How to Smooth Out Scratches on a Polyethylene Kayak

how to repair a kayak

One of the unfortunate inevitabilities of owning a kayak is getting scratches on the bottom of its hull. Whether you’re navigating down shallow rivers, or paddling along pebble shores, your kayak will likely pick up a lot of scratches on its hull just from normal routine use.

While most of the time these scratches are just cosmetic and won’t impact the utility of your kayak, if there’s enough of them they can eventually cause friction with the water which will reduce the efficiency of each of your paddle strokes. This is because the kayak will not glide through the water as sleekly as it should.

In this article we will teach you the best techniques for getting rid of these scratches and restoring your kayak to its former glory.

Removing the curly whirlies

When your hull scrapes against something, it displaces some of the polyethylene. Often this won’t come fully off, and there’ll just be lots of stringy bits of plastic left on the bottom of your kayak. The first step is to remove them.

To do that you can use a ‘razor scraper’, which you can pick up on amazon or ebay for a few quid.

You’ll just gently slide it across your hull until all the curly whirlies have been removed.

Sanding out the shallow scratches

The next stage is to get rid of the shallower scratches in the plastic. To do this you’ll want some medium grit sandpaper. Sand down the bottom of your hull using a circular motion until only the deepest of the scratches are still visible. This is a bit of a long process, but the results will be worth it.

Filling the bigger scratches

Some of the scratches will be too big to sand down without compromising the integrity of you hull. For these scratches we’ll need to fill them in with some spare polyethylene. You will need to go on amazon or ebay and buy some scrap polyethylene that’s the same colour as your kayak.

Next you’ll need to get an old pan you don’t mind ruining, put it on the hob on a very low heat, and put the polyethylene in.

Once it has melted use a knife to apply the plastic to the scratch making sure to smooth it out as much as possible. Once that’s done for all the scratches, leave it a few hours to dry and harden.

Sanding down the filler

Unless you’re very good as spreading with the knife, you’ll have uneven bumps where you added filler. Sand these down with the medium grit sand paper.

Final sanding

Now take a finer grit sand paper and do one more sanding of the hull. Again, you’ll want to use a circular motion until the hull is smooth to the touch.

Adding the wax

Finally, you’ll want to wax the bottom of your hull. You can buy special made kayak wax from amazon for not much money. It’s generally meant for fibreglass hulls, but it’ll work fine on plastic too.

Put some on a rag, and work it into the hull using a circular motion.

And you’re done! Much cheaper than buying a new kayak.