c/concrete-finishers

Shoutout to the guy who showed me how to use a magnesium float right

I've been finishing concrete for about 8 years now and always thought magnesium floats were just for smoothing out bumps. Last month on a job in a new development near a creek, an old timer named Rick watched me fighting with a steel trowel on a slab that was setting too fast. He handed me his worn down mag float and said just use this with barely any pressure. I was skeptical because I'd tried mag floats before and they left lines everywhere. But he showed me the angle and the speed, and I swear the cream came up perfect without tearing the surface. The slab looked way better than anything I'd done with a steel trowel on that kind of weather. Now I'm wondering how many other basic tools I've been using wrong this whole time. Anyone else had a veteran finisher show you a trick that totally changed how you work?

Just realized a wet rag on fresh concrete in summer saves so much hassle

I finally tried wet curing a driveway slab here in Phoenix

Did a residential driveway last month, about 600 square feet, and decided to wet cure it with burlap and sprinklers for 7 days. I figured the extra effort would be worth it since it's so dry out here. Ended up with almost zero cracking after 30 days, which is way better than the usual hairline cracks I see on other jobs. Has anyone else experimented with wet curing in hot climates and gotten different results?

Am I the only one who hates these new fiberglass finishing tools?

I picked up a set of those expensive fiberglass hand floats last month at a supply house in Denver. The guy at the counter swore they'd last forever and never rust. Well three jobs later and the edges are already chipping off and leaving little glass strands in my finish. Had to go back over a whole 30 yard driveway with a steel float just to smooth out the marks. My old magnesium float that I've had for 8 years still works perfect. These new materials companies keep pushing feel like they're solving problems nobody actually had. Anyone else run into this with fiberglass tools or am I just getting bad ones?

Hit my 500th pour on a driveway yesterday and it changed my mind about color matching

I've always been the guy who says just match the batch and move on. But after 500 pours over 8 years, I finally had one go bad on a big stamped patio in Phoenix. The homeowner pointed out the shade difference before I even finished. Now I mix all batches together in a wheelbarrow before pouring any of it. Keeps the color dead even. Has anyone else had a problem with batch variation on bigger jobs?

Hit 500 yards of sidewalk in one pour last month, didnt think we could do it

Me and my crew usually cap out around 300 yards for a single day. But this job was a straight run with no corners or steps, just a long stretch for a new subdivision in Hoover. We prepped everything the night before, had the mixer timed perfectly, and ran a 5 man crew with two finishers. Finished by 2pm and it all held up flat. Has anyone else pushed their crew past a number that surprised you? Id like to know what your max is before things go sideways.

Poured a stamped patio last Tuesday, still can't decide if the integral color was better than the color hardener I usually use

Job was out in Scottsdale, about 400 square feet. I've always done color hardener for stamped work, gives me that deep color I want. But the homeowner wanted integral color mixed in the truck, said it fades more evenly over time. I went with his call since it's his house. The color looks good, but it seemed to fade a little during the pour, I had to work fast. Has anyone else switched from hardener to integral and regretted it or been happy?

Got a tip from an old timer at the job site last Tuesday that saved my butt

He said to wet the subgrade an hour before you pour in hot weather, and it stopped the edges from drying out too fast on that 95 degree day. Has anyone else tried this trick with a spray nozzle vs just a hose?

Vent: Power trowel vs hand finishing on a 40 yard pour

Last month I bid a warehouse floor. 3000 square feet of slab, 6 inch thick. Thought I'd save a few bucks and do it by hand with my crew of three. We were out there for 12 hours straight, backs screaming, joints not nearly as flat as I wanted. This week I did a similar job and rented a power trowel. Night and day. Flatter finish, half the time, way less heavy lifting. Never going back. Has anyone else switched to power trowels and regretted buying a cheap one?

Tried a power trowel on a big warehouse slab in Tampa last month and now I'm spoiled

My old crew always hand finished everything because the boss said power trowels leave swirls, but this guy let me use his for a 40,000 square foot floor and it came out flat as glass in half the time. Has anyone else switched over and never looked back?

Spotted a cool broom finish at a park in St. Louis last weekend

I was walking my kid at Forest Park and saw this huge stamped concrete pathway that had a broom finish so smooth and even, it made me stop and run my hand over it (kind of embarrassing, honestly). Has anyone else ever found themselves inspecting random concrete jobs when you're supposed to be relaxing?

Warning: I think we're overthinking broom finishes on residential driveways

I keep seeing guys out here doing these super tight broom finishes on driveways in our area, like they're trying to make it look like a piece of fabric. But I worked a job last spring next to a guy who just did a light drag with a cheap push broom, and six months later his driveway had way less cracking than the one I did with all that careful combing. Is the tight finish actually causing more stress points or am I just missing something? Anyone got a concrete reason to keep doing it the hard way?

Had a builder tear into my broom finish last summer - he was right

I was finishing a driveway in June over in Oakdale and this older builder walked by during my final pass. He watched for a minute and then said my broom lines were too deep and uneven, that I was pushing the broom too hard on the wet spots. I got defensive at first because I've been doing this for 7 years and thought I knew better. But I stepped back and looked at it from his angle and honestly the texture looked rough in sections where I had rushed. So I changed my approach on the next job - started using a wider broom with softer bristles and I time my passes way more carefully now. The finish comes out way more consistent and I don't have those random deep gouges anymore. Has anyone else had a random critique from someone that actually improved their work?

That old concrete guy who yelled at me for using too much water

I was on a driveway pour last Tuesday in Austin and this older finisher named Ray came over from the next job site. He watched me mix a batch and told me straight up, 'you're drowning the mix, it's gonna dust in six months.' Honestly, he was right, I was adding extra water cause it was hot out but he showed me how using a spray mist instead changes everything. Has anyone else had a veteran just walk up and call them out on something basic like that?

Pro tip: tracked the cure time on my last slab and learned the hard way 28 days is not the same as 7.

I checked the PSI data from a local supplier's spec sheet and was stunned to see the strength gain curve barely moves after day 14, so why do we still tell homeowners to wait a full month before parking on it?

Just realized hand troweling vs power troweling on garage floors is night and day

I did a 2 car slab in Phoenix last week using just a hand trowel like I always did, took me damn near 6 hours to finish it smooth. Buddy talked me into renting a power trowel for a similar job yesterday and I got it done in under 2 hours with way less joint lines. Has anyone else fought the switch from hand to power and regretted waiting so long?

Had a long talk with an old timer in Atlanta last weekend

Was finishing up a driveway in the Buckhead area and this retired guy named Roy came over just to watch. He saw me using a power trowel and asked why I didn't hand finish more. Said he learned from his dad in the 60s that hand troweling gave better control for even light catches. Got me wondering if I rely too much on machines for flat work. Any of you still do big pours by hand or is that just nostalgia talking?

Went back to a 2x4 screed after using a power one for a month

I rented a power screed for a driveway apron in Nashville last week and it left a wavy surface I spent hours trying to fix. My granddad used to say a 2x4 screed with two guys who know their rhythm beats a machine every time. Anyone else find old school hand methods still give a flatter finish on smaller pours?

Added too much water to a slab on a hot day and paid for it

I was pouring a 12x16 patio in Phoenix last August and thought I was being smart by adding a little extra water to keep it workable. The mix got soupy and by the time I finished, the surface started dusting and cracking along the edges. Learned the hard way that more water just makes weaker concrete, especially when it's 110 degrees. How do you guys handle mix consistency when the weather is brutal?

Bought a $40 power trowel float plate and it gummed up in 20 minutes

I grabbed a cheap float plate off Amazon last Tuesday for a 400 square foot garage pour and the damn thing started dragging wet concrete right away. Ended up spending an extra hour hand finishing because it left grooves everywhere. Anyone got a brand of float plates that actually sheds clean on cooler pours?

Was dead set against using that spray-on bonder for old concrete...

Tried the $55 bag of SikaLatex on a busted up driveway in Phoenix last Tuesday and now I'm kicking myself for the 3 years I spent grinding and patching the hard way, anyone else have a product they ignored forever that actually works?

Had to choose between a $400 walk-behind trowel and trying to do it by hand...

Was finishing a 60 yard driveway in Austin last Tuesday. Foreman said rent the power trowel or pay for a helper. I went with the helper because I figured my arms could handle it. Big mistake after about 30 feet my forearms were shot and the finish came out uneven. Owner noticed and made us grind and reseal a section. Cost me $200 in materials and an extra day. Anyone else burn themselves trying to save a buck on a rental?

Tried a power trowel on a small patio slab and the finish came out wavy

I figured I'd speed things up on a 10x12 patio last weekend by using my power trowel instead of hand finishing. Thought it'd save time but the edges got wavy and the surface looked like a frozen lake. My foreman walked over and said 'you gotta keep it flat or it'll ride the high spots.' Learned my lesson the hard way. Any of you guys run into this when using power trowels on smaller pours?

Warning: I used to just eyeball my mix ratios until a slab failure taught me a hard lesson

For 5 years I'd just toss in extra water if the mud felt stiff, never measuring anything. Last summer a $3,000 driveway I poured in Phoenix started cracking within 3 months because I kept making it too wet. Now I use a slump cone every single batch no matter what and my callbacks have dropped to zero. Has anyone else had a mess up that forced them to change their whole routine?

Had a concrete pour go sideways on Tuesday and almost lost $700

I was finishing a driveway near Austin, plain gray mix, nothing fancy. Showed up at 6am like usual, everything looked fine. But the mix came in way too wet, like soup almost. I had to cut water and add dry mix on the fly while the driver was giving me attitude on the radio. Took two extra hours just to get it to a workable slump. By the time we finished the broom finish, the sun was beating down hard and I spent another hour fighting crust on the edges. Total nightmare. Has anyone else had a ready-mix driver mess up your whole schedule like that?