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Odd question about bluing steel/stainless steel

I have a simple question with what you may consider odd circumstances behind it. Let me explain:

I belong to a worldwide medieval reenactment group known as the Society for Creative Anachronism. As part of my activities with this hobby, I put on 60+ pounds of metal armor and bash my friends around with heavy wooden weapons. Fun stuff. I am currently re-doing my armor, and certain parts of it, most notably the knees, elbows, and gauntlets, are going to be exposed metal (the rest is covered by dyed leather, so isn't a problem).

I want these pieces to be a dark blue or black color, and to that end I am going to pick up a "home-blueing" kit, the kind used for gun barrels and muzzleloaders and the like. I would powder-coat them, but that tends to be a VERY expensive process, especially for such small pieces (it cost me $40+ to powdercoat my helmet glossy black, and although I was, and still am VERY happy with the results, I simply can't afford it for these pieces).

Now to the question: I have a choice of two materials for these pieces...16-gauge cold-rolled steel, or 16-gauge stainless steel. I would prefer to use the stainless for it's increased durability (in my experience fighting for 10 years, 16-gauge stainless is the same protection as 14-gauge cold-rolled, with less weight), but I have NO IDEA how well the stainless will take the bluing.

The last thing I blued was a muzzleloader barrel in high school (12+ years ago), and it obviously wasn't stainless. I know I can get good results with the cold-rolled being blued, but what results can I expect with stainless? Is there a specific type or brand of bluing that I can use to get good results? Or is stainless pretty much resistant to this process, at least what I can do at home?

Any help would be appreciated, as well as suggestions for alternative ways to get a black or dark blue glossy finish on stainless steel. Painting is not an attractive option, as it has to be touched-up far too often.

Thanks in advance!

Greg Swensrud
- San Diego, California

My recommendation would be to use the cold rolled, and have it black oxided (blued) by a finishing shop that does hot black oxide. This will be the most durable coating because the coloring actually becomes part of the steel. Bluing with a home kit is a depository coating that can be worn off pretty easily (then again, maybe you're such a good basher that you won't get hit much). Most finishing shops charge per pound if the job is big enough. Otherwise there is usually a minimum lot charge that should cover your pieces that shouldn't be too extravagant. Your hobby sounds interesting. Hope this helps.

Dan Brewer
chemical process supplier - Gurnee, Illinois

Thanks for the suggestion on the black oxide treatment. I'll look into it. I guess I have to assume by the total lack of other responses that most people agree with you about the matter. Fair enough, I'll go with mild steel and either a black oxide bath (if I can afford it) or the ol' home blueing kit.

Greg Swensrud
- San Diego, California

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...And if that fails, I've managed do achieve a good "black iron" look on my plastic modeling kits by covering a coat of matte black paint with graphite from a graphite pencil. Not good for big surfaces or metal bashing, I guess, but maybe for armor ornaments and parts that don't usually get hit.

Edgar Rolando Antunes livramento Castelo
- Lisbon, Portugal

Don't black ox stainless steel. I'm a machinist and know a thing or two about metal. the chromium in the stainless steel will prevent it the black ox from taking and could weaken it depending on what else it's alloyed with. The chemicals in the precursing acid dip and black oxide dip will destroy any nonferrous metals.

Robert Kollman
- marble North Carolina
October 2, 2009