Captivating a fastener to a workpiece

A method of forming an assembly wherein a fastener is captivated within a workpiece, comprising the steps of:

• fabricating a workpiece from a deformable material having a predetermined degree of resiliency and a predetermined degree of elastic memory;
• defining an aperture within said workpiece such that said aperture has a predetermined diameter;
• fabricating a fastener, having a shank portion and wing means formed upon said shank portion of said fastener, from a relatively hard, non-deformable material as compared with said material of said workpiece, said wing means defining an outer diameter which is greater than said predetermined diameter of said aperture of said workpiece, and said wing means have a rounded cross-sectional configuration;
• inserting said shank portion of said fastener into said aperture of said workpiece until said wing means of said shank portion of said fastener engages a marginal portion of said workpiece which defines said aperture;
• and
• applying a force to said fastener so as to cause said wing means of said shank portion of said fastener to be forced through said aperture of said workpiece and thereby swage said marginal portion of said workpiece defining said aperture, thereby increasing said diameter of said aperture of said workpiece to a predetermined degree which is sufficient to permit passage of said wing means of said shank portion of said fastener therethrough while permitting said swaged marginal portion of said workpiece to return towards its original position and condition in accordance with said predetermined resiliency and elastic memory properties thereof so that said aperture of said workpiece substantially achieves its original diametrical dimension, which is smaller than said outer diameter of said wing means of said shank portion of said fastener, so as to retain said fastener at a pre-assembled position within said workpiece after passage of said wing means of said shank portion of said fastener through said aperture of said workpiece as a result of engagement of said wing means directly with said marginal portion of said workpiece defining said aperture within said workpiece.