Hand-held power tools are an indispensable part of the modern toolbox. Corded and cordless power drills are among the most commonly purchased power tools. Combine with the right drill bit and you’ll have a powerful and versatile tool for home improvement projects. Here are some tips on buying a drill.
Any tool should feel like an extension of your hand. The tool may feel great while you’re holding it the store, but imagine what it will feel like after a few hours of use. Make sure the controls are convenient, and check to see if the forward / reverse and high / low speed switches are easy to use.
Drills come in three distinct handle styles. The most popular cordless models have the T-handle style where the handle is placed near the middle. The T-handle style distributes the weight for better balance and less wrist strain. Some people still prefer the more traditional pistol-grip style usually found on corded models. The third style is the right-angle version, designed for use where space is restricted.
Measuring Drill Power
Cordless drills are measured in volts. Drills are available in everything from around 2 volts (for a cordless screwdriver) to 20-volt tools. Higher voltage means heavier weight, so consider buying a tool that will meet 80% to 90% of your needs. Twelve- to 18-volt models are the most popular, and they'll usually meet most homeowner's work needs.
Corded drills are measured in amps. Generally, a higher amperage motor means more power.
Always follow the device manufacturer's operating, maintenance and safety instructions.
Choosing a Drill based on Application
Drilling softwood, hardwood, metal and masonry all require different drill speeds. Harder materials or larger bits have to be worked at lower speeds. Conversely, softer materials and smaller bits can be used at higher speeds. Look for a drill with variable speed. Variable speed allows the user to control the bit speed, which is indispensable when you plan on working different materials and accessories.
Adjustable clutch settings are a valuable feature. The clutch reacts to the resistance of the screw, which changes as the density of the material changes, allowing you to drill holes of consistent depths. Adjusted properly on identical scrap material, a clutch can keep you from driving a screw too deep, which makes this feature indispensable for beginners. An adjustable clutch can also reduce the possibility of stripping a screw head or snapping a screw off altogether.
The chuck is the attachment where the bit is inserted, having jaws that grip the bit. Drills come in 1/4-inch, 3/8-inch and 1/2-inch sizes. This measurement is the chuck size and indicates the shaft diameter of the bits and accessories that will fit the drill. (For most homeowners, a 3/8-inch size should be sufficient).
Chucks can be keyed (the jaws are tightened or loosened with a key) or keyless (the chuck can be tightened or loosened by hand). Keyless chucks offer two major benefits. If you've ever misplaced or lost a chuck key, you already know one of them. A keyless chuck will also allow bits to be changed more quickly. That's a real plus when you need to change from a drill bit to a screwdriver bit repeatedly or if you happen to be wearing gloves on the job.
You can change the chuck in some keyless models with only one hand because the shaft locks when the trigger is off. In most models, however, you have to use both hands to turn the chuck in opposite directions.
Cordless Drill Batteries
The two main cordless battery types are nickel cadmium (NiCd or Ni-Cad) or lithium ion (Li-Ion). NiCd has a longer history and is compatible with the majority of existing battery chargers. Li-ion batteries are lighter and smaller. Voltage is the best measurement of tool power, rather than battery type.
Battery charge time is affected by factors such as temperature, the material being drilled, whether the drilling is nonstop or intermittent and whether the battery is at full charge or not. Make sure you purchase a charger if one isn’t included with the tool.
The standard time required to charge a battery pack will vary from one hour to overnight, depending on the type of tool and charger. If your workload is constant, having one or more additional batteries is a good idea. Read the instruction manual for specific run-time and recharging information.
Corded drills don't depend on batteries for power. Their constant supply of electricity makes them well-suited for tough jobs, like drilling in masonry or boring large holes in wood. A corded drill requires a suitable extension cord. Follow the device manufacturer's recommendations for compatible extension cords and see Power Cord Safety Tips.
Other Drill Features
A reversible drill is a must if you plan on using the drill with screwdriver bits.
Torque is the term used to describe the rotational force exerted by the drill. Today's higher-voltage cordless drills will provide nearly the same amount of torque as a corded model. Yes, bigger is better, but increased power almost always brings increased size and weight. Unless you plan on drilling with large self-feeding or auger bits, consider a more compact model with a lower torque.
Motor technology is also important. Certain brands offer brushless motors. These types of tools eliminate the need for carbon brushes and instead are controlled via microprocessor chip. This higher efficiency design results in up to 50% longer battery run time between charges, increased power and extended durability with essentially no maintenance. These tools tend to be lighter, quieter and more powerful.
Added drill features such as built in LED lights and levels make drilling tasks a lot simple. For heaver work, reversible side handles provide more stability and control.
Accessories for drills include bits for drilling wood, metal, ceramic, glass and masonry. In addition to bits other accessories include hole saws, screwdriver bits, files, rasps and sanders.
For gift-giving, consider an all-inclusive drill set with attachments and carrying case. There are numerous combo kits offering a variety of tool options.
More Ways to Drill or Drive
To complete your drilling arsenal, add a screwdriver, impact driver, hammer drill or drill press.
Powered screwdrivers are available specifically for drywall/decking or simple for household use.
Impact driver are great for small or tight spaces. These tools are a bit` louder than a regular drill, but drive a lot of screws a lot faster.
Hammer Drills combine the rotation of a regular drill with a pounding action. These two actions enable the hammer drill to bore holes in masonry quickly without burning the bit.
A drill press is an essential tool for drilling precisely spaced holes or boring to exact depths. With the right set-up you can bore at almost any angle without fear of the drill bit walking or reaming the hole out of round. With the right attachments, a drill press can also serve as a spindle sander, mortise machine or a pocket hole machine. Given their versatility and relatively low cost, a drill press is an excellent investment for most any shop. Drill presses are available in bench-top or free-standing models.
Always unplug corded power tools and disconnect the battery on cordless power tools when servicing them.