Well, I had my eyes opened, to say the least, by what Dan Gelbart said about metal preparation prior to applying any sort of coating.
The video is called Coatings
So much for using acetone or other products as a pre-wash, but they still worked.
All of his videos are worth watching, even if not applicable to our needs.

Geoff - Sunshine making me feel alive at last!

Location: South Norfolk - Next to Suffolk