A system comprising: a current control brush assembly, comprising: an axial button comprising a first electrically conductive housing retaining a first plurality of electrically conductive filaments, wherein the first plurality of electrically conductive filaments extends generally inward along an axial direction; and a radial shaft grounding ring coupled to the axial button, wherein the radial SGR comprises a second electrically conductive housing retaining a second plurality of electrically conductive filaments, wherein the second plurality of electrically conductive filaments is arranged circumferentially around the second electrically conductive housing, and the second plurality of electrically conductive filaments extends generally inward along a radial direction, characterized in that an outer diameter of the first electrically conductive housing is substantially equal to an inner diameter of the second electrically conductive housing, and the first electrically conductive housing is press fit into the second electrically conductive housing to couple the radial SGR to the axial button. a current control brush assembly, comprising: an axial button comprising a first electrically conductive housing retaining a first plurality of electrically conductive filaments, wherein the first plurality of electrically conductive filaments extends generally inward along an axial direction; and a radial shaft grounding ring coupled to the axial button, wherein the radial SGR comprises a second electrically conductive housing retaining a second plurality of electrically conductive filaments, wherein the second plurality of electrically conductive filaments is arranged circumferentially around the second electrically conductive housing, and the second plurality of electrically conductive filaments extends generally inward along a radial direction, characterized in that an outer diameter of the first electrically conductive housing is substantially equal to an inner diameter of the second electrically conductive housing, and the first electrically conductive housing is press fit into the second electrically conductive housing to couple the radial SGR to the axial button. an axial button comprising a first electrically conductive housing retaining a first plurality of electrically conductive filaments, wherein the first plurality of electrically conductive filaments extends generally inward along an axial direction; and a radial shaft grounding ring coupled to the axial button, wherein the radial SGR comprises a second electrically conductive housing retaining a second plurality of electrically conductive filaments, wherein the second plurality of electrically conductive filaments is arranged circumferentially around the second electrically conductive housing, and the second plurality of electrically conductive filaments extends generally inward along a radial direction, an outer diameter of the first electrically conductive housing is substantially equal to an inner diameter of the second electrically conductive housing, and the first electrically conductive housing is press fit into the second electrically conductive housing to couple the radial SGR to the axial button.