1. In a rod wrapping machine for winding elongated articles with a filament in different portions, the machine having a plurality of winding head frames mounted to be laterally movable, each frame containing a central opening and a radial opening leading to said central opening, a sector gear having an opening and being rotatably mounted in the central opening of each frame, elongated articles to be wound being laterally inserted through the radial openings in said frames and the openings in said sector gears to extend through the openings in said frames, two drive gears mounted on each frame meshing with a sector gear, said drive gears being spaced apart about each of said sector gears a distance greater than the openings in said sector gears, means driving said drive gears to rotate said sector gears, said means driving said drive gears also moving said frames laterally during winding, and filament dispensing means on each of said sector gears rotating about the elongated article to wind filaments about portions of the elongated article; the improvement comprising, in combination, said sector gears each having an outer rim containing an opening, gear teeth projecting from said outer rim, a central wall extending inward from opening in said outer rim forming the sides of a radial channel and curving to form a central space, and a web extending between said central wall and said rim forming an end of said sector gear, said central wall and said rim being substantially the same width.