Even though POR-15 says it "doesn't require" to be stripped of rust before painting, you will have better results if you sandblast first.

I POR'd a frame and decided later to sandblast it and ZR it. Part of the POR are peeling off in sheets. But most of it takes 4X the work of removing regular paint with the sandblaster.

-Boyo

'48 Willys CJ-2A / '55.1 Chevy 3600 / '66 Austin-Healey 3000 / '04 Volvo wagon (parenthood!?)