Wing skin corrosion

[Son_of_X]

One other thing to note is graphite is also corrosive to aluminum especially in the presence of salty air. Pencil marks. Not everyone knows not to use pencils to mark aluminum.

Another potential graphite contamination area is the guide blocks on your bandsaw for cutting aluminum pieces. Many people replace the guide blocks with graphite versions now. But that will possibly generate a fair bit of fine graphite dust all over everything you cut. I replaced my saw guides with some ceramic units made by a company in Montana.

And one not so obvious, pressure treated lumber. When in contact with aluminum, will cause corrosion. I had an aluminum trailer once. It had a front wheel chock for a motorcycle bolted to the front deck platform. But it needed support underneath the aluminum trailer deck for the chock. I used some pressure treated scrap 2x4 I had laying around. Bad choice. Noticed all the white corrosion about a year later underneath.