The point angle is selected to suit the hardness and
brittleness of the material being drilled.
Harder materials have higher point angles, soft
materials have lower point angles.
An increase in the drill point angle leads to an
increase in the thrust force and a decrease in the torque due to increase of
the orthogonal rake angle.
This angle (half) refers to side cutting edge angle of a
single point tool.
Standard Point Angle is 118°
It is 116°
to 118° for medium hard
steel and cast iron
It is 125° for hardened steelIt is 130° to 140° for brass and bronze
It is only 60° for wood and plastics
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