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Electric drill a very versatile tool
Nov 19, 2004

Although hand tools may be required for certain jobs around the home, they have been primarily replaced by power tools. Power tools perform faster, more efficiently and with less effort than hand tools.  

The home do-it-yourselfer’s first power tool is invariably an electric drill, a versatile tool that with proper attachments can bore holes into virtually any building material, and can perform a myriad of additional tasks such as driving screws, grinding, sanding and polishing.

The best results are obtained by purchasing a variable-speed drill, which includes a reverse gear. Reverse is useful when retrieving wood bits out of deep holes, removing screws and reversing rotation on abrasive products to lengthen their lifespan. 

Another useful attachment is a “hole saw,” a special round saw blade that can cut perfectly round holes in wood. Hole saws come in single cup-like shapes in nests of rings. 

The variable-speed control allows you to select the best drilling speed and use a wider variety of special attachments.

The most common sizes of electric drills are one-quarter inch, three-eights inch and half inch. The largest bit shank that will fit into the chuck, which holds the drill bit, determines the size. 

Drill power varies with size and model, but typically ranges from one-fifth to a half horsepower. Although speed usually decreases with increased size, torque (turning power) increases.

Because of its high speed, the one-quarter-inch drill is good for boring small holes and for lightweight jobs. But, the three-eighths drill is a better choice for the homeowner because it can handle most household jobs.  

With more power than smaller drills, the half-inch drill can bore larger holes without overloading its motor. It turns at a lower speed, however, and is not suitable for sanding and grinding which require higher speeds. 

You can use standard twist bits for drilling holes up to an inch in diameter into metal, wood and most plastics. 

To drill into concrete, stone, brick or plaster, however, you will need special carbide-tipped masonry bits. When drilling into masonry, such as a concrete wall, it is recommended to use a special “hammer drill.” It drills like a regular drill but “hammers” at the same time. These drills are available in small hand-held units to larger units that are capable of drilling one-inch holes through a concrete basement wall. Units can be rented from most home building supply outlets.             

Special bits and accessories are available for other jobs around the house, such as brad-point bits that are ideal for woodworking as their centre points give accurate starts. Hollow spiral bits are good for boring through walls to run electrical wires.                                                                                                        

Forstner bits cut flat-bottomed holes and are good for cutting overlapping or angled holes and should be used with drill guides only. Step bits can be used to drill thin metal in place of several bits of increasing size. Spade bits bore wider holes. 

Most tools when used properly require little maintenance other than keeping them clean. When cleaning, unplug the power tool and then wipe it with a damp cloth or sponge. Never submerge a power tool into water or wipe it with solvents. If the tool’s air vents are clogged, blow out the debris with compressed air. Always follow the manufacturer’s maintenance recommendations.  

Avoid forcing a tool beyond its capacity and always use it for its intended purpose. 

Replace or sharpen any dull or damaged bits, blades or other cutters. Never use the power cord to pull the plug or to carry a tool. 

Most modern powers tools are permanently lubricated and sealed and do not require oiling. However, on a few tools you may need to oil specific parts.  

You may also be required to replace worn brushes, power cords or defective switches. Your owner’s manual indicates the proper procedure.