Deformed plastic kayak.

Improper storage or transportation of a plastic boat can potentially distort the shape of the hull on your boat. If your kayak does become the victim of slight distortion, correction is a simple process. Brief exposure to the heat of the sun is often all it takes to restore the hull to its original shape. If that doesn't work, the hull can usually be restored by applying heat to the outside of the boat with a hair dryer or other low-heat source such as a 75-watt light bulb. When the hull is pliable enough, it can be pushed back in shape by hand. Be careful not to overheat the hull as you might get burned or damage the hull. A weight can be placed inside the boat against the warped area to help maintain the shape of the hull as it cools. Although cooling normally occurs quickly, we recommend that you allow up to 24 hours to ensure that the process is completed. A kayak that is used in normal conditions will receive scratches, especially on the bottom of the hull. Scratches do not alter the boat's structural integrity or navigational capabilities and should be of no concern.

http://www.roscocanoes.com.au/FAQ%60...anual-243.aspx


Plastic Kayaks.
Scratches are impossible to remove from polyethylene by sanding and polishing. If the hull is deeply gouged or punctured, it will have to be welded with polyethylene. In such a case, we recommend that you contact us for advice.

If a plastic kayak has become deformed, place it in direct sunlight for a few days. Polyethylene is a memory compound that tends to return to its original shape. The gentle heat from the sunshine will likely soften to material and help the plastic return to its manufactured shape.

However, if this process is not successful, it may be because the deformation has been present for too long a time. The following procedure will need to be followed:

1. Place the kayak upright on foam blocks positioned about 1/3 of the length of the kayak between the bow and stern. The blocks should follow the hull contours as much as possible. The blocks should each have a contact area of about 6 inches.
2. Pour about 5 gallons of very hot water in through the cockpit opening.
3. Leave for about 10 minutes.
4. Then press out the bumps or deformations in the hull with your hands. If necessary to access to the bumps, remove the seat.
5. Leave the water in the kayak for about two hours in order for it to press down on the hull. Then carefully drain the kayak.