Need help repairing Royalex canoe

Just bought a used Mohawk Royalex canoe. The guy owned it for 10 years and used it quite a bit. There are small scrapes all up and down the bottom of the canoe (not a big deal I know). However there are 2 good gouges that go down to white (the core I understand). These should be repaired I presume. How do I go about doing such a thing?

The first you could shove a quarter through. The 2nd you could maybe shove a nickel through. They both expose white. I read that it’s a vinyl/ABS/core sandwich. Doesn’t seem like I have the outer vinyl, All I noticed on these deeper scratches was the thick plastic outside and than it hit the white inner. Didn’t notice another layer.

I think I read I could use 3M structural adhesive? What do you guys think? Can get some pictures if that helps. Gotta trip on MOnday, gotta get this thing ready to go.


The core is foam.
If it were exposed, you’d know it. The outer vinyl skin is there to protect the ABS from UV. Browsing the archive should tell you everything, and more, about what folks recommend. Otherwise, you’ll hear from the experts soon.

Not urgent
None of those repairs sound at all urgent, so your trip should be a go regardless. If you can see foam, cover it with duct tape.

I like to use epoxy for deep gouges or structural repairs. Spraypaint for anything shallower. For a couple small gouges, something like JB weld is cost effective, and is basically an epoxy anyway.

The only purpose of the vinyl is to protect the ABS from UV damage. As such, any sort of paint will work fine. I’ve used Krylon fusion with good results, though it takes a lot to get good coverage. 303 or armour or wax would work too, but you can’t be as certain because you can’t see them working.

maybe just paint
If the foam core isn’t exposed, you might just need to cover the exposed ABS (the white areas) with paint like Krylon fusion, for UV protection.

The 3M structural adhesive will work for small punctures and gouges. It is relatively stiff when cured but adheres very well to ABS. It is a bit more difficult to smoothly apply than epoxy, however. If you already have it you could use it.

Nowadays I would use WEST Systems G-flex epoxy for this type of repair, although Plexus will also work. Either can be purchased in relatively small quantities for simple repairs.

I’d fill them with whatever epoxy I happened to have on hand.

this may take awhile

– Last Updated: May-05-11 9:48 PM EST –

but if you read the thread, click the link in that thread, read the thread the link linked ya to, click the link in that link....

did this one with the g-flex

I’m a little confused now after some of these posts.

My understanding was that there is a very thin vinyl outter layer followed by a green (usually) ABS plastic followed by a white foam core. I was initially confused b/c I have a green canoe and I found it hard to tell what was vinyl and what was ABS. I think I have that cleared up now. The two gouges show white which I understand to be the core right?

I did a lot of searching before posting this so please don’t think I didn’t take the initiative here. I went looking for the 3M 3532 urethane adhesive people reccomended and didn’t find anything locally. It’s like $22 online though. Didn’t find a comparable alternative locally for about the same price. I also have some JB WELD on hand I could use too. I like the ABS pipe/acetone slurry idea. Sounds like the most professional repair. I might duct tape it or JB WELD for the trip and than look into the slurry route when I get home. Good?

There’s more than one way to skin a cat
Everyone seems to have their favorite method of repair and a number of different methods will work.

On older Royalex the ABS substrate was most commonly green, but on some of the newer stuff made by Spartech corporation it is white. If you see something that is white and looks solid, it is almost certainly the ABS solid substrate layer. If it is white, off-white, or tan and looks like Swiss cheese, it is the foam core.

I can’t comment on JB weld because I have never used it. A number of folks here seem to like it, so I assume it works. I have tried the molten ABS method and, at least in my hands, found it wasn’t as durable as I would have liked.

As I said before, the 3M structural adhesive will work if you have it, but IMO it has not advantages whatsoever over epoxy or Plexus. It seems to be much stiffer when cured than Royalex, which may be a disadvantage, creating a stress riser at the edge of the repair.

If you use ABS dissolved in acetone or MEK, you must protect the foam core from the solvent, because either will dissolve it, ergo the Gorilla Glue. If you use G-flex or another epoxy, you do not need to apply Gorilla Glue first to seal the foam core.

By the time you spend the money for either 3M structural adhesive, or acetone, ABS, and Gorilla Glue (unless you have those things lying about at hand) you could have purchased this:

This will give you plenty of G-flex to repair the damage as well as some spatulas, mixing cups, gloves, syringes, and some silica powder to thicken the epoxy if desired. G-flex mixes one-to-one (resin to hardener) by volume so small batches can be mixed by eye without need for metering pumps or other measuring devices. It has a longer “pot life” than 3M structural adhesive, and is easily worked and sanded.

I gotta’ say I’m happy with the bow repair I did using g-flex (link above). I’m not babying that boat at all, smacking the bow when getting sucked into rocks eddying out, and it’s not showing any wear.

You’ll know it…
if you’re into the foam, because it will look like FOAM, not solid. On plenty of Royalex canoes the first layer beneath the vinyl, the solid ABS, is white or off-white.

I have used a lot of JB Weld, and it works fine on small gouges, but don’t use it to cover larger areas, say more than an inch across, because it dries very hard and somewhat brittle, and will crack. I found some epoxy made for repairing plastic in the local big box store. It’s clear, which doesn’t do much to protect the ABS from UV rays, but it’s about the same grade of flexibility as the canoe materials, so it doesn’t crack. I’ve been thinking about experimenting with mixing some paint in it as I stir it up to add more UV protection, but don’t know how that will affect the cure.

just bought 12’canoe with gouge in it
The store gave me a discount on the boat and said to go to Home Depot and get either outdoor silicone sealant or outdoor epoxy. The RoyalX has one bad gouge going past the colorful green outer layer to the white inner more side. From reading the posts in this chain, I don’t believe it to be all the way through to the actual core but more to the solid white part before that layer. I’m a single female and this boat is basically for me to take my dogs out on. I hope it is a project I can do alone as the boat was $500 Old Town Pack they assured me should be selling for $780 sans gouge.

The staff assures me some supplies as listed above should be all I need, however reading your post with the Gflex kit link seems like I should choose that route.

I also found this useful link to a pdf titled “Repairing Royalex Canoe Hulls by Nelson Highley”

The latter seems so useful but limited craftsmanship may lead me to the former repair kit option.

Any advise is well appreciated!