Edge, Types of Flat Spring Wire

Types of edges: a No. 1 edge is a prepared edge of a specified contour that requires a very accurate width or high quality edge finish; a No. 4 Edge is an approximately round edge produced by cold work when the edge finish is unimportant; and a No. 6 Edge is an approxi­mately square edge produced by edge rolling. The No. 2 Edge designation is no longer used. Nos. 3 and 5 are produced by slitting and are particular to that industry.