I think there are a couple of items regarging the painting of wheels that most people don't understand:

1. Most if not all components that were painted in the factory were treated through a Phosphate System to clean the metal with Detergents and treat it with a phosphate coating to help inhibit rust. This process turns the metal from a bright shiny - "Raw" Steel appearance to a dull gray appearance. It also etches the metal for better paint adhesion. This is not what most of us hobbyists do when we paint parts at home. We generally prime then paint. However DuPont used to have a Product that you could treat bare steel with that would do essentially the same thing as the factory Phosphate Process. It would leave the metal dull gray and etch it for better paint adhesion.

2. The major reason you did not get the high gloss finish on the wheels was the fact that the paint was applied at a lower film build thickness and subsequently was not "Wet Out sufficiently" when sprayed to gloss up like the outer body was. This was due in part to the fact that they only got one coat of color paint, Compared to the bodies getting 2 or more coats applied wet on wet in the spray booths. The photos from the home sprayed wheels in a post above, where they used Rattle Can" paint is a great illustration of getting sufficient film thickness to get maximum gloss from the paint sprayed. You have to understand in most assembly plant applications back in the late 60's and through the 70's, those wheels were painted on a sub-assembly conveyor at the rate of about 60 jobs per hour, so as they went by they were either hand painted or had a stationary Automatic Spray application with enough paint sprayed to get color on them and be shiny, but they were not subject to the same appearance standards as the outer body of the car was. Subsequently they were not as glossy as the primed, sanded and prepped bodies were back then.

You can probably run a test at home yourself by spraying a bare metal panel with a light coat application and then spary another one with a couple of "Wet coat" applications. then take a look at the difference of the gloss when they are dry. My money is on the one with multiple wet coats having a much higher gloss that the single coat lower film build panel.

Hopefully this will shed some light on the reason the wheels did not shine or were not as glossy as the body was, even though they had the same paint used on both the body and wheels.



Bogusracer - 38 years and counting in Paint applications in an Auto Assembly Plant.