cracked fiberglass

Well the $100 yankee rebel I bought last year fell off the wall in a wind storm (yes it’s tied down now, too little to late). But in the fall it cracked about 6-8 inches on the side. the crack feathered the fiberglass on the inside too. i’m just asking for some guidance on the proper fix. do I sand it inside and out, before I lay the epoxy and glass cloth in on the inside and out? appearance is not important, it’s bannana yellow with mulitple patches from the previous owner. step by step method please. thanx!

If it were mine…
and it is just a crack and not opened up, I would just put the patch on the inside.

I would sand the whole area were the patch is going, and then a little more around the edges.

Wet out the fiberglass with West systems epoxy, (or equal) and smooth it into place. Immediately tape a piece of stiff celophane, like overhead projector film over the patch, making sure it is down nice and tight.

The next day take the film off, and assuming it is not tacky, give it another coat of epoxy, and then use the thin cover again.

Depending on how it goes, that might be enough, or you might even want a third coat.

The pros might tell you a better method, but that has always worked good for me, and I have fixed quite a few of our boats that way.

Jack L

one method

– Last Updated: Mar-02-11 9:45 AM EST –

I would put the patch on the inside and use 3 layers of fiberglass cloth (6 oz, plain weave E-Glass should be fine).

Sand the area the 'glass will cover with some 80 to 100 grit paper first, and then clean it well with isopropyl alcohol. It is best to apply the patches on a bias so that the fiberglass fibers are not aligned with the crack or with the long and short axes of the boat. Put the largest patch down first, then one a bit smaller, than one a bit smaller still.

Use a good 2-part epoxy like West Systems 105/205. If you find you have to buy more epoxy than you would care too, you could also use West Systems G-flex epoxy which can be purchased in 8 oz quantities (4 oz of resin and 4 oz of hardener) for about $15 and can be mixed 1:1 by eye, requiring no metering pumps. The G-flex is more viscous and requires a bit more work to wet out cloth than 105/205 but it has a longer pot life than the 105 resin used with the 205 hardener, so you have plenty of time. I find a small plastic squeege to be the easiest thing to use to spread the epoxy over the 'glass.

Once the weave of the cloth is completely filled with resin, which takes multiple applications of epoxy, you can feather the edges of the patches with sand paper.

If you want some additional strength, you could span the crack on the outside of the hull with a single layer of 'glass. You could paint over this with Krylon Fusion spray paint, which comes in a banana yellow color.

What I did
I have fiberglass a canoe I repaired, it had both a tear, and a “bruise”. The tear was all the way through, and on the upper edge. I repaired that with one layer of glass on the out side, and two on the inside. On the inside the first patch was smaller than the second patch over it. I then gave it a couple coats of epoxy to fill the weave. Sand first with 100 grit, clean to get the dust off, mix the epoxy(a little goes a long way), wet the area to be patched, apply the FG patch, and wet that. Let it cure. The bruise(a crack that doesn’t go all the way through) just got a patch on the inside. It really isn’t that hard to do, just get a box of gloves. You can read about the repair, and project here

I got the epoxy and fiberglass a Lowes. So far it has been trouble free. I

Thanks for all three of the above replies! That’s exactly what I needed. I’ve done bondo work on my car before, but that was just for inspection or appearance, not a canoe which needed help on the inside and outside.