Cold bluing a firearm

[Chrisoro]

My Marlin 1894C has some small areas where the bluing is worn, and I'm thinking of using a bottle of Skinner Blue which I bought once to fix it, but the instructions are a bit scarce. Yes, I am aware that cold bluing is primarily a cosmetic procedure, and don't result in the same rust resistance as warm bluing.

So, have anyone here done any kind of cold bluing, and have tips for how to get the best result, including what kind of oil to use? The instructions only state that one should ensure that the area is covered in oil afterwards, and don't tell how to accomplish this or what kind of oil one should use. (Engine oil? Olive oil? Baby oil? Oil of Olay?).

Thanks!

 

[lklawson]

My Marlin 1894C has some small areas where the bluing is worn, and I'm thinking of using a bottle of Skinner Blue which I bought once to fix it, but the instructions are a bit scarce. Yes, I am aware that cold bluing is primarily a cosmetic procedure, and don't result in the same rust resistance as warm bluing.

Don't bother with Hot Caustic Bluing. It's dangerous and the only advantage is that it's "fast" which means you can do a lot of pieces in comparatively large batches. If you're only bluing one or two firearms, do a Rust Blue using an "express" solution. It's easy to do, hard to screw up, historically accurate, inexpensive, safe, is "real" bluing, and yields beautiful results:

Kel Tec P11 refinish: If I can Rust Blue, you can too!

So, have anyone here done any kind of cold bluing,

Yes. You often have to shop around and try different cold blue solutions to find one which blends in well with your particular firearm. Most of them turn out blotchy anyway. All of them wear very quickly. They're basically a very thin copper or selenium paint. Essentially, I think cold bluing sucks.

and have tips for how to get the best result

Follow the manufacturer's instructions to the letter for best results. They usually say that you'll have to repeat their process several times, often it's recommended to pre-heat your metal with a heat gun or propane torch, and almost all of them require you to degrease first. If you don't degrease first, the application won't "stick" to the metal. The best way I've found to degrease is a 3 step process. Take your disassembled parts and wash in steaming hot water with "grease cutting" diswashing liquid (such as Dawn) and air dry in an oven on low or with a craft heat-gun. When dry, wash the parts again in 90% rubbing alcohol and air dry. Finally, clean the parts using non-Chlorinated Brake Cleaner. Be sure to wear rubber gloves so that you don't contaminate your parts with skin oils.

including what kind of oil to use? The instructions only state that one should ensure that the area is covered in oil afterwards, and don't tell how to accomplish this or what kind of oil one should use. (Engine oil? Olive oil? Baby oil? Oil of Olay?).

Thanks!

Any kind. Clean Motor Oil works. ATF works. Sewing Machine oil works. Knife honing oil works. Mineral Oil or Choji works. Cooking oils such as Olive oil can work fine too but they can oxidize and turn to sticky, gummy, booger-like films. Some veggie oils are more vulnerable to this than others, such as Corn Oil. If you chose a veggie oil, chose one with more anti-oxidant properties and a high Smoke Point. From memory, "Light" Olive oil has a high smoke point, higher than Canola, but there are others with higher still.

Peace favor your sword,
Kirk

 

[lklawson]

Any kind. Clean Motor Oil works. ATF works. Sewing Machine oil works. Knife honing oil works. Mineral Oil or Choji works. Cooking oils such as Olive oil can work fine too but they can oxidize and turn to sticky, gummy, booger-like films. Some veggie oils are more vulnerable to this than others, such as Corn Oil. If you chose a veggie oil, chose one with more anti-oxidant properties and a high Smoke Point. From memory, "Light" Olive oil has a high smoke point, higher than Canola, but there are others with higher still.

P.S.,

Of course, any "gun oil" works great too. RemOil, Outers, Breakfree CLP, Froglube, Hoppes Oil, etc.

Peace favor your sword,
Kirk