An irradiation apparatus with a limited swivel rotator includes a drive ring and at least one mount affixed thereto. The drive ring has a defined drive axis of rotation being configured to rotate about a source container, like an X-ray tube. The mounts are affixed to the drive ring. Each of the mounts is configured to mount a material holder to the drive ring for rotating the material holder about the source container. The limited swivel rotator is in communication with each of the mounts and is configured to maintain a radial planetary position of the mounts and the material holders mounted thereto to maintain an initial horizontal orientation of the mounts and the material holders mounted thereto on the drive ring as the mounts and the material holders mounted thereto are moved around the source container by the drive ring.