canoe repair

[bonnieboat]

the sun has baked this old fiberglass canoe we have to the point the gelcoat?? or exterior has cracked and small pieces have fallen off. i was hoping to sand it,and fill in any spots or cracks with just the resin. anybody have any good ideas ???

[Prof]

Hi Tony,

Let me try this again. Apparently I took too long to compose my comment and the site made me sign back in when I tried to submit. After signing back in, my reply was lost! Second time a charm?

Anyway, a few years ago my neighbor ended up with a couple of holes in his fiberglass canoe. One was fairly small and the other fairly large (4 x7 inches) with a number of spider cracks radiating from the hole. After cutting out the loose stuff, I sanded down the edges to firm material, tapering back the edges on both sides. I also sanded a wide tapered groove along each crack down through the gel-coat and into the glass.

I then laid several layers of glass (with resin) covering each hole being careful to make each layer a little larger than the last. This stepped layering is important to avoid a weak spot. I also did the same for the cracks. The holes were covered from both sides while the cracks that only showed on one side where only addressed on that side.

After filling in a couple of low spots with thickened resin (I use micro balloons but there are lots of things that will work) I sanded everything down. Finally, after a quick paint job, you cannot see the repair unless someone pointed it out to you.

If you are looking to just fill some low spots, I think that sanding down and filling will work, but you should use thickened resin. Resin alone will run and you’ll not likely get it smooth.

Hope this helps.

John

[nickoftime]

in fibergalss cracks will usually come back unless you sand enough of the crack to increase the strength again if the cracks are big take a dremel tool with a small bit to the end of the cracks this will stop the crack from spreading farther. Also they make a thicking agent like cabosil its a fine powder that we use in the marine industry to thicken gelcoat or resin. after you prep the crack you should add fiberglass to the area to add strength. put the fiberglass on cardboard pour the resin on use a brush to get the fiberglass wet then put it on the bad area and smooth it out with the brush. make it as smooth as possible sand when dry recoat with just resin to make it smoother. good luck

[Prof]

Hey Kevin,

I like the idea of taking a Dremel tool to the end of the crack to stop it spread. While I’ve not had that problem, it seems like an extra precaution that is easy to do.

Learn something every day!

[1mainiac]

We used to use this green Fiberglass filler can't remember the name but is sort of like bondo with fiber glass mat in it and you used resin hardener with it. If all you have is surface damage you can clean it out with a grinder or dremel tool and use a filler it is much quicker and I have used the filler along with glass mat. Once you get the area prepped cut a thin peice of mat slightly larger than the repair area lay it on a sheet of alum foil mix up your resin and apply it to the mat making sure you soak it all the way thru the mat then brush a coat of resin on the repair area and apply the patch use a roller to work it in and let it setup then peel off the foil. For small repair spots shread the fiberglass mat and mix it in with you resin apply it and cover with alum foil and use a roller to smooth it out and pack it down into the area.