How-To-Fix a Thermoformed Plastic Kayak

"Oh, no, oh, no, my boat is broke. " I hear this every once in a while at my job as a kayak salesperson/instructor. Hardly ever does a soft plastic boat come in with a life threatening injury. Usually some nut has been dragging their Old Town Otter over a cement driveway. Well, duh, who's gonna win? The driveway or the soft plastic?

But occasionally someone will come in with a crack in their Eddyline or Hurricane thermoformed kayak. Now these boats are tough, they're made of a laminated ABS type plastic with an acrylic overlay. They're very hard to break, and since they're pretty most people don't drag them around. But accidents happen and boats will break given the right circumstances.

Paula's pretty yellow thermoformed boat went through a small tornado-type storm, a tree limb fell on it. It had four huge cracks and some missing pieces which she had in a baggy. Kind of like the finger you take with the guy to the emergency room. All kidding aside I had to tell her that the integrity of the boat would be affected because of the extent of the damage.. She bought another with the insurance money. And gave the body to me for disposal.

But, being a curious person I checked around for ideas on what to do with it. Repair was a possibility if I used the boat for a lake and only let my 12 yr. old use it. Another idea was to recycle the plastic. Huh? Apparently this stuff is reusable. Later I'll let you know if it worked.

In the meantime another boat came in with a cracked tail. This one was slightly damaged, cracks less than 8 inches and all near the end of the boat. I knew it would be ok to repair. Here's how I did it.

First, Fiberglass cloth is available at auto parts stores in a kit for fixing plastic fenders. You can't use the resin that comes in the kit. It won't stick to the acrylics or ABS. It hardens and peels off. You need to go to Wal-Mart and buy Plastic Weld glue. It comes in a two tube gadget. You squeeze out some of the stuff and mix it together then apply it to the patch. Don't try to use 2 ton epoxy or other glues, only a methymethaculate glue will work. Work on your boat in the shade. You only get four minutes to work with this stuff once you mix it. Get some blue masking tape and wrap your finger tips. Don't bother with rubber gloves, they dissolve quickly.

Clean the boat with Dawn dish soap and a bucket of water. Dry it off then scrub it down with denatured alcohol. The stuff you use to disinfect your splinters.

Put the edges of the cracks back together as neatly as possible.

Using a 600 grit sandpaper give the cracked area a good scrubbing. This gets the surface ready to stick to the glue. Be sure to scrub an inch around the area to be fixed.

Lay out you piece of fiberglass cloth and trim it to fit the crack, allowing an inch all the way around the edges.

Lay out a piece of waxed paper and put the cloth on it.

Squeeze out a big glob of the two parts of the glue. Mix it quickly but thoroughly.

Spread some of it on the cloth with a tongue depressor or something, smoosh it into the fibers.

Turn the patch over onto the crack and press down firmly.

Quickly spread the rest of the glue into the patch, pressing it into the fibers, being sure to get the edge fibers smooth. Don't overwork this.

Keep it clean and neat but don't try to redo the patch stuff.

You can try to lay wax paper over the still soft glue and mush it down to smooth it out more but usually it's already started to set.

Leave it to dry and harden, go away, don't mess with it!!

Some people advise putting another fiberglass layer on to insure that the boat is structurally sound. Do this after the first patch is set well. Good idea with big cracks in the middle of the boat but little cracks probably won't need it.

Next day pull off the waxed paper, inspect the mess and moan. Then start sanding it.

With patience you can get a nice neat looking patch. Just sand it with a 250 sand paper then a 400 then a 600. Not wet sanding.

At this point you can get some acrylic paint meant for outside art work and touch up the patch to match your boat

Or you can look for Krylon brand Fusion paint. This stuff is in a spray can, used for painting plastic patio furniture and it matches exactly the white color of the boat bottom.

Spray light coats, go over it several times as each coat dries.

Voila, you're done.

What makes the difference in your repair job is your patience and ability to work quickly. If the damage is too big don't attempt to repair it. Cracks that go half away around the boat won't be a good fix. You don't want a boat to fall apart in the water when you're using it. But small 6 to 8 inch cracks can be repaired and made structurally sound.