No matter what project your'e doing, you'll need to drill some holes and drive some screws once in a while. A lightweight drill/driver should be the first power tool that anyone owns. Here's why.
From hanging photos to assembling flat-pack IKEA furniture, the need for a drill/driver is obvious. These dual-purpose power tools can accept drill bits for drilling holes and screwdriver bits for driving slotted, Philips, square and torx head screws much faster (and more powerfully) than you could with a normal screwdriver.
Corded drills are designed only to hold drill bits and other attachments , but lack a clutch, which gives you greater control of how much torque is applied by the tool. This clutch is what separates a standard drill from a cordless drill/driver. It allows the tools motor to disengage from the bit at a preset value which will prevent it from driving a screw too deep or stripping it.
Clutch settings range from 1 to 10 or 1 to 20, with 1 disengaging with the least resistance and 10 or 20 disengaging with the most. There is also a drill setting which is identified as a drill icon. Use this setting when using the drill/driver as a drill for maximum torque and RPM. If your drill/driver has a hi-lo speed option, select low for driving screws and high for drilling.
Be mindful of the clutch setting when driving screws, as too much torque can cause the tool to twist in your wrist if it hits a lot of resistance quickly. Start with lower resistance and gradually adjust up if needed.
Located just in front of the clutch is the chuck which holds the drill bits. Chuck size refers to the maximum diameter of the bit that the drill can hold and sizes range from 1/4", 3/8", to 1/2". You want a keyless chuck which can be turned by hand. Turn it clockwise to constrict and tighten around the bit and turn it counter-clockwise to release the bit.
Beyond chuck size, cordless drill/drivers are available in a variety of power options. Lithium-Ion powered tools are powerful and lighter but more costly than Ni-Cad options. 12-volt drill/drivers will offer the most compact tool but will have the least amount of runtime and power. These are all tradeoffs that come down to personal preference.
Choose a drill/driver that fits comfortably in your hand. Take note of the tool's weight, handle size and grip surface.
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