A system utilizing a rotary atomizer for applying a liquid based substance to particles. In one example, a motor provides an in-line, direct drive force on a cage atomizer. With some systems, the cage atomizer has a vertical axis of rotation. With some systems, the motor is mounted external to the particle path and supported by a housing structure that provides an angled particle path. With some systems, other types of rotary atomizers may be used such as disk, bowl, or hollow disk rotary atomizers. With some examples of cage atomizers, a first portion of the cage atomizer may include a thread set that screws to a thread set of a second portion to hold a perforated structure in place. With some systems, the thread sets surround the axis of rotation.