An auger bit is a tool that bores a hole. In the middle ages, carpenters used a hand held auger to drill holes in wood, allowing them to insert pegs into furniture. In modern times, auger bits can be used to drill through wood, metal, rock, concrete, soil or ice. Different bits are rated to drill through different surfaces and typically are marked as such.
The types of auger bits most people use around the house are also known as spade bits or paddle bits. These bits have a wide, flat cutting surface at the end and can be used in a hand-held power drill. These bits drill holes on average of 0.5 inches to 1 inch (1.2 cm to 2.54 cm), depending on the size of the bit. These types of bits are typically used to install or repair electric wiring or to make holes in doors to install door handles.
Auger bits are rated to drill through specific materials or surfaces. For example, bits that are rated as “nail biters” can be used to remove nails simply by creating a hole where the nail used to be. Paddle or spade bits can be used to drill through ice for ice fishing or for creative purposes, such as building bird houses. Bits that are rated for rock or concrete can dig holes through these surfaces. Rock or concrete bits are usually used with a hand-held, powered hammer drill; the hammer drill adds additional force by rotating and thrusting forward at the same time. These are often used to install post holes for new fences or for drilling through concrete without rebar to install t-posts.
Soil auger bits are often used for tilling hard, compacted soil or for creating holes in the ground for new plantings. They typically range in size from 6 to 12 inches (15 cm to 30 cm) in diameter and can be as long as 29 inches (73.6 cm). Some earth auger bits can be used with a hand-held power drill, but the larger and longer bits are usually designed to be used with a gas-powered auger machine.
Auger bits are also used in the mining and oil industries to dig into the earth’s surface in search of natural resources. These bits require large, specialized equipment to run, as they can be as large as buses and can drill as deep as 200 feet (60.96 m). Bits this large are designed not only to drill through the earth, but also to remove the materials to dump into large trucks or alternate locations.
The key to success with auger bits is to make sure the particular bit is designed to drill through the specific surface. Wood bits should be used for wood, concrete bits for concrete, and so forth. Although a high-powered drill is not necessary for most uses of auger bits, the more powerful the drill, the easier the job may be.