The Double Dimple Magnetic Recording Head Suspension and Its Effect on Fly Height Variability

A gimbal forming modificaton is presented which, when implemented, leads to significant reduction in air bearing surface (ABS) static attitude and flying height variability within head-gimbal assembly (HGA) populations. The modification requires no additional parts or steps in the manufacture of the suspension assembly. An experimental test of the concept is described, along with the procedure on which it is based. The resulting reduction in product variability is obtained without measurement of (or tailoring to) the initial conditions of the constitutive parts of each HGA. A ≈ 50 percent reduction in static attitude variability, and a ≈ 33 percent reduction in flying variability, was experimentally shown to result from the adoption of the Double Dimple design concept, in all flying degrees of freedom.