Selecting the Right Drill for the Job

Portable Drills Safety Tips

Always use safety glasses and ear protection when using a power drill.

Double-insulated drills do not require a three-wire grounding cord and the user is protected in the event of an electrical short.

Always make sure the drill bit fits tightly into the chuck before operating the drill.

Never drill a hole that is larger than the rated capacity for the drill.

Don’t force the drill. If the drill begins to slow down, relieve the pressure so the drill bit can continue cutting smoothly. Forcing a drill can cause the motor to overheat and damage the drill bit.

If the drill binds in the material, release the trigger immediately, unplug the drill and remove the bit from the material. Never use a “lock on” feature if you are drilling in a material you suspect could cause the bit to bind. A bound up bit can cause the entire drill to rotate instead of the bit and pose a danger to the user.

Unplug the drill before changing bits.

Always have firm footing when drilling. Brace and position yourself carefully when drilling on a ladder or scaffolding.

When drilling blindly, (when you don’t know what might be behind the surface you are drilling into) always check for possibility of electrical wire and water lines. Use a scanner to find out for sure.

Power Drill

Available in different chuck capacities, such as 1/4", 3/8" or 1/2". For example, 1/4" means that is the largest diameter shank that will fit the chuck. The speed of the drill also increases with the size.

Motor load limit can be light-, medium- or heady-duty. The higher the amp rating, the more powerful the drill. Drills rated at 2 amps are generally considered light-duty drills, while 5-amp drills are considered heavy-duty.

Tighten the drill bit in place with a chuck. A keyed chuck uses a rotary key to tighten and loosen the chuck. A keyless chuck is operated by hand.

Another feature on some drills is variable speed. They allow the operator to control the drill’s revolutions per minute, usually by varying pressure on the trigger switch. Some models also allow the user to vary the torque. Higher torque is better for driving screws, and higher speed is better for drilling holes.

A good quality 1/4” drill can drill through concrete, metal, plastic and other materials. Better for high speed and not high torque. Better for sanding and buffing than 3/8” or 1/2” drill sizes.

A 3/8” drill has more speed, but less power than a 1/2” drill. They are usually built with a double-reduction gear system. Can perform most of the drilling jobs a 1/4” drill can, and can handle a larger range of drill bits.

A 1/2” drill has high torque and slow speed, which is ideal for making large holes in metal and wood. Best drill for use wtih hole saws.

Cordless Drill

Operates with a rechargeable battery, with sizes ranging from 9.6 volts to 24 volts.

Most portable drill and popular among consumers and pro customers.

Lower-voltage drills cannot handle more heavy-duty drilling jobs.

An important feature is an adjustable clutch. This lets the user select the degree of force applied to the drill. This helps prevent the motor from stalling and overheating, which can damage the battery.

Hammer Drill

Used to drill quickly through concrete, stone, block and brick.

While the drill turns, the drill vibrates the chuck back and forth or side-to-side to help the bit chip the material while it is drilling.

Many models have a mode selector, allowing the operator to choose rotation only, like a conventional drill, and hammer drill, which combines the drill and hammer action. Better models might offer a hammer only option for chisel and scraper attachments.

Do not confuse with a rotary hammer, which can accommodate core bits up to 6” in diameter. These tools have unique bit drive and retention methods rather than the conventional geared chuck.

Manufacturers will measure speed by rpm (revolutions per minute), and the hammer action by bpm (blows per minute)

Angle Drill

Has an angled head designed for tight fits and close-quarter drilling.

Available in 3/8” or 1/2” sizes.

Some models feature an angle attachment that rotates the drill into any position, while a side handle allows one-hand operation and easy control.

Power Screwdriver

A common type is a variable-speed, reversible drywall screwdriver. It is designed for driving drywall, decking and other self-drilling screws. They offer higher speeds than a power drill.

A cordless, in-line screwdriver is handy for light-duty household applications. They have less power and speed than a power drill, but are easier to handle.