Patent ID: 7930954

Claim:
A forging die production method comprising: providing a ball end mill having a surface which has undergone a hardening treatment; providing a forging die material to be cut by the ball mill end; and cutting the forging die material by controlling the ball end mill so that a length of tool extension L (mm), radius R (mm) of a cutting edge of the ball end mill, spindle speed A (rpm) and feed rate B (mm/min) satisfy (B/A) 2 ×(L/(2×R))=0.01 to 0.05, and wherein the forging die production method includes at least rough cutting, heat treatment, finish cutting and profile cutting, the cutting step is for performing the profile cutting, the profile cutting includes at least three steps wherein pick feeds in respective steps are in proportions of (1.2 to 2):(0.2 to 0.5):(0.03 to 0.05), and a feed direction includes at least one of a direction in relation to contour line processing and a direction in relation to circulation milling.