The purpose of this procedure is to determine the presence of mechanical damage@ wearthrough@ and other gross defects in the contact finish. Most contact finishes are intended to be protective@ and the presence of gross defects in the finish indicates a serious reduction of such protection. In addition@ the protection afforded by well applied finishes may be diminished by improper handiing during and following plating@ or as a result of mechanical damage during assembly or while in service. Gross defect tests can serve to indicate the existence of such damage. As an adjunct to wear testing and durability studies@ the tests in this procedure are used to detect undercoat andor substrate metal exposure during wear testing or through normal wear@ such as during mating cycles of a contact@ Many gross defect tests can detect as-plated large pores. However@ these tests are not designed to be porosity tests since they will not detect a sizable portion of the smaller intrinsic pores that may be present in the finish. The following test procedures are described herein: Dimethylglyoxime @MG) spot (see 7.1) DMG vapor'(see 7.2) Alkaline polysulfide immersion (see 7.3)