Conventional point(118 degree) twist dril bits
Performance benefit:
1: General purpos
2: Widely available
3: Acceptable drill lift
4: Best suited in mild steel and aluminium
Comments
1: Not self-centering "walking" can occur on hard surface
2: May produce burrs on breakthrough
Split-point (118 degree and 135 degree) twist drill bits
Performance benefit:
1: Selft centering when drill with the drill bits
2: Excellent for portable drilling
3: Longer drill life for the drill bits
4: Good for drilling on curved surfaces
5: Improved penetration rates
6: Requires less effort
7: Breaks up chips
8: Best suited in alloy steels
Comments
1: Difficult regrind