Cordless Drill Features
As you sort through the available options, keep in mind the old saying: "You aren't buying a drill, you're buying a hole." So answer the following before making your selection: How often will you use the drill? How wide and how deep do you want the holes to be? What kind of materials will you be drilling into? What size screws will you be driving, and into which materials? How much power do you need to make all this happen?
A cordless drill's size is denoted by the largest size bit it can hold; the bit is held in place and rotated by the chuck. Cheap cordless drills that are useful for a variety of home maintenance chores and DIY projects come in two standard sizes: 3/8" and 1/2", and the specs will say something like 3/8" chuck or 1/2" chuck.
Most 12V cordless drills, like the Ryobi HJP002 Compact Drill
(starting at $79), Porter-Cable PCL120DDC-2 Cordless Compact
(starting at $90), and SKIL 2240-01
(starting at $51), come with a 3/8" chuck. Larger 18V cordless drills and 19.2V cordless drills, like the Craftsman 17310 C3
(starting at $100) and Ryobi P815 Lithium-Ion Compact Drill
(starting at $150), typically come with a 1/2" chuck. The PowerGlide 2186955
(starting at $41) features an odd combination of small 3/8" chuck and powerful 19.2V battery.
Older drills need a type of key to unlock the chuck to change the bits. Newer models, including all the cordless drills we researched, are keyless -- you can open and close the chuck with your free hand, or, depending on the model, with the handle trigger. Occasionally the chuck on a cheap drill wears out; eHow provides instructions for replacing the chuck instead of buying a new drill.
The denser the material you're drilling or driving into, the more power you'll need. Higher voltage drills generally produce more torque. So, if you need to drill one medium-sized hole or drive a lot of little screws in material like drywall, a small 12V cordless drill like the Porter-Cable PCL120DDC-2 or Ryobi HJP002K should do the trick; the Bosch PS21-2A Pocket Driver
(starting at $105) also works well for quick and easy jobs. But if you're building a deck or a tree house, you'd be better off with a more powerful drill. An inexpensive 14.4V or 16V cordless model might suffice, but most knowledgeable DIY-ers turn to 18V drills like the Ryobi P815, Craftsman 17310, or Hitachi DS18VF3
(starting at $116).