The Different Kinds of Drill Bits

Twist

• Twist drill bits are typically used to bore holes on metal sheets or panels, wood, and hard plastic. These drill bits come in various diameters, ranging from 0.8 to 12 mm, and consist of a spiral groove design at the tip. This is a common drill bit type used in most hand-held power drills and small machine drills. Twist drill bits are primarily used to drill screw holes, mounting holes, and to remove dust and debris from a slightly larger hole made using a different drill bit.

Screwdriver

• Screwdriver bits sport a hexagonal tip and are normally fitted onto rechargeable screwdrivers. They are not meant for high speed and hard material drilling due to the lack of rotating power of a rechargeable screwdriver. In most cases, screwdriver bits are primarily used to bore small pilot holes onto a material as a guide for a deeper and more powerful drill.

Masonry

• Masonry bits, as the name implies, are essentially used for stone, brick and concrete drilling. These drill bits are normally made out of high-quality tungsten carbide or a bronze alloy coated with silicone to withstand heat and friction. Some masonry bits can be fitted on a regular hand-held power drill. However, most are fitted on hammer action electric drills. Masonry bits come in different diameters, ranging from 4 to 16 mm.

  Since these drill bits take a lot of abuse, it is recommended either to use a reduced rotational speed or dip the tip into water every so often when drilling into a tough surface. This is to avoid overheating and to prevent the shattering of the drill bit.

Spur

• Commonly used for wood, glass, and ceramic surfaces, spur drill bits sport a spur designed configuration, somewhat similar to twist drill bits. This type of drill bit is often used for power drills and is great for boring a clean hole due to its longer and cleaner drill point.

Hole Saw

• Anyone needing to drill a larger hole onto a metal sheet or wooden surface will find the hole saw an invaluable type of drill bit. Basically, the hole saw is used to bore an 18 to 32 mm hole onto a surface straight through. This is possible through its design, consisting of a spiral groove followed by a large-diameter circular saw. Looking closely, this drill bit resembles a circular cookie cutter.