Tool Feature: Cordless Impact Drivers
Delivering greater torque than comparable cordless drills, these compact tools drive fasteners like nobody's business.
Impact Drivers: Your Next Cordless Tool
Your first visit to a tire shop was likely punctuated by the loud BRAP, BRAP, BRAP of a pneumatic impact wrench. Auto mechanics love those tools because they provide loads of torque without jerking the tool when the lug nuts snug up.
Now, you can enjoy similar performance from battery-powered impact drivers. Besides their compact size and high torque, you'll also love how these tools finesse softer fasteners, such as brass screws, without shearing off their heads. So should you dump your cordless drill in favor of one of these bad boys? Let's not go that far. But an impact driver in your shop nicely complements that drill. Here's what you need to know.
Two things an impact driver is not
Despite similar-sounding names, don't confuse an impact driver with these tools:
• Impact wrench. Found primarily in auto shops, this unit-- pneumatic or battery-powered-- functions like an impact driver, but has a square socket-drive instead of the 1/4" hex chuck. It provides even greater torque for driving nuts, bolts, and other large fasteners.
• Hammer drill. This tool proves almost as noisy as an impacter, but for a different reason. Internally, a small hammer delivers a punching action down the length of the bit--like tapping a screwdriver on the end of the handle--as the chuck turns. This percussive force excels at drilling holes in concrete, but offers little more driving torque than a typical drill.