Kevlar stress crack help

Hi all, brand new user online here.

We purchased a souris river quetico canoe this spring. Have spent many wonderful days tripping with it this summer. Unfortunately on our latest trip we were running some river rapids and had a bad run in with a rock and damaged our beautiful new canoe.

I’m a complete novice when it comes to canoe repair. I’ve read some of the repair advice that souris river has on their site, but I’m just not sure what kind of repair is needed here.

It may be too difficult to tell just from pictures, but I’m hoping for some advice on what needs doing.

Option 1 - sand down and reapply new epoxy resin over the damaged area. Revarnish and polish to make it look pretty.

Option 2 - sand down and apply fibreglass patch to outside with epoxy and then varnish.

Option 3 - apply Kevlar patch to inside, fibreglass patch to outside and varnish.

Option 4 - bring it to someone who knows what they’re doing a pay them to fix it.

The canoe holds water and still feels pretty sturdy in that area. I don’t know how intense a repair it needs.

Any advice would be appreciated.

I’m not seeing any torn or cut kevlar. It really seems to be mostly cosmetic looking at the photos. I think the epoxy is scratched and stressed a bit. It’s my understanding that Souris River uses a thermo cure epoxy. There is no varnish. Therefore a repair would be some light sanding and followed by a light coat of epoxy. It’s never going to look new but it can be made to look less obvious. I see no need for a patch since the kevlar is intact.

Thanks for the response. I think I will have a go at sanding and epoxy.

Just make sure not to use coarse abrasives. Lean toward fine and wet sand.

Aramid fiber (of which Kevlar is a variety) has extremely high tensile strength. One of its weak points is that it does not take up resin and bind into the resin matrix nearly as well as most other fibers such as fiberglass. So a strong impact will often result in the fibers not tearing, but disassociating from the resin matrix. That is what causes the little white lines.

The fibers are still intact but strength has been compromised to at least some extent because of this disassociation. How much is hard to say. You can try applying some epoxy but I don’t think it will completely eliminate the visible damage. I would push in firmly on this area and determine whether it has any more “give” than other areas on the hull. If it does or if it feels at all soft I would patch the interior, which won’t show. You could use either fiberglass (more cosmetic) or aramid cloth for that purpose. Aramid would have a bit better tensile strength than fiberglass and would be a little lighter, but for an interior patch the difference would not amount to much.

If that portion of the canoe feels as solid as the remainder and there is little or no visible evidence of damage on the interior, I would not patch it.


If there is any real damage it is most likely a crack in the epoxy and not the cloth.

To judge that would from a look inside. Epoxy is more likely to explode and not implode.

Be sure to check it and not make just surficial repairs. Just repairing the outside will make a weak spot that is more prone to flex. That flex will cause it to keep cracking the epoxy.

The inside would be best filled with several thin coats of epoxy (outside too) rather than one thick coat. After it is filled make sure it cures through and check to see if it flexes more than elsewhere.

If it does add a piece of something like Nida-core on the inside. That is the foam used on the floor of most Kevlar canoes.

I had similar looking damage on a composite canoe that had a branch fall on it; felt solid enough but had obviously been compromised. It likely didn’t even need repair but I was lucky to find a local amateur canoe builder who gifted me some of his epoxy and hardener and a piece of aramid cloth. So I patched it on the inside and brushed on a little epoxy on the outside. Not perfect but fine by me. If you don’t have someone close by to give you an opinion, there is a very helpful Canoe Outfitting & Repair group on FB.


I picked up some epoxy and hardener earlier today. Did some light wet-sanding and a couple thin coats of epoxy on the outside over the course of the day. I’m pretty happy with the way it looks (not perfect, but much improved). I’ve attached an updated picture for comparison.

It feels very good the way it is, but just as an insurance policy I think I’ll throw a patch of fibreglass on the inside, since I’ve got the epoxy already. Maybe it’s not necessary, but can’t hurt either.

Thanks for the advice and help everyone. Much appreciated!


I’d more than likely stiffen the inside if it feels any softer than opposite side of the hull in same spot.

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