"Curious, did you apply a primer before sealing? Some skip it, but I've found it helps adhesion long-term."
Primer's definitely underrated. I remember one job where we skipped it—boss was in a hurry—and sure enough, we were back up there within a year fixing peeling sealant. Lesson learned the hard way. Speaking of prep though, anyone ever tried scuffing the metal lightly with sandpaper before priming? My mentor swears by it, says it gives the primer something extra to grip onto...
"Speaking of prep though, anyone ever tried scuffing the metal lightly with sandpaper before priming?"
Funny you mention scuffing—I actually picked that up from my dad years ago. He always said primer sticks better if the metal has a bit of "tooth" to it, and honestly, it's never let me down. Even on my shed roof, where I went kinda lazy on the sealing part, the primer held up perfectly. Guess dads (and mentors) know best sometimes...
Yeah, scuffing definitely helps. I've seen plenty of metal flashing peel or flake because someone skipped that step. Primer just doesn't bond as well to a smooth surface...a quick sanding can save you headaches down the road. Learned that one the hard way myself.
Couldn't agree more about sanding first. A couple years back, I had contractors redo some flashing around our building's rooftop HVAC units. They skipped the scuffing step—probably to save time—and within a year, the primer started peeling off in sheets. Ended up costing us extra to have it redone properly. Lesson learned: shortcuts rarely pay off, especially when dealing with metal surfaces exposed to weather...better safe than sorry.
Yeah, sanding or scuffing is definitely key, but don't overlook cleaning the metal surface thoroughly before you even start sanding. I've seen plenty of cases where folks sanded properly but skipped wiping down the metal with a good degreaser or solvent first. Any leftover oils or dirt can mess up adhesion just as badly as skipping sanding altogether. A quick wipe-down with acetone or mineral spirits usually does the trick—takes just a few minutes and saves headaches later on.
