Age versus paint on the parts versus patina, etc. I've had aluminum powdercoated when new and so far so good. I understand from the guy that did mine, not portlights, that first goes on a primer, then the powdercoat. That's all I know and a little bit more. Yes, rained all day off and on but not such a chilly wind blowing. High tides had sidewalks underwater and vaparetti on 'high tide schedule'.