Good points, but I've welded TPO midday without too much trouble—just dialed down the heat and moved quicker. Maybe membrane brand matters? Curious if anyone's noticed certain brands handle heat better than others...
"Maybe membrane brand matters?"
Definitely noticed differences myself—some brands handle heat fluctuations better. Carlisle and Firestone seem pretty forgiving even midday... but I've wrestled with cheaper membranes that got gummy fast. Guess you get what you pay for sometimes.
I've noticed the same thing about Carlisle membranes—they seem to have a wider sweet spot for heat settings. Ever tried welding on a cloudy day versus full sun? Huge difference in how quickly things get gummy. Makes me wonder if it's just brand or also thickness and color playing a role... probably a combo of all three. Either way, you're right—cheaper membranes can be a headache when temps climb.
"Ever tried welding on a cloudy day versus full sun? Huge difference in how quickly things get gummy."
Yeah, I've noticed that too... but honestly, I'm not convinced it's just the brand. Had a roll of Firestone once—same thickness as Carlisle—and it seemed to behave differently under identical conditions. Maybe it's the additives or even storage methods before installation? Curious if anyone's tracked down exactly what's causing the gummy factor.
I've definitely run into the gummy issue myself, and honestly, I'm not sure it's just about brand or additives. I remember one time we had some TPO rolls stored in a garage for a couple months before installation—same batch and everything—and the rolls that sat closer to the sunny side of the garage definitely welded differently. Maybe heat exposure during storage makes more of a difference than we realize?
"Maybe it's the additives or even storage methods before installation?"
This seems spot-on to me. I mean, even subtle differences in how they're stored or transported could probably change things up quite a bit. I don't know all the science behind it, but it feels like there's more at play than just cloudy vs sunny days. Either way, I've learned to weld early mornings or late afternoons to avoid that midday gummy mess... saves me headache and material!
