View Full Version : Blackening stainless steel

10-12-2009, 08:50 AM
Does anyone know of a easy way at home, to blacken stainless steel, so that it will withstand temperatures of 1000 degrees. I have a suppressor for an AR-15 that is full auto rated and under rapid fire the temperature can reach 900 degrees. I would like to darken the outside of this, but haven't figured out a way to do this without bead blasting the metal.

Bob D.
11-05-2009, 06:42 PM

Looks like this stuff can handle 1200 degrees. I haven't tried it myself, but Brownell's sells some of their products and I've never been disappointed by anything I've bought from them.;)

07-12-2017, 10:58 PM
Anyone got a good DIY for this? I don't need heat resistance, but salt would be good. Want to blacken fishing clips so the damn bluefish don't hit them.

Bob Ford
07-12-2017, 11:19 PM

Have used their product on guns used on fishing boats and it held up well. You sand blast or grind off if you don't like it. I coated a test piece of steel then tried to drill it. Turned a new 1/8th bit red .


John 242
07-15-2017, 01:36 PM
Gellfex, why not try some black paint; Rustoleum, Krylon or something like that?

I assume that your fishing clips are stainless steel, brass or aluminum. If that's the case then they should be pretty resistant to corrosion. If you want a little more corrosion resistance, then the GunKote, Durakote or CeraKote might be what you're looking for. If you just want to darken them, would flat black paint work?

If your fishing clips are aluminum, there's also a product called Aluma black sold by Birchwood Casey and available sometimes at sporting goods stores along with Brownells, Midway or Amazon. It will blacken aluminum parts, they don't always look great, but it will make them dark(er). They wouldn't be anymore corrosion resistant then they already are. Birchwood Casey also makes a product called Brass Black. I haven't used it, but it seems to work like Aluma Black. This might do the trick if your fishing clips are brass.

KG Gunkote (along with Durakote or Cerakote) is more durable than paint from a rattle can, but the application is a little more complicated and costs more. The cost and time is often worth it for paint gun parts, tools or whatever, but may not be worth it for fishing clips. However, done correctly, KG Gunkote on your fishing clips would likely last longer than spray paint and is more rust resistant. You can also buy Durakote in a spray can nowadays, and Brownells sells Aluma-hyde II in rattle cans. Something to think about.

This is an old thread, but at the beginning the OP asked about darkening stainless at home. I have used Brownells stainless bluing salts (Oxynate 84) quite a bit and have had mixed success. For small parts you could easily set up to use stainless salts at home, but it's probably not very economical. Oxy 84 will only blacken certain stainlesses, such as 416R, but will not work on most 300 series materials like 304. For 416 you sometimes have to "pickle" the parts in muriatic acid, which is a stinky and slightly dangerous process. To summarize, Oxy 84 works sometimes but is probably not what you want to be screwing with in a home shop situation.
What I recommend for unknown stainless steel gun parts is what Bob Ford recommends: KG Gunkote (or any other "gun paint").

I hope this helps or at least is food for thought. Good luck with those fishing clips. Bluefish any good eating? I was a west coast kid so our damn fish where bonito and mackerel. Bonito are great smoked.

08-19-2017, 11:18 AM
I recently had to soak something in muriatic acid, and I had left a stainless pick hook sitting in the solution. It was in there for about an hour. It turned black. Don't know the chemistry of that, but it might be an option.

08-20-2017, 09:02 AM
Some years ago I used a stainless steel beaker to hold some ferric chloride for copper etching... bad idea. I seem top recall that the inside of the beaker was a dark color after I transferred it to a glass container. Might be worth a try if you have a little ferric chloride around. YMMVG

for a little more about etching stainless steel

03-10-2018, 08:19 PM
Chlorides will crack stainless steel.