The Basics: Drills

Whether you're an avid do-it-yourselfer or simply need a basic tool to tackle the occasional home repair, a power drill/driver is one of the most practical, versatile and easy-to-use-tools you can buy. Unlike their predecessors of the past, today's drills offer multifunction power in a more compact and lightweight design. And thanks to the cordless advantage, these tools are more convenient to use than ever before as they can be used anywhere and anytime. Depending on the drill and the attachment, a power drill can drill holes into wood, plastic, metal and concrete; drive screws or bolts; or even be used to sand, saw or mix paint.

Power drills come in different sizes relating to the size of the chuck. The smallest size is a 1/4 inch, which is typically the least expensive and most limited in its range of drilling options. The most popular size is a 3/8 inch, which means the drill can accommodate up to a 3/8-inch diameter bit. A 1/2-inch model can drill a larger hole than a 3/8-inch drill and is better suited to more heavy-duty jobs.

Drills are powered by one of two sources: electricity for a corded electric drill, or a rechargeable battery pack for a cordless drill.

A corded electric drill is measured in amps, with higher amps delivering more power. This type of drill can operate only when plugged into a standard household electric outlet. The upside is that the power time is unlimited. You can use the drill for an indefinite period of time since an outlet provides you with a constant supply of electricity -- barring a power outage, of course. The downside is that a cord can get in the way of the job at hand, and the drill's portability is limited to the location of an electric outlet and the length of its cord or length of the heavy-duty extension cord the drill is plugged into.

Cordless drills are available in a wide range of volts, from 9.6-volt to 36-volt tools. Models with a higher voltage can tackle tougher jobs -- even outperforming their corded counterparts. Since the drill is powered by a portable battery pack, the upside is that it can go wherever you go. The downside is that the battery has a limited run time, so you need to have a backup battery charged and ready to go for continuous use.

Nowadays almost all drills have variable speeds with a reverse feature for split-second removal of screws or backing a drill bit out of a hole. Most cordless drills also come with two batteries so you can use one while charging the other. However, there are distinctions among drills that make one better suited to a particular task than another.

For an all-around performer, a standard drill/driver can tackle most homeowner needs, with variable speeds for drilling or for more torque (twisting strength) when driving in screws. Most models come with an adjustable clutch, which changes the turning force to accommodate the density of the material so you are less likely to strip a screw head or drive a screw in too far.

An angle drill is a great option when you need to drill in places where other drills can't reach, such as inaccessible corners or between studs. A hammer drill does everything a drill/driver can do and is the tool of choice for masonry and concrete work due to its hammering action in the drilling rotation. Impact drivers are similar to standard drill/drivers except they have more speed and an internal hammering action that delivers plenty of rotational torque. This type of drill is especially suited to fastening screws, nuts and bolts overhead or in tight spaces or for applications involving repetitive driving.

How to Shop

There was a time when a chuck was loosened by a key, but these days most drills have a keyless chuck that allows you to quickly and easily change bits by loosening or tightening the chuck shaft collar by hand. You want to be sure that the model you select has a chuck that keeps a good grip on the bit so there is no possibility for slippage.

A smart charger is a feature that allows you to see exactly how charging is progressing. Once the battery is fully charged, a smart charger will turn itself off to keep the battery from being overcharged. Added features such as fan cooling or trickle-charge mode make the battery last longer.

Another feature fairly new to the drill market is the compact lithium-ion battery, which delivers more power with less weight. Lithium batteries also have a longer run time and a longer life than conventional batteries such as nickel-cadmium (NiCad) or nickel-metal-hydride (NiMH). Lithium-ion batteries hold a charge for up to 18 months compared to around four months for a NiCad battery.

Drills can range in price from $40 to $400, depending on the power, features and quality of the drill. To help narrow down your options, ask yourself these five key questions.

How will you use the drill?
Are you planning to build a deck, drive bolts into masonry or simply use the drill for the occasional decorating task or occasional household repair job? How often will you be using the drill? The frequency, type of work and material you will be working with will determine your drill needs.

How much power do you need?
If you're shopping for a corded drill, remember that they are measured in amps -- the higher the amperage, the more powerful the drill. Cordless drills are measured in volts, with higher-voltage models usually delivering more power. Drills in the 9-volt to 12-volt range can handle lighter weight jobs and most household tasks. The 12-volt to 14.4-volt range generally has enough power for most jobs while still being somewhat lightweight and easy to handle. Drills in the 18-volt to 36-volt range are better choices for avid DIYers and professionals.

How does the drill feel in your hand?
An ergonomic design makes a drill more comfortable to hold, easy to use and helps to reduce fatigue. However, what feels best in your hand may not feel best for someone else. Hold the drill and make sure that the grip is a comfortable fit. Check to see that all the controls are easy to access and easy to use. For example, the adjustable chuck on one model may be harder to turn than on others.

What about the battery?
Drills equipped with today's lithium-ion batteries typically cost more than comparable drills powered by NiCad batteries. But that added expense may be well worth the cost when you consider the longer run time, longer life and the ability to hold a charge longer. For comparable volts at generally less cost, a NiCad-powered model might be a better fit. Replacing the batteries can also prove costly on some models, so ask before your buy.

What other features do you want?
Most cordless drills have a keyless chuck, an automatic brake to quickly stop the chuck, an adjustable torque clutch, reverse action and variable-speed trigger control. More powerful models usually include a second handle that attaches on the drill for better balance and control. Most drill kits come with two batteries, a charger and a carrying case. Some multi-tool kits include a circular saw or reciprocating saw and/or flashlight. Other features to consider include a smart charger, fan cooling, LED lights, belt hooks, built-in levels or drill-bit storage.

Having the right tool can make a big difference in how the job gets done as well as how satisfied you will be with the end results. Naturally your budget should play a part in how much you spend on a drill, but that cost should also correlate with the type of work you will do and the frequency of use. An inexpensive model might master the occasional home repair, but for more intense projects, heavier-duty drilling or frequent use, you may need to give spend more in order to get more performance from your drill.

When buying a drill, be sure its function matches your needs as well as the materials you will be working on. Make sure the drill feels comfortable in your hand and that all the controls are convenient and easy to use. Choose a drill equipped with a battery that best suits your needs: How long does the battery take to charge, what is the run time between charges and how long will it hold a charge. Consider purchasing a drill that comes with a drill kit -- some are a good deal when you compare the cost of buying both a drill and reciprocating saw versus a kit that offers both. Just make sure that any extra tools you purchase are ones you will really use.

Finally, be sure to check out the power drill reviews on this site. That, combined with the suggestions above, will help ensure that the drill you buy will be one of the most practical, versatile and easy-to-use-tools in your toolbox or household drawer.