Casting Study: Tuner Housing

Two M4 threads were needed on this zinc die casting in Z410 alloy (equivalent to BS 1004B). Because the holes were at 90° and in different planes, the threading could not be carried out in a single operation. By comparison with two separate threading operations it proved more economical to provide location for two hexagonal nuts where the threads were required, and then to retain the nuts by crimping. Two lips were included on each location, angled in the direction of ejection from the die. After placing the nuts into their locations, all four lips are crimped over in a single operation so fixing the nuts firmly into place.