The bearing (10) is for automatic assembly by a machine with grab and angular centring tool (46). Faces (52,54) on the tool include the correct angle for centring the corner of the leaf. The two arms (20,22) of the angular component (10) are joined together preferably at right angles, each bearing against a mating face (52,54) on the tool. A bearing component (28) is bolted or welded (30) to the outside surface (36) of one of the arms (20). A face on this arm or the bearing mounting portion (32) bears against one (52) on the tool. The other arm (22) has a raised supporting portion (38) forming a face (58) bearing against the other face (54) on the tool.
