Epoxy or grind and glass?

[jdrutten]

I’m getting ready for launch this week and found these little voids above the rudder joint. They’re very small (<5mm) but probably suggest a larger issue. I don’t think it’s connected to the transom floor but I guess I’m not real sure. Could I get away with a little thickened epoxy, or will I need to grind it out and lay in some fiberglass? I think I already know the answer but in the off chance that epoxy would work I won’t have to worry about further delay.

 

[DougM]

That looks like a void in the gelcoat that may have dated back to manufacture. Assuming that the boat has been out of the water for at least the winter, it is probably dry inside.
I don’t know if I would do the epoxy approach though. If I did, I would try Marine Tex which is more like an automotive body filler. Label says it can be used to repair surfaces that will be under water.
It doesn’t seem to be a structural, It might be better to grind back the gelcoat, fill the area with chopped fiberglass and resin. Then coat it with gelcoat.

 

[dlochner]

These types of voids are fairly common and are probably not a big deal. But they should be repaired.

The void is formed when the boat is laid up. First gelcoat is sprayed into the mold and then the glass is laid up. Glass is stiff and does not like to be formed into tight radii. When the glass is tucked in, sometimes it will pull away from the inside corner. This leaves a little void between the brittle gelcoat and the structural glass. Eventually the gel coat cracks and the void appears.

To fix it, just chip away until the void is gone and rebuild with some thickened epoxy. Use a structural filler not a fairing filler. Rebuild the area, sand fair, and bottom paint. Whatever you don't get done between now and launch can get done next fall before a freeze. Probably best to get the area dry and water free before winter.

 

[dLj]

+1 on what @dlochner said. My personal favorite epoxy for this one is West System Gflex 655.

dj

 

[jdrutten]

I'm relieved that it might be relatively minor as opposed to incurable boat cancer. I'm hoping to possibly get back out tomorrow and maybe pick at it a bit. Hopefully the underlying fiberglass doesn't look too bad.

 

[dlochner]

I'm relieved that it might be relatively minor as opposed to incurable boat cancer. I'm hoping to possibly get back out tomorrow and maybe pick at it a bit. Hopefully the underlying fiberglass doesn't look too bad.

It probably won't.

A Dremel tool with a grinding cone will open those up in no time and provide a nice surface to fill and fair.

 

[Tally Ho]

Mine looked a lot worse than that...I ground out a bit of the damaged glass, used some thickened epoxy to fill and gaps and smooth things out a bit, then laid a few strips of glass over the edge to finish it off.



Still needed some sanding and barrier cost, but she is in the water and sailing fine!

Greg