The included angle of a drill bit is defined as the angle between which features?

The included angle of a drill bit is defined as the angle between which features?

• A. The two cutting edges
• B. The lip clearance and flute
• C. The tip and shank
• D. The body and shank

Answer: (B)

The included angle is the angle formed at the drill tip by the two cutting edges as they meet there. This angle defines how sharp or blunt the point is and directly influences how the drill bites into material and how chips are formed and evacuated. A common general-purpose value is about 118 degrees; a larger angle makes a flatter, stronger point that wears longer, while a smaller angle creates a sharper point that cuts more aggressively but can be less durable. This concept is separate from lip clearance or the flute: lip clearance relates to the clearance between the cutting edge and the surface to prevent rubbing, and the flute is the groove that carries chips away. It also isn’t about the tip’s relation to the shank or body.

The included angle is the angle formed at the drill tip by the two cutting edges as they meet there. This angle defines how sharp or blunt the point is and directly influences how the drill bites into material and how chips are formed and evacuated. A common general-purpose value is about 118 degrees; a larger angle makes a flatter, stronger point that wears longer, while a smaller angle creates a sharper point that cuts more aggressively but can be less durable. This concept is separate from lip clearance or the flute: lip clearance relates to the clearance between the cutting edge and the surface to prevent rubbing, and the flute is the groove that carries chips away. It also isn’t about the tip’s relation to the shank or body.