Drill bits

Types

As an electrician, at various times you will have to drill holes in a range of different materials including timber, bricks, concrete, steel, etc. There is a range of different drill bits for specific materials or to suit particular drills. These drill bits would include:

• twist drill
• masonry drill
• spade bit
• auger bit.

Twist drills

Twist drills are used for drilling holes in a wide range of materials including timber, plastic, sheet metal and steel. Not suitable for masonry. Sizes vary from less than 1mm (drilling printed circuit boards) up to 25mm in diameter. The length of the drill is generally not very long, up to 12 times the diameter of the drill, so the depth of hole to be drilled can be limited. There are extra long versions available.

 

Masonry drills

As the name suggests these drills are for masonry (brick, stone, concrete, etc). They consist of a twist type drill with hardened tip (tungsten carbide) and need to be used with a hammer drill.

 

Spade bits

These bits are specifically for boring holes in timber. Sizes range from 6mm to 37mm and can have extra long shafts for drilling deep holes. These are useful for boring holes in timber frames to accommodate cable runs.

 

Auger

Augers are available for use with a power drill as well as hand operated versions. They can have extra long shafts, making them suitable for boring holes down through timber frames for cable runs.