OK, thanks to all of you who sent me advice on how to resurface and repaint the WAFs. If I understand well, the best thing would be to cadmium plate the WAFs, but since this is not an easy option, the next best thing seems to be to prime them. For priming, the consensus seems to be to use two parts Epoxy primer, rather than Zinc chromate primer. So, I will see what the local hardware store has to offer on that department.
To remove the rust stains on the spars, the best solution is to sand, and recoat with Epoxy. I suppose 5 minutes Epoxy will be good enough for that. Now, considering that my plane has spent most of its life by the sea, including a nasty six months episode in a harbour customs warehouse in Tunis, the WAFS are in surprisingly good shape. The paint has flaked, and there is some surface corrosion, but no trace of pitting or fretting. The holes are pretty clean, and still perfectly round. I did some advanced research on corrosion repair and treatment (meaning that I read the relevant chapter of the AC-43 13 standard ;-)). On the chapter dedicated to highly stressed steel parts, they say one should not use power tools to remove the rust, because this could cause overheating the part, and therefore ruin the original heat treatment. Luckily, for surface cleaning, I have a secret weapon: rotary Nylon brushes. Serge Vidal KR2 ZS-WEC Paris, France
