The hull cleanup
One of the many challenges I am facing with rebuilding my boat is how to fully remove the old coatings. Since the hull is aluminium which has been submerged in seawater for over two years, I need to clean it back to the bare metal to identify and correct any corrosion issues. And there is a lot of surfaces to deal with on an 11m catamaran!
Firstly, let’s get it out there that cleaning an aluminium boat down to bright shiny metal is normally a BAD idea. The only time you ever have a shiny alloy boat is when it is brand new, or if you get it treated with a clear protective coating like Nyalic to keep that shiny look. Otherwise, the bare metal will very soon fade to a muted grey, and that is how you should leave it.
The reason is that the non-shiny surface actually is an important protective coating of aluminium oxide. New aluminium
