Kayak taking on water(help)

anyone ever fixed a kayak by plastic welding?

My wifes hobie sport is taking on water with a hairline crack. I have identified the problem area and i am trying to find the best solution for a permanent fix

I am a little wary of glues and bonds- i am afraid it will penetrate the crack and then expand it into a bigger problem.

I ordered a kayak fix welding kit but I have no experience in this. The KC welder pro which comes with some Hobie color rods to use

all suggestions helpful



Some folks have reported good luck with the west Systems G/flex epoxy. It’s designed for hard-to-bond surfaces.


In theory, you’d use it to put on a glass cloth patch.

thank you for the response. I will research and check it out. really hope i can get everything taking care of. Do not have the budget for another kayak right now

Can you get at the crack from inside
the boat? If so, there is a cheap, long-lasting fix called Whaley welding. Successive layers of duct tape are applied with a hot iron, and then pressed more firmly in place with the convex surface of a spoon. If you can get at the inside, I will dig up the reference.

Plastic welding would be great if you have someone with a hot hand, or if you develop the knack yourself. Get a poly garbage can lid and practice.

G-flex may work without added glass, if the cracked area will not be under high stress. The technique(s) are shown on West Epoxy’s technical pdfs. They would trench the outside of the crack to make room and to assure the epoxy can grab both sides of the crack. Then they use a propane torch to briefly flame and oxidise the crack surfaces. Flaming tremendously improves bonding of epoxy to poly. G-flex is flexible enough to bend with the poly, unlike most epoxies.

My WW friends
fix kayaks by covering the crack with duct tape and hitting it with a torch.

cheap permanent fix
Eastman 5200 will stick and permanently adhere a patch to your boat.

Years ago my idiot son tied a canoe to a dock over night. In the morning it had worn a large hole in the boat. I glued (technically it is a sealant)a patch on, it was still there 12 years later when I sold the boat for $5. (the gunnels had started to rot; $5 was a fair price.)

yes I can get to it inside. Would you do the ductape only inside and not out? how many layers?

you can check this video out

G Flex epoxy will work on polyethylene boats but the surface preparation is critical. If you use G flex you need to gutter out the crack and bevel or round off the edges. The polyethylene must be carefully pretreated by oxidizing the surface by passing the inner blue cone of a handheld propane torch flame over the surface of the plastic and the tip of the blue cone must touch every square centimeter of plastic that you want to bond to.

Ideally the crack should be filled in first with G Flex moderately thickened with something like colloidal silica gel then the repair backed up on the inside of the hull with some type of fabric (fiberglass or aramid).

If you take care in prepping the surface G Flex will repair the crack and bind cloth to the hull just fine.

Maybe 8 would be enough. Let me look
for the link to the description.

It also may be advisable to take a small drill bit, perhaps 1/16, and drill right at the crack ends. This makes it harder for the crack to expand or “travel.”

I think I can handle doing that myself. I ordered a weld kit with some hobie rods. If I try it myself and fail will a professional have problems getting it back to working order?

Fixed and tested. Working 100% right now. Lets hope it holds up.

Ended up taking it down to one of the local kayak shops to ask some questions on how I was going to fix it.

They fixed it for a small fee while I was in there and showed me how to use the welder. The one they had was very similar to the one I ordered.

Now if it happens again I should be able to fix it easily.