and carbon strands alternate in both warp and woof. I have a sample to try. CE Wilson has pointed out on p-net that it might not make sense to mix Kevlar and carbon, because under high stress, the Kevlar fibers may split neighboring carbon strands due to big descrepancies in how the fibers respond to load. (At least that’s what I think he said.)
sweet also sells a cloth where S-glass and carbon are interwoven. This combo might make more sense. The S-glass is heavier, but a little tougher, and if used at the outside of the boat, the S-glass strands will tend to partially shield the carbon strands from abrasion. But why not use just S-glass outside, and carbon for the next layer?
By the way, S-glass often does not wet out “clear” but may remain milky or a bit creamy.
My Dagger Zealot slalom c-1, a one-off experimental layup, has 2 layers of S-glass outside, and two layers of carbon inside. While there is Kevlar on the foam core deck, as far as I know there is no Kevlar in the hull. The boat is 22# and extremely stiff. It has never cracked under routine pounding, but if it ever takes a really big shot, it will be brittle. I wish it had Kevlar inside as insurance against catastrophic crack propagation.
Kevlar/carbon colored cloth source
Here is a link to one source of a mixed cloth with dyed Kevlar and black carbon. Just so anyone can see what is offered.
http://www.fibreglast.com/showproducts-category-Hybrids,+Carbon+&+Kevlar±+Fabrics+&+Tapes-16.html
Layup
– Last Updated: Mar-12-09 10:11 PM EST –
No, I know nothing about Souris River boats. I was only talking about the boats I actually mentioned when describing that kind of fabric.
I'm pretty sure you answered the main part of my question though, which is good since nobody else tried. I THOUGHT my Merlin II looked like a single layer at most locations above the waterline (though there ARE a few spots where it is clearly made of two layers), and since you have found out that that is indeed the case, then it must be true that Bell's Kevlar hull is "Kevlar on the outside" (it couldn't be anything else if the single layer of Kevlar cloth on the sides seamlessly rounds the corner to the bottom of the boat). That of course means Wenonah isn't the only boat maker to do that. For what it's worth, I'm pretty sure the Wenonah Kevlar hulls are only one layer thick at most locations above the waterline too.
Regarding the two-color fabric, somebody posted here once that it's a cosmetic thing and that the two colors are not two different materials (and now canoe_head has just said the same thing), but I don't pretend to know for sure. I only mentioned that characteristic as a way of making it clear which hull material I was actually talking about, since everybody knows what that stuff looks like.
hit the link
and add the words Carbon+Kevlar in the search function
The whole link did not copy.
Sorry about that. Hadn’t run into that
problem before. On further searching, there are sources for all-Kevlar where the fibers running one way are dyed black. And it appears that is what Souris is using in their Tigre layup.
Generally, though, there has been more interest in mixed carbon/Kevlar cloths like the sample I have. I’ve grown sceptical, however, that a Kevlar/carbon weave makes sense. They are two fibers so different in behavior under stress that they may not work well together.
Still great boats!!!
Holy cow, I thought I’d never hear Mad River Kevlar Explorer as a “beater”. That hurts, it use to be the cats ass back in the 80’s! Anyhow, I have one, bought it new in '83, you can carry a ton of stuff, and do class 2 whitewater all day and not worry. You want to be respectful and not just run into rocks like a plastic boat, but it was, and still is, a great wilderness boat!!!
related topic…
This is an interesting discussion and I think enough enough discussed to shift gears a bit. I’ve paddled the Buffalo 6 or 7 times and put-in at Ponca twice, and have yet to see what I consider a class II rapid. I’ve only seen a couple of Class I rapids. Have I just not seen it at higher levels? My experience with judging rapids is from the Occoee, Nanty, and Chattogga type watersheds.
What I remember compared to …
– Last Updated: Mar-26-09 6:45 PM EST –
... the typical rating scale:
First off, here's the scale I've seen most often.
"Class I.- Easy. Smooth water; light riffles; clear passages, occasional sand banks and gentle curves. The most difficult problems might arise when paddling around bridges and other obvious obstructions.
Class II.- Moderate. Medium-quick water; rapids with regular waves; clear and open passages between rocks and ledges. Maneuvering required. Best handled by intermediates who can maneuver canoes and read water."
The fact that you've only seen "a couple of Class Is" when putting in at Ponca tells me you are not using anything like this scale, but this is the one I know so this is the one I'll refer to.
The one time I was there, the water was dropping so that it was no longer possible to put-in at Ponca. People who had been there the previous two days said that below Ponca the swift water was so nearly continuous that they had to constantly watch the rocks rather than enjoy the scenery. Several reasonably experienced boaters flipped. These are people I know, so based on the scale provided, there was certainly a lot more than "a couple Class Is" on that stretch.
On the next stretch below, which is what I ran three days in a row, starting at Kyles landing, I don't think I could count the number of Class Is using the scale provided above, and using the Class-II definition of having regular waves and it being necessary to maneuver to avoid obstacles, I'd say there were quite a few Class IIs as well, though they were easy enough for anyone who knows what they are doing. I had a Wenonah Vagabond, and there were several rapids where the waves came over the bow with plenty of room to spare, so there was water to bail afterward, so if only using the size of the standing waves, there were more than a couple of Class-I drops on that stretch.
It's clear to me from reading posts by some of the regulars on this board that a lot of people apply a much higher standard to Class-II rapids than that used with the scale I quoted, and apparantly you are in that camp. Why so many of the rapids with swift water with strong turbulence and numerous one-foot waves (or bigger) doesn't even rate being called a Class I in your book surprises me though. As I said, I know the water was not high when I was there because the stretch below Ponca was too shallow to paddle.
Anyway, that's my two cents regarding your topic.
Y’all might want to move rapid rating
discussion into a separate thread, on the Paddlers Discussion Board. It’s an important topic, and will not be noticed at the end of a Kevlar boat thread.