A multi-axis roll-forming system for forming a stepped diameter in a cylinder. The system includes a support configured to spin about a rotation axis while supporting a workpiece including a cylinder. A first actuator is configured to translate a first roller perpendicular to rotation axis. The first roller includes a truncated conical work surface configured to press against the inward-facing surface of the cylinder to angle it outward according to a slant angle of the truncated conical work surface.