Bluing is a process usually used by gun owners and firearms manufacturers to improve the aesthetic value of their weapons. It provides the steel surface with a layer of protection against rust and corrosion while reducing potential glare as well. For most of the time, guns that utilize carbon steel components are the prime candidates for bluing but it’s totally possible to blue stainless steel as well. However, there are certain characteristics differences between the materials so knowing clearly how to blue stainless steel is really important. In the case that you are new to the subject and in need of detailed instruction, you come to the right place.
First, let us go through a couple of bluing concepts which you have to know in order to achieve the desired result. Technically speaking, bluing is more or less a conversion of red iron oxide (Fe2O3) to black iron oxide (Fe3O4). The name of the process actually comes from the blue-black appearance of the black iron oxide. There are many methods and solutions you can use to blue the steel such as hot bluing, cold bluing, niter bluing and so on. However, due to the unique qualities of the stainless steel, you can’t simply blue the material as you like.
In fact, stainless steel only accepts hot bluing and a limited number of chemicals. Unless you have sufficient equipment and skill, it’s advised to let the professional perform the bluing for you. High temperatures and dangerous chemicals mean a moment of carelessness shall make you pay a heavy price. The use of stainless steel alloy varies a lot from one manufacturer to the other which mean the bluing effect is not always consistent. If you are absolutely confident that you want and able to do this then you can proceed with the operation.
Necessary gears and tools
Safety is number one priority so protect your body as thorough as possible. The ideal setup is a pair of long sleeve gloves along with splash goggles and a completed facemask. Depend on the manufacturers manual, you have to prepare roughly 6 to 8 tanks to perform the bluing effectively and efficiently. Thermometers and stirring tools are also needed plus something to heat up the tanks like gas burners. Iron wire, stainless dipper and part basket are required to handle the guns components and adjust the bluing solution.
For the chemical, the bluing solution should be either Oxynate No. 84 or Du-Lite 3-0. Besides that, you must have water displacing oil and cleaning solution (Dicro-Clean 909). Again, don’t mess around with these things, handle them with extreme attention. Accidental exposure to the chemicals could result in serious injuries, seek medical help right away in that case. When everything is in place, put on your protective gear and let’s get down to business.
- Step 1: Ready the bluing tank
Fill the tank with a suitable amount of water then add in the bluing salt at the correct ration. In the usual case, you can find the manufacturer recommended ratio in the product manual. After that, slowly and steadily sir the tank to dissolve the salt, be careful since considerable heat might be generated in the process. When you are done, attach the thermometer to the tank and fire up the burner. Depend on what solution you use, the tank temperature must be maintained somewhere between 240 and 310 degrees Fahrenheit.
It’s essential to keep stirring the tank to prevent the forming of hot and cold areas. Once the solution reaches its boiling point, turn down the burner to about one-third of the boiling temperature and maintain it there.
- Step 2: Process the components of the gun
Prepare the components metal surface before you attempt to blue them using a variety of tool. Excessive buffing on stainless steel could result in a grainy appearance so do it with care. Next, suspend the components in a cleaning solution tank to get rid of dirt, oil, grease, crud, etc. Keep them in that state while you heat but not boil up the tank, ideally at 180 degrees Fahrenheit but it also depends on the manual. Wait for 10 – 15 minutes then get the components out and rinse them in a cold water tank. Use a soft brush to gently remove all the residues of the cleaning solution on the components.
- Step 3: Suspend the components in the bluing solution tank
Put the components into the tank and wait for 5 – 15 minutes. Should the solution is till boiling vigorously then the bluing shall happen naturally without fail. However, in the case that the bluing effect is not up to taste, you can try giving the components an acid bath (Hydrochloric Acid for example). They should start gassing approximately 2 to 3 minutes after exposure. Then you can put the components back into the bluing tank and increase the temperature till they turn blue.
- Step 4: Rinse the components in a cold water tank then transfer them to a hot one.
Following the treatment in the bluing tank, relocate the components to a cold water tank( not the tank from Step 2). Let them cool down while you take a closer look at the bluing effect. Check through every nook and cranny of the components in order to detect potential flaws like discolorations and blemishes. If nothing worrisome appear then promptly transfer the components against, this time to a hot water tank. The idea is to remove all the traces of the bluing solution and other chemicals.
- Step 5: Submerge the components in a tank filled with water displacing oil
At this final step, we let the components cool down in water displacing oil and that should be the end of the operation. Get them out after a couple minute then wipe clean the excess oil and reassemble the gun. The blue layer is rather delicate so don’t treat them roughly. Wait for a day to let the bluing properly cure before you want to do anything else.
And that is most of what you should know about stainless steel bluing, pretty straightforward, right? The entire may seem to be a bit tricky at first but knowing how to blue stainless steel is really handy from time to time. With the help of the information above, you should have little problem bluing your firearms on your own.