Going with your kayak over oyster beds, shells, sharp rocks, broken glass, metal debris and even concrete ramps can get its hull scratched. In most cases such scratches are negligible, and you need not pay attention to them. However, if you want to avoid getting your kayak scratched you’d better watch out for signs of such potential hazards in the water – especially if you’re fishing or paddling in shallow water. Needless to mention is the fact that fishing and paddling from a higher position than ordinary kayaks offer you can help a lot in detecting potential problems in the water ahead of time, that is before hitting them. This is yet another advantage the W Kayak offers you, and W Kayak paddlers and fishermen indeed stand up in their boats from time to time to look at the water around them.
When it comes to repairing scratches in polyethylene kayaks the methods are similar and depend on how deep the scratch is.
For superficial scratches we don’t recommend any treatment, but if you insist on doing something you can just flame the scratch using a hand-held, propane blow torch. You should apply the flame over the scratch slowly and cautiously until it disappears or diminishes considerably, while being careful not to overheat the area so as not to cause a local deformation. In any case, flaming alters the color of the polyethylene to a darker hue.
For deep scratches or ‘grooves’ it’s better to heat the end of a metal spoon and apply the hot tip gently and cautiously along the scratch, thus ‘welding’ the surface. Here too, you need to be careful not to overheat the area you’re working on since this would cause the polyethylene to deform. You’d need to protect your hand that’s holding the spoon with a thick glove since metal conducts heat and you might get your fingers burnt.
Keep the work area free of any flammable materials and make sure you’re not accidentally directing the flame at yourself or at other people. Don’t allow children or pets nearby.
If you’re not experienced in working with a propane blow torch you may want to reconsider such a project because it can be dangerous.
As for cracks in a polyethylene kayak, those are rare, and they must be properly fixed. Just flaming or welding won’t be enough to fix a crack, and you’d need to patch it – preferably with an internal patch that you’ll weld over the entire area. This is necessary since even if welded the hull in the cracked area will be weaker than in other places, and it could reopen while you’re paddling your kayak or fishing from it – with dire consequences. If the crack appears above waterline you can reinforce the patch with rivets, but we recommend not to use rivets when making repairs below waterline because we think that drilling holes in the hull below waterline is simple too risky in the long run.
Do you have any questions for us?
How about fixing a crack in my sot kayak? There’s no way I could patch it from within the hull…
Fish Wiz… looks like you’ll have to give up this project.
BTW, how about using glue to fill scratches, glue patches and so on?
Bill
Polyethylene doesn’t bond well to any adhesive because it has a low surface tension. You can use strong adhesives to fill very small holes and very narrow scratches but I would certainly not recommend it for use anywhere in your kayak that’s under water.
Good point on the higher level of seating in the W. I can attest to the fact that you can see much better than any sit inside or SOT boat out there. I just take it as second nature I can see problems and avoid some of them because I’m so much higher.
Jeff
You can definitely weld Polyethylene as long as its not cross-linked, and it will be strong, you just need to do it right.
Drill the ends of the crack so it doesn’t spread, gouge the crack out so you get good penetration of the weld, and then use the same type of plastic.
Good luck it’s not hard to do. Just take your time and don’t over heat your boat.
Chris,
You refer to gouging the crack out and good penetration of the weld, so it sounds like you’re talking about a very thick wall, such as you’d typically find in the lower side of whitewater kayaks 😉
Welding such a crack without reinforcement could work to some extent (its not fool proof) but only if it’s undeveloped, straight, and relatively short. But welded areas are weaker than the wall around them, so for longer cracks and thinner walls the method you’re talking about doesn’t necessarily work, and such cracks require additional reinforcement, such as this article describes.
BTW, instead of drilling the ends which creates a full perforation, try ‘scrambling’ them with the tip of a soldering iron – You’d get the desired effect of limiting the crack’s expansion without the unwanted consequence of needing to fill holes.
And last but not least – People don’t have electric hot air guns at home. They have simple blow torches that produce a flame that’s not easy to control as the flow or hot air coming from a heat gun. This makes welding much harder for them, and it can lead to accidents.
I checked with the guys I bought my kayak from and they recommended using a hairdryer and your finger, lol. Guess I will give it a shot.
Andy,
While a hairdrier doesn’t generate enough heat to melt the surface of the kayak wall, it can generate enough heat to soften and warp it, and while fixing scratches in your kayak is relatively easy, and fixing cracks harder, fixing warped walls is quasi impossible.
Why not try something like gorilla glue. It is waterproof.
I’ve never used this brand, but if it adheres well and it’s waterproof, it should work too.