Concrete poured as dry as possible makes stronger and harder footings, stair landings, and sidewalks that are less susceptible to weathering. The chemical reaction that hardens concrete needs far less water than is needed for concrete to be worked easily. Consequently, it is often poured too wet, which results in permanently weaker concrete.

To work with a drier mix, a vibrator is almost a necessity. The vibrations spread through the concrete slurry, helping it to settle and driving out air that forms voids. This is particularly important for deck builders when the footings will extend above grade, such as on a raised deck. It’s frustrating to pull the cardboard form off a footing and find air-pocket voids where smooth, solid concrete should have been. Not only is this an aesthetic issue, but voids in the concrete surface invite water that can cause the concrete to spall during freeze and thaw cycles.

BVR450 18V LXT Lithium-Ion Cordless Concrete Vibrator Makita 800/462-5482 Street price: kit (includes 18-volt charger and two lithium-ion batteries), $490; tool only, $290

The vibrators common to concrete crews, however, are bigger than deck builders need. Enter the 18-volt Makita BVR450 cordless concrete vibrator, which is just the right size. It’s compact, at only 54 inches long (4 feet of which is the “stinger”), and weighs 8.2 pounds. This little monster produces 12,500 vpm (vibrations per minute), and its stinger will consolidate about a 6-inch radius of concrete.

What really impresses me about it is how long the battery lasts. I used a BVR450 when our church poured a 13-yard (a full concrete truck holds about 10 yards) wheel-chair ramp at a charity gig this past August. The first battery powered through about 9 yards. Even better, the battery charger plugs into the cigarette lighter of my truck. Man, is that convenient!

Contributing editor Kim Katwijk is a deck builder in Olympia, Wash.

Aftermarket Skil 77 Guard Retractor

Carpenters either love or hate the venerable Skil 77 wormdrive and its clones. It’s the standard circular saw on the West Coast, while we East Coasters tend to favor sidewinders. That said, I’ve seen more than one 77 on job sites in New England and in fact, used one myself on the last house I framed. And why not? They are considerably heavier than the sidewinders I’m more used to, but you can’t kill them, and the blade visibility is great.

Original 3rd Hand .357 SawGuard Safety Lift SJ2 Industries 760/200-3359 Street price: $30

Other than its weight, the chief downside to the 77 is that it’s configured in a way that makes it nearly impossible to hold back the guard with your left hand, as needed for angled and plunge cuts. The traditional fix for this problem is to pin the guard back, which scares the hell out of me, not to mention violating all sorts of OSHA regs.

Jack Tracy, a long-time West Coast builder, thought the same thing, so he engineered and patented the 3rd Hand .357. I tried it out at the JLC Live residential construction show last year, and it worked great. There’s a lever positioned exactly where my right thumb wants to be, and pushing it down raises an arm that pushes up on the guard to raise it. Sweet.

I ordered one up for my Skil 77. True to the literature, the 3rd Hand .357 installed in under five minutes, requiring only the removal and reinstallation of three screws. I didn’t even have to look at the instruction sheet. The screws on my 77 have Torx heads, so check that before you get your hopes up only to find you don’t have the right bits.

But then it didn’t work. Hard as I pushed on the thumb lever, nothing happened. That was a disappointment. I called up Jack, explained the problem, and told him I figured I’d done something wrong because I’m a sidewinder guy who rarely uses his 77. After Jack got done good-naturedly telling me to turn in my man card for using “sissy saws,” he suggested that I try cleaning out where the guard pivots.

I took off the blade, scraped away the solids with a screwdriver, and fired a two-second burst of carburetor cleaner behind the guard. That’s all it took, and the 3rd Hand .357 worked like, well, a third hand. If you’re a Skil 77 user, this is a great upgrade. — Andy Engel