We developed a simple approach to design and fabricate precisely controlled coiled nanofibers via the micromanufacture of electrospun nanofibers. The fabrication set-up was specially designed so that one stream of polyvinyl pyrrolidone (PVP) sol with ferric nitrate was electrospun into a fiber bundle. This bundle acted as an axis that was collected between two opposite rotating needles while another stream of PVP sol, containing copper nitrate, was electrospun around the fiber bundle axis to form a coil. By altering the elements in the precursor solution, copper microsolenoids with magnetite (Fe3O4) cores were fabricated followed by annealing and deoxidation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4773365]