Hi, I have an older model car that was painted with no clear coat. A problem that I am having is that it is getting badly oxidized in places. I can wax the car and remove the oxidation for the most part, but within a month it is mostly back. This car never used to do this but for the past year or so this has been the issue. This has me scratching my head, is there any more permanent solution oter than wacing the car once or twice a month? Any input is appreciated!