Problem 7: Compute the maximum repeated torque that may be safely applied to the shaft if it is to be made from SAE 1141 OQT 1100 steel. Assume the torsional shear stress 7 must be less than the Sy torsional design stress Ta = 8 12 mm dia. r=2.0 mm r= 1.0 mm 24 mm dia. 16 mm dia.