Hi guys,
I checked the keyboard of my old CPC 6128.
The metal plate has rust on both sides:
(https://i.imgur.com/Be0kwRT.jpg)
Any idea how to remove it and protect it for the future?
If you are really fussy you could use something like Phosphoric acid to stabalise the rust, then spray with a zinc primer. Personally it doens't look too bad and if you are keeping it inside the house it won't get any worse.