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Serious question, has anyone else used a power trowel on a 4 inch slab before it was ready?
I was finishing a garage floor in Phoenix last week and got ahead of myself. The concrete looked set enough after about 3 hours, so I fired up the walk-behind trowel. It immediately started tearing the surface and left deep gouges. I had to stop, let it cure for another hour, and then spend twice as long hand floating to fix it. I learned you can't rush the initial set, even when the sun is beating down. What's the shortest time you've ever gotten away with before hitting it with power?
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torres.leo1mo ago
Ben's slump question is key. A low slump mix in that Phoenix heat might skin over fast but still be soft underneath. I've seen guys get fooled by a hard crust when the paste below isn't locked in. The shortest I ever made it work was just under four hours on a cool, cloudy day with a super six inch slump mix. Anything less than that and you're almost always gambling with tearing it up.
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parkermorgan7d ago
We had a pour in Tucson last summer where the finishers showed up late, like three hours after the truck.
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