Abstract: The method of making a grid of a predetermined length embodying crossing longitudinally and transversely extending spaced parallel wires welded at their crossings wherein the portions of the longitudinally extending wires between the transversely extending wires contain depressions for receiving attaching elements at the ends of coiled springs, comprising forming the grid with the transverse wires spaced in the longitudinal direction of the grid so that any whole number of spaces in the longitudinal direction exceed the length of the assembly and then forming the depression in the portion of the longitudinally extending wires between the transversely extending wires by an amount such that collectively they reduce the distance between the transversely extending wires so that a whole number of the spaces between the transversely extending wires correspond to the length of the assembly desired.