Rust Bluing

[RHarris]

Could someone describe the process of "rust bluing".

I've heard it mentioned here before and remember reading something about it at one time, but am having difficulties getting any information about it.

 

[dwesson445]

Grab a Brownell's catalog. They have so many different products you can read the descriptions and get a pretty good idea of what different processes do and how they work. I'm thinking of rust bluing a new Rolling Block I'm building. I have a friend at work who's done it before, so I'll use him to figure out which way is up.

 

[Dfariswheel]

In a nut shell:
The part is immersed in boiling water, when it is removed the heat causes the water to evaporate leaving dry, hot metal.
The bluing chemical is swabbed on the metal, and allowed to work for a period of time.
The "rust" that is formed, is "carded" off with steel wool, and the part is placed into hot water again.
The process is repeated, until the depth of finish is obtained.

There are a number of variations of this process. Although very slow, it is a process that can be done at home, and is the best "true blue" gun finish there is. This is the process some of the very high-end custom 'smith's use.