Used to hog the power trowel on big pads, switched to letting the finishers walk it first

For about 5 years I'd jump on the power trowel as soon as the concrete was stiff enough, trying to get that perfect finish myself. But I kept getting these random lines and inconsistencies on bigger jobs like parking lots. Then about two summers ago on a 20,000 square foot slab in Denver, I watched an old-timer let his crew hand-walk the edges and corners first before he even fired up the trowel. I tried it on the next job and the finish came out way more uniform because the concrete had time to set evenly across the whole surface. Now I only get on the machine after the finishers have done their initial pass with floats. Has anyone else seen better results by holding off on the power trowel for a while?

2 comments

2 Comments

nancyd8529d ago

Nah, I've had better luck jumping on early to beat the set...

sean_martin4428d ago

The timing thing is interesting but the real game changer might be moisture. If you wait for the finishers to walk it, you can see where the slab is bleeding unevenly before you seal it with the trowel. On big pads the edges always dry faster, so jumping on early just traps that moisture in the middle. That's what causes the blotchy spots later. I started using a moisture meter before I even decide to fire up the machine, and it changed how I read the surface way more than the clock.