Nanofibers are microstructured materials that span a broad range of applications from tissue
engineering scaffolds to polymer transistors. An efficient method of nanofiber production is rotary
jet-spinning (RJS), consisting of a perforated reservoir rotating at high speeds along its axis of
symmetry, which propels a liquid, polymeric jet out of the reservoir orifice that stretches, dries, and
eventually solidifies to form nanoscale fibers. We report a minimal scaling framework
complemented by a semi-analytic and numerical approach to characterize the regimes of nanofiber
production, leading to a theoretical model for the fiber radius consistent with experimental
observations. In addition to providing a mechanism for the formation of nanofibers, our study
yields a phase diagram for the design of continuous nanofibers as a function of process parameters
with implications for the morphological quality of fibers.