I'm looking for a kevlar canoe that can stand up to a little bottom dragging on shallow rivers. From what I have read it appears that some kind of kevlar/spectra blend may be best with epoxy resin. Who besides Souris River makes such a craft in a 15'to 16'length? Also does anyone know how Nova Craft's "blue steel" would hold up to the above conditions. I have no problem performing a refinishing job every few years to repair scratches, I just don't want to have to repair holes.:)
I would also like to say "Thank you" to everyone on this board for the advice that you have given me over the past few weeks. What a great resource!
Hellman? Clipper?
– Last Updated: Sep-16-07 6:30 PM EST –
Toughest is debatable (and likely will be debated).
I suspect that the toughest canoes will have more material. Besides souris river (who actually just came out with a new laminate for whitewater . . . maybe they could use it in another design for you?), look at Hellman Canoe's duratuff and Western Canoeing/Clipper's Duraflex.
If you have the cash, Kruger Canoes are made with many layers, and are reputed to be very very tough. If you have that kind of money, though, please send some my way as well!
Avoid ultralight foam cores which give good stiffness for performance at the expense of resiliency.
Let us know how you make out.
Which is important to you? Resistance
to bottom dragging, or resistance to “holes”?
Kevlar is a lousy outside material because it has low compression strength and fuzzes when worn.
Even Kruger put a glass layer on the outside for wear. If you want wear resistance, you want S-glass on the outside. If you want resistance to “holes” produced by impact, you want S-glass outside and Kevlar inside.
The composite fabrics are great for builders, but the carbon fibers will wear through when dragged, and the Kevlar with then fuzz.
Hemlock Eagle
As previously stated, you do not want a Kevlar outer: either carbon or S glass, preferably the latter.
Also as previously stated, you will be unhappy with a cored boat. They damage fairly easily and repairs require opening up the foam cover, scraping the foam out, then repairing the outer, replacing the foam and then repairing the cover. Ugh!
Spectra is fine stuff to eliminate weight and give high tensile strength to carbon, but it delaminates pretty easily and is often not repairable. Fine combination for a race boat, poor choice for a recreational boat.
A wonderful solid fabric tandem with S glass outer and Kev interior is Hemlocks Eagle. The premium hull has the S outer layer. It’s a fine hull, tumblehomed so smaller paddler can paddle bow, and it solo’s pretty well when the third thwart is replaced with a kneeling thwart.
Thank’s for the quick replies!
Since the Ohio Valley is not know for it’s treacherous white water, I think I would be in greater need of resistance. So based on that it seems that I should be looking at boats that incorporate s-glass. I took a look at both Hellman and Clipper and it appears that Clipper uses this process. Now if I can figure out to find a dealer near Ohio. I may be out of luck.
Thanks again.
Hemlock Canoes
What a great website. The Eaglet looked interesting. My only concern is that I wonder how stable it would be at 321/2" wide? Thanks for the recommendation.
Call them
A few local paddlers have visited them and said that Dave Curtis is very helpful!
Souris River Duralite
Have worked very well for four years of three month a year tripping in northern Ontario where there is a LOT of lining and tracking due to whitewater…or plain running the stuff if conditions are right.
The rib system (without a flat bottom panel) allows the canoe to oil can over rocks yet on the flats the craft does NOT oil can.
Duralite looks like Kevlar but is not, its more abrasion resistant.
s-glass vs. e-glass
S glass is a bit stronger, but I am not sure it is necessary. Likewise, I understand epoxy has a bit more strength, but shouldn’t be the determining factor.
For example, I don’t know if in actual use you would have any difficulty with either the Clipper (which uses a high-tech vinylester), or Souris (which uses e-glass. All these quality builders know much more than we do, and combine materials for the best results. Point being, I wouldn’t get hung up on little technicalities like this, especially if you find the hull shape/design you want.
Agree about vinylester, but S-glass
– Last Updated: Sep-16-07 9:50 PM EST –
is enough better than E-glass to justify its use. And I do not accept that "all these builders" know more than we do. I know why I prefer Hondas to Chevys, because I know what is in them and I know what works best.
Stewey, check out the millbrookboats.com site. Kaz makes some very light, very tough boats, S-glass outside and Kevlar inside. While his designs such as one might use in Ohio (AC/DC. Patriot, Rival, possibly Swamp Hen) are not as sophisticated as those of Hemlock etc, they are all very good performers, and his prices are very reasonable.
toughest
If you define toughest by the #number of layers of Kevlar its obviously the Kruger Canoes with a total of 12 layers in the hull.
ALL other production canoes in North America with kevlar have between 2-4 layers but mainly 3 being the majority…so the Kruger is 9 layers thicker.
I own one…had to come off my truck at 50mph because i spaced tieing it down…watched it summersault end over end about 8 times…nothing is wrong with it…a couple scuff marks. One of Verlens demonstrations (when he was alive) was to take a sledge hammer to the hull and show you how it would bounce off. Its a good sales pitch
glass outside kevlar inside
Swift has several kevlar layups including a rather bombproof kevlar/glass combo. Very rugged but not so light.
Correction . . .
I suppose I should have said that the builders know more than “I” do, not more than “we” do (We might include the builders for all I know).
I can’t recall why Souris River said they used e-glass, but when I toured the factory, they did give me a reason.
I prefer Honda’s too, though I don’t know why.
Ultimately, though, my point is that within reason, the right shape will be more important than the right material.
lamination engineering
– Last Updated: Sep-17-07 9:24 AM EST –
If Kruger used 12 full blankets that explains why the boat is so bombproof and so damn heavy. Many boat builders use lamination schedules with partials to place more layers where needed and fewer where not.
For example, Placid Boatworks 12 ft SpitFire, 19 lbs with pack trim, has 11 layers in the stems, 5 layers in the bottom and seven in the cockpit area. Partials are often placed on the bias to improve performance. I know for a fact that Bell, Hemlock, Mad River and Swift use similar partial schedules.
Swift, WeNoNah, Mad River and Bell also use Foam in place of partials; lighter, more difficult to repair.
We iuse an epoxy-vinyl ester resin - almost as light and strong as a full fledged epoxy but better for our health and UV degradation, which our customers appreciate, because they expect the hull to last decades.
Then we need to consider lamination methods. Good hand laminators achieve a 45% fiber content. Vacuum Infusion, dry bagging, brings fiber content up to 56% plus eliminates voids, which weaken laminae. Wet bagging eliminates the voids, but doesn't remove much excess resin. Autoclave vacuum procedures using prepreg fabric brings fiber content to 58%, but the prepreg costs 2.5X for the cloth, requires a cold storage room and the use of a million dollar autoclave.
I know that NovaCraft, Swift and PB infuse. I Do not know what procedure Bluewater, Bell and Wenonah use. Hemlock used contact lamination.
Tough hulls
As you continue to look at all these very good (and well explained) suggestions , I encourage you to continue your interest in Nova Craft’s Blue Steel layup. Yep, it’ll scratch right up and the scratches are particularly visible w/the standard clear gelcoat against the fabric’s dark blue background. However, to actually put a hole in it is a different story; this is tough stuff. Mine has 4-5 years of real abuse and shows it; but nothing approaching a hole has ever occured. And, it is pretty light for that kind of strength (though certainly not cheap). I’ve also had good luck w/Wenonah’s Flexcore, a wholly different approach from the Blue Steel. It really does “flex” when their Ultra Light won’t.
It’s good to read
about the Kruger boats in a Tough Boat thread. No doubt if Kruger Canoes used all full blankets of Kevlar it would be quite heavy indeed. However that’s not the case. Having helped lay up a good number of Kruger hulls and decks, I can tell you that all the Kevlar layers are not full coverage layers. The pattern, placement and cloth type used are engineered to provide a very durable boat. Perhaps the most durable canoe on the market, yet still within an acceptable weight for an expedition canoe of 62 lbs. Add to that a very comfortable, padded built in balanced portage yoke and it caries nicely.
You’re right, builders have their pet
beliefs too. And Souris River canoes are well-made and tough. But the number of irrational statements they make on their website about the construction approaches of others should make one take anything they say about S-glass versus E-glass with a grain of salt.
Something many builders don’t own up to is that they may make compromises to save the buyer a little money. There is nothing wrong with this, as long as you 'fess up to it when asked directly. Souris River does not make any hull designs likely to be used (and hammered) in whitewater, so using E-glass rather than S-glass may be quite acceptable, saving the buyer a little money. But they could go farther, replacing a layer or so of Kevlar with CAP, and using quality vinylester rather than epoxy, and they might save more money without losing any toughness.
But that would catch them right in their ideology, because they’re wedded to epoxy and Kevlar, just like they’re wedded to flat bottomed stability.
could be marketing
s-glass costs a lot more than e-glass, almost as much as kevlar, with no visual difference. Kevlar looks different. From a marketing and customers standpoint why buy something that costs more but looks the same?
I made test panels with e-glass and s-glass on plywood panels. Using the edge of a knife or screwdriver it was obvious that you could wear through e-glass more easily than s-glass of the same weight.
an old Mad river canoe?
That’s a conventional gel coated not so light kevlar hull
Agreed on the Eagle, one tough nut
to crack. At about 55 lb. for the Kevlar lay-up the only thing that comes close is an old Jim Henry Vermont built Mad River Malachite or Explorer in expedition lay-up. Both of those were stable boats and pretty bomb proof and are getting harder and harder to find. The Eagle on the other hand is actually 35.25 wide , 32.25 at the 4 inch water line. It is fairly responsive for a big tandem tripper and has good speed. Two good paddlers can make this boat dance. Secondary stability is excellent while initial stability will feel a little tippy to a novice but that goes away with learning the boat and what it’s capable of. The more you put in it for the trip the more stable it will become. Excellent tandem if want to get lost in the Norther wilderness and forgot your duct tape.