I tied my kayak down on my roof rack really tight and now I have a dent in the bottom. Is there any way to correct this?

I tied my kayak down on my roof rack really tight and now I have a dent in the bottom. Is there any way to correct this?

There are a couple different options presented here to remove a dent in your kayak. 
  1. If the dent or deformation won’t push out easily, leave the kayak in the sun with a black garbage bag over the area. This should heat and soften the plastic to the point that you can easily push the dent out of the hull.  Polyethelyne plastic has a memory from being first molded, so over time time it should return to its original shape.  
  2. Heat and Pressure. Watch the following video to learn how to use a combination of heat applied to both sides of the dent and pressure outwards, gives us the result we need. With a bit of patience, hot water and a heat gun you can restore your kayak hull to it's original shape.


Here is some additional info:  
Due to the nature of plastic it may happen that a kayak will develop an indentation in the hull that we refer to as ‘oil canning.’ These indentations tend to form under pressure, either by hitting a particularly hard surface or through improper transport or storage.
The first technique to remove a dent is to place the kayak in direct sunlight (the temperature must be hot enough to soften the plastic) where the kayak will heat up and naturally reform to its original shape over the course of a few hours. Once done it should retain its proper shape.
If that does not work the process may need some additional help in the form of weights/ your hands to push the indentation back out. Again, once reformed it should retain its proper shape.
If you do not have access to natural ‘effective’ sunlight you may follow the above steps using extremely hot water or a hair dryer to achieve the softening effect needed. Please note that you will heat the plastic just until it is pliable, not to melting. A heat gun may be used for the same purpose but in inexperienced hands may do more harm than good and thus is not suggested except as a last resort. To avoid the same issue in the future please read the sections on the proper storing and transporting of kayaks.