The authoritative public forum
  for Metal Finishing since 1989
-----

Black Oxide Handrail

2006

I am designing a steel stair and railing. I am very fond of the "Black Oxide" finish. Which seems to be commonly known as gun metal finish? I clearly only have a very basic understanding of the processes involved. I have had some material science courses in college, so I can grasp some of the technical issues. I have a few concerns about the "black oxide" process in regards to my design. The parts are to be welded together. It seems to me that the oxidation would decrease the weld strength. Is it advisable to weld "Black Oxidized" parts? Should I consider mechanical fastening or oxidizing after welding?

My other concern is the durability of the finish on a handrail, apparently it is suspect. It seems that I will need to "clear coat", which from what I have gathered from the finishing.com website can be as simple as a polyurethane. Are there special concerns when "clear coating" Cold Black Oxide, since it can rub off easily? Or is their a smarter solution to the design problem? Any help you can offer will be greatly appreciated.

Thank you,

Jesse HR Young
- Des Moines, Iowa

---

2006

Black oxide is very thin, and will wear through easily. It also offers little corrosion resistance unless topcoated with oil, wax, or, in your case, a clear finish. The automotive polyurethane clear coats are very durable and should do what you want. No problem to black oxide weldments.

However, once clearcoated, It may look just like gloss black paint.

Jeffrey Holmes, CEF
Spartanburg, South Carolina