Cutting data

vc (m/min)​	​
​	fn (mm/r)                  ​

​Effects of cutting speed – v_c (m/min(ft/min))

Cutting speed is the main factor, along with material hardness, that affects tool life and power consumption.

• The largest factor determining tool life
• ffects the power P_c (kW) and torque M_c (Nm)
• Higher speed generates higher temperature and increased flank wear, especially on the peripheral corner
• Higher speed is beneficial for chip formation in soft, long-chipping materials, i.e. low carbon steel
• Too high cutting speed:
• Rapid flank wear
• Plastic deformation
• Poor hole quality and bad hole tolerance
• Too low cutting speed:
• Built-up edge
• Bad chip evacuation
• Longer time in cut
  

Effects of feed – f_n (mm/r(in/r))

• Influences chip formation, surface finish and hole quality.
• Affects the power P_c (kW) and torque M_c (Nm)
• High feed affects the feed force F_f (N), to be considered when conditions are unstable
• Contributes to mechanical and thermal stress
• High feed rate:
• Harder chip breaking
• Less time in cut
• Less tool wear but increased risk for drill breakages
• Reduced hole quality
• Low feed rate:
• Longer, thinner chips
• Quality improvement
• Accelerated tool wear
• Longer time in cut