Repairing a hole in a royalex conoe.
The following pictures are of an Old Town Loon 138 kayak that came off a car at 110kph when the roof rack failed. One of the cross bars went right through the side of the kayak below the waterline. This never would have happened if the kayak was tied at the nose and tail as well as secured to the roof rack. It is important to know how to transport your boat, then you won't have to ever learn this boat fixing skill. That said, you may encounter other incidents that may cause this type of damage. Falling trees, automobile accidents, there are a number of ways your boat could sustain damage. Almost all are fixable in some way. (No one was harmed in this accident) There is another kayak from the same accident that is far worse off that I have to fix this summer. When I do I will post those photos as well.
The hole must be carefully cleaned of any dirt, and the edges of the hole sanded or cut back to reveal the core foam material.
The first thing to do is to mask out an area to work on, several layers of wide masking tape should do. I used 80 grit sand paper to rough up the whole area first, and then followed with 100 grit on a palm sander to smooth things out a bit better.
Sanding both sides is important because you will later apply a patch on both of those sides. Working on a kayak is infinitely harder than working on a canoe. Lucky for me I am not that big, but this is still a very hard job. Make sure to wear a dust mask and ear plugs if you are using an electric sander. the sound is amplified by many times inside a kayak and there is no ventilation.
Remove the tape and get out your Old Town Discovery/Royalex repair kit. This is a dealer only item so if you don't have an Old Town seller in your area, go to the Old Town website (www.otcanoe.com) to locate one. This kit cost me $60 Canadian, but the price will vary depending on your location.
The next thing to do is to take a propane torch on low heat, with about an inch and a half flame, and prepare the sanded area for the resin. This is called polarizing, and it is a fancy way to describe burning off impurities to allow a bond to form with the patch. No melting is occurring and the hull temperature does not rise significantly, but it is important not to touch the area once this step is complete. If you do touch the area by accident, re-sand and re-flame the area to ensure that a proper bond can be created. Remember to do both sides of the hole or crack. Inside a kayak will be very tricky.
Once the area to be patched is polarized, apply more masking tape around the area, and a plastic drop sheet if you think you may make a mess. Remember not to touch the prepared areas. This has to be done on both sides of the hole and the next step is the most difficult.
There will be detailed instructions in your kit on what to do, how to mix the resin and hardener, and how to cut the cloth to make the patch. The cloth should be cut about two inches larger than the hole on all sides ahead of time, and the second and third layers of cloth should be slightly smaller to aid flexibility. The kit provides a brush to use which works, but a small roller will do a nicer job. The resin, once mixed will harden fast so there is a small window of opportunity to do things right. Do the inside patch first and mix only enough resin to do one side at a time. Once you have three or four layers of fabric and resin on, let the inside start to dry a bit before attempting the other side. A bit tacky is the perfect time. Apply the outer patch with a second mix of resin and hardener. It is easiest to apply the patch fabric if you roll a thin layer of resin on the prepared area first. This will help to hold the fabric in place as you build up the patch layers. Rubber gloves and protection of your skin is very important as is ventilation. This product causes cancer and is very nasty. Just do not get it on you! The product also comes with a warning sheet and info on who to call if you do come into contact with it. Hopefully you wont need to use it.
Sanding starting with 100 grit paper and working up to what ever grit you feel gives you the smoothest finish is not necessary, but desirable. I thought that 220 grit was fine but you could go higher.
There are more technical ways to color the patch. You can get pigment that will match the color of your boat from the manufacturer, but a good plastic based paint will work. I used a forest green Varithane based paint that is close. I wanted to paint a big beige bandage on the side but the client preferred green.
This article was originally posted on our Forum HERE.