Post by GZ22 (Copied from Modelgun Cleaning Guides)

In order to blue or blacken any metal properly, you need to follow some instructions:

1) Thoroughly degrease the metal using Birchwood Casey Cleaner/Degreaser or Isopropyl Alcohol on a firm sponge pad.

2) Apply Birchwood Casey Blue & Rust Remover with a saturated swab and allow to work for two minutes. Thoroughly scrub the surface with a piece of coarse steel wool dampened with Blue & Rust Remover, until the metal is gleaming.

3) Rinse the surface under running water, and then degrease and rinse and dry.

4) Polish the surface using varying grades of steel wool until you reach the desired finish. A bright, shiny surface equals a rich, reflective deep blue. A matt surface equals a finish akin to parkerizing.

5) Apply the bluing solution using a saturated swab, doing it in long strokes in one direction. Let it sit for the specified time stated on the solution bottle. Less time is better than more - don't leave it on too long.

6) Rinse the surface under cold running water to neutralize the reaction, and then dry. If there are any patches or uneven blotches, lightly blend the finish using 0000 steel wool during or after rinsing. Repeat steps 5 & 6 until the desired level of darkness is reached.

7) Once the final depth of colour is attained and you have blended the surface evenly, rinsed and dried it, saturate the surface with a good gun oil, and leave to cure for 24 hours. Wipe off excess oil and admire your handywork!

***Please Note***

The solutions used in this process are flammable, toxic and poisonous, so the use of good ventilation, eye/face protection, and gloves is strongly recommended. Always follow that safet precautions provided on the pack of each solution.

Here are some pictures of a real steel Remington 870 going through the process.



Before


















During












After

...Also forgot to add that once you have degreased, rinsed and dried it for the final time before bluing, DO NOT touch the surface with your bare hands, as even the slightest amount of oil or sweat will casue that spot to accept the bluing solution badly. Wear a pair of clean nitrile or rubber gloves. (Not the pair that you used whilst stripping and polishing).

Post by GZ22

... As for the Birchwood Casey solutions they have the following:

Perma Blue: Works on Steel only

Super Blue: Works on Steel only, provides the 'blackest' of the blues

Aluminum Black: Works on Aluminium and Zinc.

**NOTE**

If you use the Blue & Rust Remover on Zinc, it will phosphate the metal, creating a dense, porous grey coating. This is due to the amount of Phosphoric Acid in the solution. You will need to *thoroughly* abrade the surface with steel wool (start with Coarse and then move to Medium or Fine (00) in order to get it back to gleaming metal. I have used this on a Umarex B/F and it came up a treat, as per below: