A fiber filling apparatus comprising: a support; a movable fiber filling box adapted and arranged to be selectively lowered toward and lifted upwardly away from said support, wherein said fiber filling box has an open top, an open bottom, perimeter walls bounding a perimeter thereof, and at least one vertically slotted divider wall that divides, into at least two compartments, an interior space of said fiber filling box bounded within said perimeter walls, wherein said divider wall has vertically extending slot openings and vertically extending divider elements that alternate with one another horizontally along said divider wall, and wherein said slot openings are open to said open bottom of said fiber filling box; a fiber supply movably arranged above said fiber filling box and adapted to supply a loose fiber material into said compartments of said fiber filling box; wherein said at least one divider wall is configured and dimensioned to permit some cross-over of fibers of said loose fiber material between adjacent ones of said compartments through said vertically extending slot openings while sufficiently bounding said loose fiber material to maintain different thicknesses and/or densities of said loose fiber material respectively in said compartments; a fiber filling apparatus machine frame to which said support is vertically immovably connected, and a first lift arrangement connected to said machine frame and to said fiber filling box and adapted to lift and lower said fiber filling box relative to said support; a plurality of hold-down members adapted and arranged to be selectively lowered toward and lifted away from said fiber material in said compartments of said fiber filling box whereby said hold-down members are adapted to compress said fiber material and hold down said fiber material before, while and after said fiber filling box is lifted away from said support and said fiber material; and a second lift arrangement connected to said machine frame and to said hold-down members and adapted to lift and lower said hold-down members relative to said support. a support; a movable fiber filling box adapted and arranged to be selectively lowered toward and lifted upwardly away from said support, wherein said fiber filling box has an open top, an open bottom, perimeter walls bounding a perimeter thereof, and at least one vertically slotted divider wall that divides, into at least two compartments, an interior space of said fiber filling box bounded within said perimeter walls, wherein said divider wall has vertically extending slot openings and vertically extending divider elements that alternate with one another horizontally along said divider wall, and wherein said slot openings are open to said open bottom of said fiber filling box; a fiber supply movably arranged above said fiber filling box and adapted to supply a loose fiber material into said compartments of said fiber filling box; wherein said at least one divider wall is configured and dimensioned to permit some cross-over of fibers of said loose fiber material between adjacent ones of said compartments through said vertically extending slot openings while sufficiently bounding said loose fiber material to maintain different thicknesses and/or densities of said loose fiber material respectively in said compartments; a fiber filling apparatus machine frame to which said support is vertically immovably connected, and a first lift arrangement connected to said machine frame and to said fiber filling box and adapted to lift and lower said fiber filling box relative to said support; a plurality of hold-down members adapted and arranged to be selectively lowered toward and lifted away from said fiber material in said compartments of said fiber filling box whereby said hold-down members are adapted to compress said fiber material and hold down said fiber material before, while and after said fiber filling box is lifted away from said support and said fiber material; and a second lift arrangement connected to said machine frame and to said hold-down members and adapted to lift and lower said hold-down members relative to said support.