Sulfuric Acid Anodize Mil-A-8625F Ty2 TYPE 2 "Sulfuric Acid Anodize" Mil-A-8625 Ty 2 Sulfuric Acid Anodize Class1(NonDye),Class 2 (Dye) Seal Options: Hot DI Water, Nickel Acetate, Sodium Dichromate, Dilute Chromate, Duplex Seal, Teflon Impregnation. Hard Anodize Mil-A-8625F Ty3 TYPE 3 "Hard Anodize" Mil-A-8625 Ty3 Hard Acid Anodize Class1(NonDye),Class 2 (Dye) Seal Options: Hot DI Water, Nickel Acetate, Sodium Dichromate, Dilute Chromate, Duplex Seal, Teflon Impregnation. Successful use of anodic coatings, especially hard anodize, depends on proper product design. Because of the manner of formation, anodic coatings will develop voids at sharp corners and edges. Sharp edges and corners are difficult to anodize satisfactorily and in general should be avoided. All edges and inside corners should be radiused prior to anodizing. Chamfering should not be used unless resulting sharp edges are radiused. Nominal coating thickness: .002 inch (2.0 mils) +/-20%. Allowance must be made for dimensional increase. An increase in dimension, equal to 12 of the coating thickness, can be expected for each surface. In the case of small holes and tapped holes, coating thickness can vary from no film to full thickness. In general, holes over 14 inch should be anodized.Major and minor thread dimensions will be increased by 2 x's the build up thickness. Aluminum Bright Dip - bright dip is a chemical polishing pretreatment to create bright metal finishing on aluminum.