Found a Few Hairline Cracks in the Fiberglass Siding

Just cover them with a big old wad of goo. kidding.

Thanks for the info everyone!

The cracks feel pretty superficial, so I think it's just the gel coat and not the actual fiberglass underneath. I'm going to mark them and see if they grow on this next trip before deciding how to proceed. That sealant Barney linked to looks pretty promising and is maybe all that's needed after etching the tips of the cracks to stop them from growing.

Not enough time to worry about them now - headed out camping tomorrow morning! :)

This stuff should take care of it.
Barney

Drilling is done if the crack is completley through the material such as in cracks in metal. Gel coat is a cosmetic covering on fiberglass to give it color and shine. If the crack is in gel coat the underlying fiberglass will not corrode.

These develop on almost every fiberglass vehicle or boat that flexes. On my boat, what I do is take a razor blade and etch a small circle at the tip of each gel coat stress crack. What this does is forces the crack to run back on itself. Filling in these stress cracks don't do much since its superficial. Purely cosmetic. I personally don't prefer the drill method because that becomes too invasive.

OBSPowerstroke wrote:
So what do you all think? Is there a way to repair, seal, and/or stop these cracks? Do I need to even worry about them? If they can be repaired or sealed, is it an easy do-it-yourself job or am I looking at dropping lots of cash for the dealer to repair it?

Thanks!

Cracks such as this can be repaired by doing two things - arresting the crack growth, and then filling the crack so that it is sealed and does not allow leaks through the crack depth.

To arrest the crack growth, a smooth hole is drilled at the crack tip so that the crack tip ends at the close edge of the hole (i.e the crack if it continues to run, would run into the hole), and then the crack can be filled in with epoxy. To do that you may need to gouge along the crack co that it is v-shaped through its depth. Once repaired the area can be sanded flush and then painted.

Now if the crack is only in the gel coat then the need for repair may not be as great. That would need careful examination of the actual crack.

The cracks look like they are in the gel coat. They may look unsightly, but the fiberglass underlayment will not be compromised. Basically, these gel coat cracks are cosmetic. Fiberglass boat owners have been dealing with this type of crack long before they started putting fiberglass exteriors on RV's