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Boundary Waters Quetico Forum :: Group Forum: Boat Builders and Repair :: Epoxy in screw holes?
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03/12/2022 07:12AM

I too should have been more thorough with my reply.

I’ve built well over a hundred wood canoes and screwed the gunwales on every one. I use epoxy on the surface that meets the boat and countersink screws through the gunwales into the hull. Outwales go on first by driving a screw through the hull to the gunwale and inwales go on last. The inwale screw goes through the hull and into the outwale.

I do fill the countersink holes with a wood plug of either the same species of wood as the gunwale or sometimes an alternating color of wood for a striking appearance.

With that, I have never had an issue with rot. For me, I take good care of my canoes but I know a lot of people do not either because they are poor stewards of their canoes, ignorant to storage practices, or don’t have a place to store them out of the elements.

Of all the gunwale issues I’ve seen out there, it’s the gunwales at the ends of the canoe where a canoe is flipped upside down on the earth for some time and the entire end of the canoe starts to rot where it rests in the dirt.

I have also seen gunwales start to rot away when stored the same way outside above ground where the wood is not protected. However, the screw holes don’t seem to favor rot any more than the rest of the gunwale. Wood gunwales left wet for long periods will start to decay. Keep wood canoes dry and they last generations.

As far as strength goes at a screw hole. All I can say is I have canoes with thousands of miles on them and the gunwales have never been a strength issue. Even when on the car zipping down the freeway at 75 mph. That canoes is flexing, twisting, rubbing, and trying to get way but never lets loose.

03/12/2022 08:06AM
I totally agree with screws on Wood Canvas ! Screws rule !
The way a canoe is stored, or left on the ground with gunnels making ground contact, is highly detrimental. A Sin in my book. In those cases ? It doesn't matter how you mount your gunnels ! AMEN !

CabSauv is building a cedar stripper, and I would highly recommend, gluing, for the reasons I previously stated.

That is his choice. I'm glad we were able to provide different options ! That's what makes this world go around.

03/09/2022 08:44PM
My build is moving very slowly but it is moving. During some downtime today I was reading about attaching gunnels. My inner gunnels are done and I’m about to do the outer. One builder adds epoxy to screw holes with a pipe cleaner to prevent water from getting access through the screws. Is this an issue? Does anybody do this?
03/10/2022 12:48PM
I don't agree that screw holes weaken gunwales

Dip the threads of your screws in the epoxy before you drive them in.
Your gunwales will rot if you leave your canoe outside in the elements and don't treat them with oil or varnish.

03/10/2022 01:20PM
Dipping screws in epoxy or varnish is a good idea. If you are not gluing your gunwales then you also need to seal the surface that goes against the hull before you put them on. If you don't they will rot from the inside out. I used to seal mine with watco oil(teak version) as that was what I used to treat the outside surfaces. Later I coated the inner surface with epoxy, still treating the outside with Watco. These days I glue the gunnels on and coat the outside with epoxy and varnish.

Screwing gunnel on allows for easier replacement for sure, But I don't think I will ever have to replace the glued ones if maintained properly.
03/09/2022 09:52PM
Never tried it. I glue my outwhales on. They are stronger, and seal out moisture, that rots the gunnels.
Screw holes weaken a gunnel.
rotten gunnel
03/13/2022 05:54PM
Thanks you guys! I’m on my way with the next phase. We’ll consider this thread done.
03/10/2022 08:51PM
Thanks for a great discussion! To be a little more complete, I’m attaching the ash gunnels and cherry decking to my cedar strip with epoxy and was going to add brass screws partly for the look and partly for reinforcement (yes they will add a little weight). Dipping the screws sounds solid to me, but will the screws be counterproductive? I’ll varnish everything when I’m done, and as long as I can lift a paddle this canoe will be stored inside.
03/10/2022 07:32PM
tumblehome: "I don't agree that screw holes weaken gunwales

Dip the threads of your screws in the epoxy before you drive them in.
Your gunwales will rot if you leave your canoe outside in the elements and don't treat them with oil or varnish.


I've replace several sets of gunnels. Some of them fell apart as I removed the screws. Where did they fall apart ? At the screw holes. Want more pics ?
When you think of it, The only place a screw holds the gunnel tight to the hull ? Is at the threads of the screw. This gives water a lot of chance for rot.
Gluing, holds the gunnel tight to the hull the full length of the gunnel, and seals out moisture .
Keeping the gunnels dry is by any means the best way to preserve them.
03/10/2022 07:48PM
Sorry Tom ! I didn't mean to sound argumentative !
The original poster didn't state what kind of hull he had. I should have asked that first !

There are instances, where it isn't practical glue gunnels. Royalex, and Wood Canvas, are two !

The last two sets of gunnels I replaced ? Where on Royalex hulls. In both cases, the hulls had been abused. Had the manufacturer used your method of coating screws, maybe they would have lasted longer ?