I''ve noticed the liners in some boats "weep" with the same discolored "sap" with a vinegar odor that comes from gelcoat and glass blisters. It comes out a tiny bit occassionally around the solid salon ports in my cabin top (inside). I assume it''s leaching from the cut area in the glass where the port frame mounts. Yesterday I de-blistered a 39'' Jeanneau with grinder and dremel. It was 90% gelcoat blisters that had been West-Systemed over about 4 years ago. I don''t believe we''d ever stop it without fully removing the gelcoat, which would suck. Here''s a question, though: if I fill the dimples with west filler, sand, fair and THEN barrier coat (after de-blushing) can I do one more fairing with the soft West filler OVER the barrier coat and then barrier coat again? The barrier coat is the 2-part epoxy gray stuff (by Petit?). KW
12-23-2001 06:50 AM
Use oxalic acid; available in a hardware or paint store. If that doesnt do it, then use an axe. If you compound and seal the gelcoat surface with wax (with a high speed power buffer) this wont happen. Unprotected gelcoat is porous and subject to deep staining and rapid oxidation - you should use wax to seal it. ;-)
12-22-2001 08:49 PM
I have a number of sap stains on my fibre glass top side. Nothing I have tried seems to remove them. Has anybody has success in removing these sorts of stains?