"Maybe not immediately noticeable, but down the line it could affect durability."
Yeah, that's spot-on. I've seen guys crank it up to 900°F thinking they're saving time, but honestly, it's like cooking steak—hotter isn't always better. Had a buddy who swore by high temps until he revisited a job months later and found seams cracking prematurely. Keeping it around 750-800°F usually hits that sweet spot for me. Good call bringing this up, though... better safe than sorry down the road.
Totally agree with keeping it around that 750-800°F range. I've been on jobs where guys push it way past 850°F thinking they're speeding things up, but honestly, all you're doing at that point is risking damage to the membrane. TPO isn't meant to handle that kind of heat for sustained periods... you might get away with it short-term, but it'll bite you later.
Had a foreman once who insisted we crank the heat up—he swore it made the seams bond faster and stronger. Sure enough, a few months later, we got called back because the seams were lifting and cracking in spots. It was a huge headache going back to fix something that could've been avoided by just dialing the heat back a bit. Lesson learned the hard way.
Another thing I've noticed is that ambient temperature and wind conditions can really affect how your weld turns out. On hotter days, you might even need to drop below 750°F slightly since the material's already warmed up. Conversely, colder weather usually means bumping it up just a bit to compensate. And don't even get me started on windy days... you gotta pay extra attention to your speed and pressure or you'll end up with inconsistent welds.
I guess what I'm trying to say is, there's no one-size-fits-all number. Staying flexible and adjusting based on conditions seems to be the best approach. But yeah, generally speaking, if you're hitting 900°F regularly, you're probably pushing your luck.
- Agree that 900°F is pushing it, but I've seen experienced welders briefly hit around 850°F without issues, especially in colder climates.
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True, but I'd argue technique and consistent pressure matter even more than minor temp adjustments."ambient temperature and wind conditions can really affect how your weld turns out"
- Bottom line: temp guidelines are helpful, but skill and experience usually dictate the outcome.
"True, but I'd argue technique and consistent pressure matter even more than minor temp adjustments."
Yeah, gotta agree with this. Had a buddy help me weld TPO on my garage extension last fall, and we were pushing around 820°F or so. He's welded professionally before, and even though it was breezy and cool that day, his seams turned out perfect—mine, not so much. Same temp, same conditions, different technique. Skill definitely beats obsessing over exact temps, at least from what I've seen.
Good points about technique—I’ve seen guys weld TPO perfectly at lower temps like 750°F, while others crank it way up and still struggle. Sometimes it's just about finding your rhythm. Curious, did you guys use a roller or just hand pressure?
