Oxidised Aluminium

Yep, leave it as it is, or just sand it down. Ally doesnt corrode through like iron, it gets the white rough oxide on the surface, but doesnt usually get much deeper.But on thin panels I know it does go through as they are so thin.The worst bits are where it is touching iron, and you get catalytic corrosion between the 2, this can mean new panels,or a lot of repair by rivetting on ally plates. Alan.

clean off the powered oxide and treat with etching primer that should sort it out a 15fl oz aerosol should be less than a tenner then prime and topcoat as normal Derek

Do you need to prime on top of an etch primer?

Alex

Yes - etch primer is actually very thin and doesn't give a very good finish to top-coat onto.

Tim Hobbs

'58 Series 2 '77 101FC Ambulance '95 Discovery V8i

I know that part, however there is no actual need to use a primer on top of etch.

I paint mine with a brush, so I don't bother with hi-build, rubbing down, etc etc etc. Just slap it on

Alex