04-07-2019, 09:12 PM
Replacing all the screws with stainless from HPM isn't all that expensive a propositions. You're looking a few hundred dollars, depending on the size of your roof, of course.
I've had good luck with steel brushing rust, then using Rust Destroyer primer from HPM. It's the red, expensive primer, $26 a spray can at HPM or $20 on Amazon. You can also get the brush-on variety, but I find the spray convenient. You have to let it dry for a few days. It's an ugly blood red, so you'll want to top coat over it. The key to actually stopping rust is to clean nearly down to bare metal, no loose stuff. THEN prime and paint so no water or salt gets in. If you just paint over loose stuff, you're doing precisely nothing.
I've had good luck with steel brushing rust, then using Rust Destroyer primer from HPM. It's the red, expensive primer, $26 a spray can at HPM or $20 on Amazon. You can also get the brush-on variety, but I find the spray convenient. You have to let it dry for a few days. It's an ugly blood red, so you'll want to top coat over it. The key to actually stopping rust is to clean nearly down to bare metal, no loose stuff. THEN prime and paint so no water or salt gets in. If you just paint over loose stuff, you're doing precisely nothing.