By Keith Wood
Rust Bluing: Is it really the gun finish for the hobbyist?
- A heat source capable of boiling water
The first step was to degrease the steel and my wire brush—any traces of oil or grease will show up on the final finish. Remember that oil can seep out of receiver threads, crew holes, etc. Wearing gloves, I boiled the steel in detergent and then swabbed it in acetone. From this point forward, I did not touch the steel with my bare hands.
The solution is applied very sparingly (I used a cotton bore patch) in long, even strokes—don’t scrub! The metal is then allowed to rust for about three hours—this is going to depend on factors such as humidity.
In some climates, you may need to use a “sweat box” or hang the steel in a bathroom. My entire state is a sweat box so that was not necessary for me. A coat of red rust will form, and for once in your life this is a good thing. After three or so hours, re-coat the steel with solution.
It’s time to convert that rust before it pits the metal, so crank up your heat source (I used my barbecue grill—very sophisticated) and bring the water to a boil.
Use the steel wire to suspend the parts into the boiling water (do I need to tell you to be careful?).
This is where I ran into some trouble: Many sources (including the instructions on one of the solutions) tell you to use distilled water for the boiling. I bought several gallons of the Crystal brand of distilled water and boiled, and boiled and boiled. I could not get the red rust to turn black. I scrubbed my tank, I boiled for more time, I tried a different tank—nothing worked.
Finally, a gunsmith online suggested that I try a different water source. I used the water that is expelled from my home’s A/C unit and the rust turned black in seconds. Find a source of water that works for you but don’t be afraid to experiment with different sources to find the right one.