Abstract: An oxide superconductor wire is prepared by preparing a length of precursor wire for processing into an oxide superconductor wire and coating the precursor wire with an isolating layer. The coated wire is wound onto a reel in a spiraling manner, such that each turn of the spiral is in substantial alignment with the preceding turn of the spiral along an axis perpendicular to the axis of winding. The wound precursor wire is then heated to form the oxide superconductor. The removable isolating layer is prepared by coating the wire with a solution including a metal compound and a porosity-inducing component, and heating the coated wire so as to induce porosity and control grain size of the metal compound so as to render the coating removable. The coating functions to isolate the overlapping turns of the wound wire from neighboring wires, so that no diffusion bonding or adherence between the turns occurs. The coating preferably comprises a material that can be reduced or decomposed to form a solderable metal.