I've glassed my Tiki21 several years ago, when for various reasons I stopped working on him. It was on dry and dark place to protect the epoxy coating from UV.
Now I've wanted to continue working on it and after cleaning I saw some black spots UNDER the epoxy glass coat. It is on outer hull skin. Couple of them, on area not bigger then fist.
The boat was never wet, plywood was dry, it was built under the roof, so I can't imagine what would cause these black spots (they seem to be in rowing squares).
Any ideas? Should I go ahaed and not worry? Or sand all the epoxy over black spots and patch thing up?
Next stage is sanding before adding filler coat.
Thanks very much for help
Edit on 5.12.2012.
I've sanded a small area to see what happens - dots are not on plywood, just in rowing. Spots dissapear befor I reach the plywood material. I've added some more photos to see.
Advice on proceeding activities welcome.