On this page we will show different tips, tricks and techniques for specific problems and to achieve different results.
Restoration (as mentioned before) is usually preferable to outright repair if the firearm has any collector value, or if you have a personal connection to it's history. So unless there is an absolute need for returning the condition to perfect, I always restore. When the metal has an aged grayer finish from wear, it can be hard to blend in the new bluing because it will get too dark. THe prime temperature for this bluing is between 90 and 150 degrees. But the opposite also holds true. To slow down the bluing process - get the metal cold. A refrigerator is about the right temperature to slow the bluing down. Example: A Civil War musket with an old gray finish with some rust on it. If I use the bluing with some #0000 steel wool to remove the rust, I would then get the metal cold, and blue it at about 40-50 degrees. This makes the bluing slow down and I can stop it (by wiping it off and applying oil) while it is still gray, which more accurately matches the rest of the gun.
ALLOY Receivers are more difficult to blue, seeing that they have less ferrous (steel) content. Here is another technique to enhance the darkening process. I call it a modified "cold-rust blue" technique. Following all the rules already mentioned to get it as dark as possible is where you start. However, we finish differently. Instead of oiling the metal right after bluing, wipe it dry, and then put the firearm in an area that is humid or damp. If you don't have a sweatbox, the laundry room is a great place to do this. Let the metal sit (unoiled) until a light rust forms. This rust layer should be so light that you can rub it off with your fingers. Each area is different, but once you have determined about how long that rusting process takes, you can usually count on it being nearly the same time for your next coat. Wipe the rust off with a cloth and blue the metal again. Wipe that dry, and Don't oil it. Let it rust again. Each time, the bluing gets to soak in farther and will deepen the color. When it looks right, oil it and go shooting!
Here is another thing to do using the method above. In the stage where you are allowing it to form a light rust; let it rust just a little more than the dusty stuff you can easily wipe off. Now just quench the metal with oil and you will have a blued gun with some of the brown patina that marks it as an older gun in great shape (and apparently un-"repaired").
Aluminum and Stainless steel will not blue because bluing is a "rusting" process and they can't rust. So what do you do with that aluminum receiver or trigger strap that is scratched or worn? I've tested virtually every "aluminum black" that is out there, and they don't work very well! What really works is "high-temperature engine paint". You can get it at NAPA, AutoZone, Champion, etc. This paint is designed to hold onto an aluminum engine block on a NASCAR racing engine at 2000 degrees! It holds up to high tech fuel spills and being sand-blasted at 200 mph as the car goes around the track ... it WILL hold up on your receiver! The trick is to apply it the way we've all been taught to paint (but few of us actually DO). Dust it on the degreased aluminum part as if you were air-brushing it. Put it on so thin (by spraying it from a distance) that it barely turns gray. Let it dry. Do it again. If it takes 3 or 4 coats to get it dark, you are doing it right. The thinner you can get it and still acheive a black finish - the better. If you want extra durability - after it is dry, bake it in an oven at the lowest temperature your oven goes to (about 150 degrees) for about 10 minutes. Then let it cool. It looks and wears as if you had it anodized! Because you are just "dusting" it on, your texture will remain unchanged. Parkerizing will look parkerized, and shiny will stay shiny.
You can dip pieces into this bluing, but make sure they are thoroughly degreased, and only give them about 30 seconds in the bluing and then check them. You can return the metal to the bluing to gain more darkness. I do all of mine in 30 second chunks. As the bluing loses strength, it will take longer to acheive a darker color. What you DON'T want to do is to immerse the metal and then leave it for too long. You are dealing with acids here ... too long in the tank, and you'll have pitting or surface damage. You went to all that trouble to make the texture perfect, don't lose it by etching the metal by leaving it in the liquid too long.
For soldered or brazed joints that won't blue because they aren't steel - spray with the engine paint and wipe with a cloth around your finger tip (like smoothing silicone sealer on tile joints) so that only the solder keeps any paint on it.
If the firearm has been through a fire, the metal has a thin coat of a greasy alkaline residue from the smoke. Because the metal was hot when the smoke damage occurred - there is an alkaline residue down into the pores of the metal. Now that the metal is at room temperature, those pores have closed up. Normal degreasing does not remove this deep seated film. So, Warm the metal with a hairdryer and while it is warm, wash it with a mild acid such as vinegar, or even muriatic acid (thinned way down with water). Rinse that off with water, wipe dry and apply the bluing as normal. This procedure neutralizes the alkali and allows the bluing (acid) to work.
As other questions arise, I'll be adding to this page. For direct help, e-mail me at firstname.lastname@example.org.