Workpiece-shaping tool assembly

A workpiece-shaping tool assembly, the assembly comprising:

• a drive shaft having an outer end centered on and rotatable about an axis;
• a tool body fittable with the end of the drive shaft;
• a ring shrink-fitted in the end of the tool body;
• a torque coupling formed by shaft splines formed axially inward of the ring on the drive shaft and tool splines formed on the tool body, complementary to the shaft splines, and interfitting radially with the shaft splines;
• a radial-force coupling formed by
• axially spaced inner and outer cylindrical shaft surfaces on the drive shaft, axially flanking the torque coupling, and centered on the axis and
• complementary respective axially spaced inner and outer cylindrical tool surfaces respectively formed on the tool body and ring, axially flanking the torque coupling, centered on the axis, and radially juxtaposed and bearing radially directly on the respective inner and outer shaft surfaces;
• and
• a tension rod having an inner end threadedly received in the shaft axially inward of the inner and outer shaft and tool surfaces and an outer end bearing axially on an annular end face of the ring and through the ring on the tool body.