A magnetic screw device comprising a fastening stem, a housing, a magnet assembly, and one or more magnets, wherein the fastening stem comprises a first end, a second end, a shank therebetween, and a longitudinal axis therebetween, wherein the first end comprises a spherical or part spherical surface, the second end comprises a taper to a pointed or approximately pointed shape, and the shank comprises a thread; the housing comprises a top end, a bottom end, a wall therebetween, and a bore between the top end and bottom end that defines an inner surface, wherein a portion of the inner surface adjacent to the bottom end comprises a concave spherical or part-spherical surface that is configured to engage with the spherical or part-spherical surface of the first end of the fastening stem; and wherein the housing comprises a first slot and a second slot that extends from the top end towards the bottom end and is located on opposing sites of the wall; the magnet assembly comprises a shaft, a magnet holder on one or both ends of the shaft, a removable holder cap for each magnet holder, a longitudinal axis extending between the ends of the shaft, and a sleeve adjacent to each end of the shaft, wherein each magnet holder comprises an outer surface, a bore defining an inner surface, a closed end, and an open end; wherein each holder cap is configured to enclose the open end of the magnet holder; wherein the shaft is removably received by the first slot and second slot of the housing; and wherein the shaft is configured to extend between the first slot and the second slot of the housing; and each magnet is configured to be received by one of the magnet holders. the fastening stem comprises a first end, a second end, a shank therebetween, and a longitudinal axis therebetween, wherein the first end comprises a spherical or part spherical surface, the second end comprises a taper to a pointed or approximately pointed shape, and the shank comprises a thread; the housing comprises a top end, a bottom end, a wall therebetween, and a bore between the top end and bottom end that defines an inner surface, wherein a portion of the inner surface adjacent to the bottom end comprises a concave spherical or part-spherical surface that is configured to engage with the spherical or part-spherical surface of the first end of the fastening stem; and wherein the housing comprises a first slot and a second slot that extends from the top end towards the bottom end and is located on opposing sites of the wall; the magnet assembly comprises a shaft, a magnet holder on one or both ends of the shaft, a removable holder cap for each magnet holder, a longitudinal axis extending between the ends of the shaft, and a sleeve adjacent to each end of the shaft, wherein each magnet holder comprises an outer surface, a bore defining an inner surface, a closed end, and an open end; wherein each holder cap is configured to enclose the open end of the magnet holder; wherein the shaft is removably received by the first slot and second slot of the housing; and wherein the shaft is configured to extend between the first slot and the second slot of the housing; and each magnet is configured to be received by one of the magnet holders.