That's a solid suggestion about angling the sample slightly—makes sense for mimicking real-world runoff. I'd also recommend placing a small piece of untreated wood or plastic underneath to keep it off direct ground contact. In my experience, moisture from grass or dirt can skew results because it traps humidity way longer than you'd expect. Learned that the hard way after a week of unexpected rust spots...
Good call on keeping it elevated—I had a similar issue when testing some metal flashing. Thought I'd be clever and just propped it up on bricks, but the bricks themselves absorbed moisture and threw off my results. Ended up using plastic spacers instead. Curious though, are you planning to test different coatings or just checking how the bare metal holds up over time?
Good point about the bricks absorbing moisture—seen that happen plenty of times myself. Plastic spacers are solid, but I've also had good luck using short sections of PVC pipe cut into rings. Cheap, easy to find, and zero moisture issues. As for coatings, bare metal testing is useful as a baseline, but adding a few coated samples (galvanized vs painted vs bare) can really highlight performance differences over time. Might be worth considering if you're already set up for it...
PVC rings are a clever idea—wish I'd thought of that before messing around with scraps of wood. Learned that lesson the hard way after a soggy winter. Definitely agree on testing different coatings; galvanized surprised me big time last year.
PVC does sound handy, but honestly, I’m still a bit skeptical about going all-in on plastics outdoors—especially after my experience with some supposedly weather-resistant stuff last year. I tried using leftover composite decking scraps for a similar project, thinking I was being clever and thrifty. Come springtime, those boards had warped and twisted worse than the wood they replaced... lesson learned the hard way.
Funny you mention galvanized coatings surprising you—I had pretty much given up on them after seeing rust spots pop up on some cheap galvanized brackets I bought. Maybe it just depends on quality or prep work? Either way, I'm definitely starting to think testing samples first is the smart move before committing to any big DIY project.
