Painting a hopper bottom

Bought a 42’ sow belly Timpte, from out in Kansas. Went and picked it up last weekend and when I got it back I started cleaning. Acidized it, removed the wheels, cleaned and polished the outsides. It had Freightliner style aluminums on the outside and 10 hole aluminums on the inside, so I swapped them around to match the truck. Sanding and polishing them was very tough but didn’t turn out as good as I’d like. Mounted 8 new tires and now starting the painting prep.

 

The paint that’s existing is thin but no cracks, peeling or chips. I’ve lightly went over most of it with scotch bright and where the reflective stickers were, are a PITA. I used reducer, a razor blade, then a DA sander. I followed that with a heavy coat of etching primer. Here’s some pic of the trailer after cleaned but before the paint prep.

 

I’ll post some more tomorrow. Don’t hold me to a high standard cause I’m not much a painter and it’s my first time painting an aluminum hopper trailer.

 

Got one side painted and painted the other but not satisfied so I’m going to redo it. The first side turned out pretty good but the second side has got an, “orange peel” look.

 

I’m using an enamel with hardener. 8 parts paint, 1 part reducer and a 1/4 cap full of hardener. This one side is kicking my arse and don’t know why. Cleaned and prepped both side the same. Any thoughts or advice?

 

I’m gonna sand it back down and clean it good. In the places it was originally bare aluminum, I used multiple coats of etching primer. It’s rough like this over the whole side regardless, if it was applied over the primer or original scuffed paint. Should I increase my parts of reducer?