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The authoritative public forumfor Metal Finishing 1989-2025
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Category: "Black Oxide, Bluing, Coloring, Patinas, Nitriding"
617/73. Black spots on chemically blackened brass - November 15
117/76. Standards for Oiling of Black Oxided Parts - October 15
362/14. 
Formula for cold blackening / cold black oxide
- October 6
11/50. 
How to Get Clear Coat Look from Gun Bluing?
- August 3
20713. How can nylok nuts be black oxided? - June 5
59418. Passivation after black oxide? - March 29
54394. Black Oxide on stainless steel: problems - March 21
61635. 
Hot Black Oxide Issue- brownish-green parts and black spots/streaks
- February 12
• Smut on the black oxide coatings - December 7
• Blackening gold with iodine - June 17
• Possible to black oxide Inconel? - May 14
• Blackening formulas for steel and cast iron - April 29
• Black Oxide poor coverage on welded part
• How often must cold black oxide bath be replaced?
• Does black oxide on stainless fasteners improve resistance to galling?
• How to do smut-free mid temp black oxide on wood screws - December 25
• Black Ox problems due to lot variations in type 300 SS? - December 20
• Black Oxide Coating Thickness - November 18
• Which oil BLACK OXIDE finish?
• Black oxide is salmon colored. Is copper the problem? - September 19
• Cold blackening on SS turns blue over time
• Mid temperature blackening smut issue
Rust on black oxide parts• Black oxide problems on 4340 steel