Tool review: Compact Power Drivers
Just as the diminutive David slew the ferocious giant, Goliath, to the surprise of everyone, these pint-size lithium-ion powered tools blew our expectations out of the water with their staggering screw-driving abilities. In fact, since we began using them, the larger 14.4- and 18-volt drill/drivers in the WOOD® magazine shop now see primarily drilling duty as we reach for compact 10.8- and 12-volt micro-drivers almost exclusively for driving screws—especially for hinges and small hardware. Their compact size minimizes hand fatigue and provides them better access to tight quarters.
With weights ranging from 1.8 to 2.6 lbs (with battery installed), these cordless tools weigh about half as much as nickel-cadmium powered 14.4-volt drill/drivers, and even less than the bulkier 18-volt drills. They achieve this by using lighter-weight lithium-ion chemistries in their compact battery packs. Although most micro-driver manufacturers claim 12 volts of power compared to 10.8 for others, we saw no distinct advantage that could be traced to rated voltage. (One manufacturer started the trend of claiming 12 volts of power, and for competitive reasons most others followed suit.) All 10 tested units drove more than 150 15⁄8 " drywall screws into pine on a single charge, and five drivers topped the 200 mark. (By comparison, the 14.4-volt drill/drivers we tested only a few years ago drove from 217 to 522 screws per charge.)
Using new 3⁄4 " spade bits, all the tools drilled at least 19 11⁄2 "-deep holes in pine on a single charge. One driver nearly tripled that with an average of 48 holes per charge. But most struggle with bits larger than 3⁄4 " in diameter and drill slower than larger drills. Driving screws is what these tools do best, effectively making micro-drivers a bit of a luxury item for most home workshops. So if you can buy only one tool for your drilling and driving needs, get a conventional 14.4-volt or larger model.
More to consider before buying
* Charge time. Each driver comes with two batteries and a charger. All required from 30 to 60 minutes to top off, but given the run time per charge shown by most of the drivers, you'll likely not exhaust a battery before the second one is recharged.
* Chucks. Six models feature 3⁄8 " three-jaw chucks, while the others have quick-connect 1⁄4 " hex chucks, as shown below. Neither style proved a deal-breaker, unless you plan to drill much with the tool; only the three-jaw chucks accept round-shank bits.
* Clutches. All the tools sport clutches with at least 10 settings—most had 18 or more—and we found all the clutches helpful to prevent stripping out or shearing off heads of brittle drywall screws, as well as tiny brass hinge screws.
* Grip comfort and balance. Most of the drivers felt comfortable and nicely balanced. Those with three-jaw chucks proved slightly more front heavy. Battery packs on some models feature small stems, resulting in slimmer grips, as shown below. The triangular-shaped packs on the others slide into the handles, requiring thicker grips that could be uncomfortable for small hands.
Any of these micro-drivers would likely be a welcome addition to any shop. But for us, three models drove to the head of the class to share our Top Tool award: Bosch PS20-2A, Makita DF030DW, and Milwaukee 2401-22. The Makita displayed the best power, and the Milwaukee demonstrated the longest run time per battery charge. The Bosch was second-best in power and third-best in run time. All are well balanced, comfortable to grip, and feature easy-to-use clutches and hex chucks. We suggest you choose the one that feels best in your hand.
Learn the results of our testing of the Bosch PS20-2A and PS30-2A, Craftsman 11812, Hitachi DB10DL, Makita DF030DW and DF330DW, Milwaukee 2401-22 and 2410-22, Ridgid R92008, and Ryobi HJP002K in the July 2010 issue of WOOD magazine, or download the review.