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How Power Drills Work

Using a Power Drill

While power drills have made easy work of boring holes or driving screws, getting it just right can be a bit tricky. By following a few simple steps, you can get quality results on the first try.

With both drilling and screwdriving, the hard part is getting started. Drill bits, especially larger twist bits, have a tendency to wander across the surface of the material when you first start boring. To ensure a precise entry point, first draw cross lines to indicate where you want to drill the hole. Then use a punch -- a small tool used to stamp or pierce objects -- to create a dimple at the intersection of the lines; this will keep your bit in one place as you begin to spin the shaft. Start slowly, then speed up the drill as the hole gets deeper.

Screws have a similar tendency to wander at first. Tapping them in place with a hammer or drilling a small pilot hole before driving them in can help to ensure accuracy. When you're ready to drill, adjust your clutch setting depending on the density of the wood; a high torque setting can cause the screw head to sink in too far or break off completely. If you're loosening or removing screws, a drill's reverse function can be particularly helpful.

While power drills are simple, easy-to-use tools, this doesn't mean that they can't be dangerous if operated improperly. Most manufacturers recommend using eye protection when operating the drill and keeping your hair, clothing, gloves and jewelry away from the drill's moving parts. To prevent fire and electric shock, pay attention to the electrical power source. Inspect cords for damage regularly, and check any replacement batteries to ensure compatibility with the drill and charger. Don't operate corded or cordless drills in the rain or snow.

As with any machine, your drill will last longer if you maintain it well. Most manufacturers recommend using clean cloths to remove dirt, dust, oil, and grease from the drill, while keeping it away from commercial solvents and petroleum-based products, which may damage the plastic casing. Store fully-charged batteries at room temperature, and charge them every month or two when you're not using them. While all batteries eventually wear out, these steps will help lengthen their life.

With so many features and accessories, how do you find the drill that's right for you?