The Different Types of Drill Bits

Learn about the basic types of drill bits used for wood, metal and masonry.
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Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

©2007 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

©2007 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

©2007 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

©2007 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

Photo By: DK - Do It Yourself Home Improvement ©2009 Dorling Kindersley Limited

©2007 Dorling Kindersley Limited

Brad Point (Dowel) Bits for Wood

These are one of the three main types of wood drill bits, they are characterized by the small point at the tip of the bit. Spurs on either side of the point will cut clean, straight holes. They are suitable for all types of wood and come in a huge range of sizes and lengths.

Auger Drill Bits

These cut large, deep accurate holes. The spiraling shaft comes to a fine, threaded point. Carbon-steel bits are best and can be resharpened.

Wood Spade or Paddle Bits

The pointed tip begins the hole and the paddle-shaped blade bores large, wide holes. The size is clearly marked on the paddle's face.

Metal Drill Bits

These are known as high-speed steel (HSS) bits and are characterized by their black color. More expensive, durable ones may contain cobalt or be titanium-coated. They can also be used on wood or plastic, but they last longer if reserved for metalwork.

Masonry Drill Bits

These can cut into many masonry surfaces. The shaft spirals up to a tip that is often composed of an extra-hardened material. Bit colors vary because of the different materials used. The tip may be a different color from the shaft due to a hardened coating. For instance, a chrome-vanadium shaft may be finished with a tungsten-carbide tip.

Storing Drill Bits

Most types of drill bits are available in a wide range of sizes and qualities, and often come in sets, which can be economical if you do a lot of drilling. For the best results, always use the bit that is recommended for a specific job. Some sets contain many bits of the same type (those shown here are HSS bits); others contain the most common sizes of masonry, wood and HSS bits.

SDS Bits

In addition to the standard drill bits, there is a wide range of specialty bits are available made for a specific task, or to fit a particular type of chuck. These are made specifically to fit an SDS chuck mechanism, and won’t work with any other. The end that fits into the chuck has a fluted appearance; the drilling part of the shaft is normal.

Countersink Bits

As well as drilling a hole, these bits also cut a space for screw heads. They are ideal for preventing wood from splitting.

Specialty Woodworking Bits

Countersink bit (left) enlarges a hole's opening so that a screw can sit flush. A plug cutter (right) cuts wooden plugs that can be used to cover screw heads. It removes the plug through the side opening in the bit. A hinge cutter (middle) has a tungsten-carbide tip to cut holes for kitchen cabinet door hinges.

Tile and Glass Bits

The spear-shaped tungsten-carbide tip penetrates a tile or piece of glass, then enlarges the hole to the diameter of the tip's base.

Flexible Bit and Hole Cutter

A flexible drill shaft (left) attaches to the chuck and allows a drill to be used in an otherwise inaccessible area. The flexible shaft maneuvers bit into tight spaces. It cannot be used with the drill in reverse action. A hole cutter bit (right) sometimes called a hole-saw, comes in various sizes for cutting wood and metal. The drill bit cuts first, then the round cutter makes a larger hole.

Flat-Head Screwdriver Bits

Some bits insert directly into the chuck, but most need to be put in a bit holder, which is then inserted into the chuck. These are designed for use with slot-headed screws.

Phillips Screwdriver Bits

Screws with a Phillips head must be driven by a corresponding bit.

Posidriv Screwdriver Bits

Like Phillips bits, these are made to drive a particular type of screw.

Square Drive Bits

These bits are often used for driving deck screws.

Driver Bit Holders and Nut Driver

To work as a screwdriver, a drill-driver needs an attachment to hold bits in place. It is also possible to insert specialty bits into the chuck. The standard holder (bottom) holds the bit and in the chuck. The quick-release bit holder (middle) has a quick-release action mechanism that makes changing the bit very easy. The nut driver (top) is used for tightening nuts or bolts.