A CNC vertical milling machine has to cut a straight slot of 10 mm width and 2 mm depth by a cutter of 10 mm diameter between points (0,0) and (100,100) on the XY plane (dimensions in mm). The feed rate used for milling is 50 mm/min, milling time for the slot (in seconds) is
Answer: B
Given data, width (b) = 10 mm, depth = 2mm
Distance travelled for cut between points (0, 0) and (100,100)
By Pythagoras theorem
d = √(100⊃2;+ 100⊃2;) = 141.42mm
Feed rate f = 50 mm/min = 50/ 60 = 0.833 mm/ sec.
Time required to cut the distance (d)
t = d/f = 141.42/ 0.833 = 169.7 ≈ 170 sec.