Providing printed circuitry in a sandwiched relation with a pair of flexible layers of non-conductive material, depositing solder pads on the printed circuitry and storing the resulting substrate on a drum, withdrawing the substrate from the drum and incrementally advancing it along a linear path, serially transporting solderless solar cells into engagement with the pads and thereafter heating the pads for thus attaching the cells to the circuitry, cleaning excess flux from the solar cells, encapsulating the cells in a protective coating and thereafter spirally winding the resulting array on a drum.