Metal coating application onto optical fibers by the freezing technique is accompanied by the emergence of cavities empty of metal, which are situated at regular intervals along the fiber. This article attempts to explain the nature of this phenomenon, which is shown to be inherent in the freezing technique. The regular cavities are due to the instability of the melt flow during the phase transition process at the point of contact of the cool fiber and the melt. Resonance of one of the eigen vibrations of the entrance meniscus with chaotic perturbations of the melt flow accounts for the periodicity of the cavities. The results of the theoretical analysis are confirmed by the experimental data. The conclusions of this analysis allow one to explain the presence of a similar phenomenon in the “spinning” process used for the fabrication of amorphous-alloy thin ribbons. ©1997 American Institute of Physics.