Question

25. Secondary shear in sheet metal cutting operations occurs due to
a. Too tight clearance
b. Optimum clearance
c. Too loose clearance
d. All of the above​

Answer 1

If not enough cutting clearance is provided, the fracture lines propagating from the punch and die will not line up. Noncontinuous fracture lines, in the sheet metal, usually result in secondary shearing and a deformed edge surface. The greater the sheet metal thickness, the higher the clearance value should be.