Heat welding is the technique used to repair deep scratches, holes, leaks and other injuries to the shell of a plastic kayak. It takes a bit of patience and focus but is not difficult to do.

Essential tools

  • Heat gun
  • Soldering iron
  • Blade or Stanley knife
  • Clean cloth
  • Metal dessert spoon or silicone spatula
  • Spare plastic pieces

The blade is used to scrape melted plastic from the point of the soldering iron. Keep the soldering iron clean or else the plastic blackens. The blade can also be used like a spatula to take melted plastic from the spare piece or the end of the soldering iron to press it into the patching site (like icing a cake).

The blade is also used to scrape over the patch once done to remove any bits and to even the surface, blending it to shell. Putting the heat gun on the patch for a short period (barely even a minute) will remove the ‘white’ by melting and give a polished finish.

Heat welding can be done to repair splits and gouges too – this takes more added plastic, more skill and patience.

If you have a serious split in the plastic, drill a hole at the top and the bottom to stop it running. Then repair.