Repairing Dents, or ‘Oil Canning’, in a Rotomolded Plastic Kayak

What is oil canning?

Rotomolded plastic kayaks will occasionally develop indentations in their hulls. This doesn’t mean the kayak is ruined nor will they even affect the performance of the boat in most cases. These dents are sometimes referred to as ‘oil canning’, because they tend to pop in and  out under pressure, similar to an oil can. The most common cause of these indentations is improper storage or transport, particularly on hot days. For example, tying a boat flat on its hull on a roof rack without padding.

Dented, or ‘oil canned’ plastic kayak

How to Fix the Dent

You will need a couple of things:  Weight or something to brace the indent out, a heat source, patience and time.

1.

The first thing you should try is putting the boat in the hot sun for a couple of hours with the dent exposed to the sun.  It may pop out and reform on its own.  Most likely you will need to push the part of the dented back out using your hands to try and pop it back in shape.  If it won’t stay in place, you may have to use weights or some kind of bracing to hold it in place while it cools down.  This can sometimes entail a bit of creativity!

Using a brace to hold the dent in place

2.

An alternative to leaving the boat in the sun is to use a heat gun, hair dryer, heat lamp or hot water. Be very careful to only heat the plastic to a soft state without burning or melting it.   This is particularly true when using a heat gun!  Be patient, it can take some time to warm up the plastic.

Prevention

The best way to deal with oil canning, is prevention. The most common way that dents form in rotomolded plastic kayaks is being tied down to roof racks for long times. However, can happen in the time it takes you to drive out to the launching spot for your trip. To prevent this, use kayak cradles for transporting your boat whenever possible or transport you boat on its side using kayak towers.   If not, use some type of padding.  This is an easy and inexpensive solution. The best pads are  the ones shaped to conform to the shape of the hull.

Kayak Cradle

Shaped Kayak Rack Foam Pads

At home, store your boat on it’s side or for shorter boats, on end – never flat on the hull.  Avoid storing kayaks on small hard surfaces without using padding, even if they are on their sides.

Good Luck and Happy Paddling!