how to fill cracks in fiberglass

[Sinko]

I have a few locations on the transom of my boat that are slightly cracked or damaged where the previous owner screwed something into it. One crack is about the diameter of a nickle and slightly lifted from the surface. I would like a quick way to ensure no water enters the transom possibly causing rot. Any idea would be appreciated.

 

[saildan]

Re: how to fill cracks in fiberglass

I have a few locations on the transom of my boat that are slightly cracked or damaged where the previous owner screwed something into it. One crack is about the diameter of a nickle and slightly lifted from the surface. I would like a quick way to ensure no water enters the transom possibly causing rot. Any idea would be appreciated.

Just cracks in the gelcoat fiberglass layer?

Gelcoat Scratch Repair by Don Casey


Click on image for repair guide
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Cracks down into the structural fabric reinforced fiberglass may require grinding out a small area and building it back with fiberglass resin & cloth.

 

[Chris1956]

Re: how to fill cracks in fiberglass

Like repairing drywall, you need enough of a surface area for the repair material to stick. Gouge/sand/grind out the cracks, and fill with polyester surfacing putty. Sand smooth and touch up with tinted gelcoat or paint.