Gel Coat Crack - how to fix?

Any suggestions on how to seal a gel coat crack? Mostly from spreading than anything else - not looking to make it invisible…

See it here:

I do not think there is any damage to the hull, just the jel coat cracked (may be when I gently bumped into a pier while exiting the boat or may be it has been there all along and I had not noticed it until I took photos for a potential buyer of the boat…)


I wouldn’t worry about it
If the area doesn’t flex when you push on it, and it doesn’t sound different than other areas when you tap around the crack, then I’d guess it’s purely cosmetic.

If you really wanted to fix it anyways, you can grind out the crack with a rotary tool, widening it to about a 1/8". Mask off the area and then fill that groove with gelcoat. Fill it above the level of the hull around it. When it cures sand down the repair until you’re scuffing the masking tape. Then remove the tape and sand everything flush, progressing up to 1200 grit wet paper.

I wish I could find a boat made entirely
from gelcoat. It would be so beautiful.

Wrong forum : )

I’m only looking for suggestive advice,
preferably from General Help.

No flex
I would not bother doing all this, mostly because I do not have replacement gel coat. I read somewhere that crazy glue might work for filling the crack and preventing it from spreading, as would epoxy I suppose. May be I’ll rub a little epoxy in there…

Whoever did the gel coat on my boat did not do a very good job - it is easy to chip and crack in some areas and appears does not adhere as well to the hull everywhere as it should…

On looking at your pic, maybe you could
get some Super Glue to seep into it. But I doubt that it will grow bigger, or that there is any underlying damage worth worrying about.

In general, for damage assessment, it may help to get the boat out in strong sunlight and inspect from inside the hull or hatches. Often this will prove reassuring. Nature of gelcoat is such that it may crack when the underlying laminate is not affected.

MacNett Spider Crack glue
Really handles small cracks well. Put that into a crack on my Explorer LV a few eyars ago, holding fine.

Wonderful that there is such a product.

Thanks (n/m)

Gel Coat
If you are wanting to repair your gel coat, remember that gel doesn’t stick to gel very well. It is best to rough the surface up or better yet have the fiberglass exposed. A lot of people don’t worry about trying to fix spider or stress cracks on a composite boat unless the gel is actually pulling away from the fiberglass or kevlar. Another trick is to always make sure you have fresh gel coat and not something that has been sitting on the shelves for months.

That’s not true…
…gelcoat bonds to gelcoat just fine. I do it all the time when repairing boats. If you have bonding issues, it’s probably from surface contamination (wax, oil, silicone, etc.). Sanding and/or scraping is a normal part of the repair process, so the contamination should be removed without any special steps, but chemically cleaning the surface with lacquer thinner before sanding is a good idea.