The swelling and cracking in your picture sure looks like a classic case moisture having gotten to the steel backing into which the bolts are fastened. The backing, which Amel buried in the fiberglass layup during construction, then rusts and when it gets really bad the rusting metal starts to expand and bursts the fiberglass structure, along with the gelcoat.
No amount of cosmetic repair will fix this - one needs to cut the fiberglass open, remove and replace the steel and reconstruct the toe rail. You will develop excellent fiberglassing skills by the time you are done and drilling out the nylon screws will be a minor step.
I would recommend not embedding the new backing in the rebuilt fiberglass, but putting it on the underside, exposed to air, and using stainless steel (lest you have a repeat performance at some future date).
This is a common problem that has been discussed often on this forum, with trouble areas being the engine room and other hatch cover supports and hinges, stanchion bases and so on.
Optionally, just live with it for a few seasons. It will slowly get worse but won't present a structural problem nor make the eventual repair work much more difficult. Use some hydrochloric acid to wipe off the rust stains now and then, put in some cosmetic fill that will last a while and when the toe rail actually cracks open, you can tackle the repair.
Craig Briggs, SN(G&T) 68, Sangaris
---In amelyachtowners@..., <alanwood123@...> wrote :
The family and I (3 kids) are now six months into owning and living aboard our 1997 SM#189 in Lefkas, Greece and getting our teeth into lots of maintenance! First of all I'd like to thank all those who have contributed to the forums both here and on Facebook.. it's been very informative and immeasurably helpful and I fully intend to contribute my own insights/photos/videos.. when I get a moment!
So first off.. after copious amounts of rain over the last few months I noticed this swelling and cracking of the gelcoat and what looks like rust marks on the toe rail under the genoa track. The underside of this is at the back of the galley cupboard (left of the microwave).
A couple of opinions/insights please, before I go at it like a bull in a china shop:
Thanks in advance..