Easily releasable blind rivets

A blind rivet comprising a tubular member insertable through aligned holes in workpieces to be rivetted together from an outer accessible side to an inner non-accessible side, an enlarged separate retainer on one end of said tubular member having a cross-section larger than said holes on the outer side of the workpieces, said one end to be installed at said outer side, an expanding pin extending coaxially through said tubular member, an enlarged head on the inner end of said pin having a cross-section larger in size than the bore through said tubular member, but smaller than the hole in the workpiece on the inner side, a tapered expanding surface on said enlarged head of said pin on the side of said head adjacent said inner side of said tubular member so that when said expanding pin is drawn through said tubular member a limited distance said inner end of the tubular member is expanded radially outwardly to a cross-sectional size larger than the hole in the workpiece on the inner side, said retainer being removable from said tubular member so that said rivet may be removed from the workpieces without damaging them.