Rake Angle: It is also known as helix angle. The angle between a plane passing through drill axis and leading edge of the land is known as rake or helix angle. It varies from 0° to 48°. Higher values are suitable for softer materials and lower values are suitable for harder materials.
Point Angle: It is also known as cutting edge angle. It is the angle included between the two opposite lips of a drill, measured in a plane containing the axis of the drill and both the lips. The most common value of the angle is 118°. Smaller point angle is suitable for brittle material and larger one for harder and tougher materials.
Chisel Edge Angle: The obtuse angle formed between the lip and the chisel edge is known as chisel edge angle. The greater the angle larger will be clearance. It ranges from 120° to 135°.
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