Rust Blue for Dummies (like me)

As much as I like Van’s Instant Blue it has it’s limitations, and depending on the steel results can be quite variable. It is and will remain my go-to cold blue, but I wanted something a little more professional. Rust blue seemed to be an option that fits my circumstances, and after researching the subject I decided to try Mark Lee Express Blue #1. This is a product that claims to produce a good finish in ‘as little as an hour.’ 

I bought the small bottle (4oz.) from Track of the Wolf.  Including shipping it ran about $17. Service was prompt and the package arrived in a couple of days.

‘Thumper,’ an Armi San Marcos Walker reproduction converted to fire metallic cartridges. The finish in the photo is an ‘antiqued’ treatment.

I had selected ‘Thumper,’ my ASM/Walker cartridge conversion for my first victi… uh… attempt. I completely disassembled the gun and began surface prep. The barrel, cylinder and frame needed to be done. I used 320-grit sandpaper to completely remove all trace of bluing from these parts, using small scraps of wood as sanding blocks where needed to avoid rounding off lines that I wished to remain crisp. The instructions recommended 320-400 grit for this; any finer and the solution might have trouble ‘biting’ into the steel. This entire process took about an hour; it’s a pretty simple gun…

Next I soaked all the parts in acetone as the first stage of de-greasing them. From the time they went into the acetone until the time it was finished I never touched it with bare hands again. I used standard surgical gloves from there on out, and went through several pairs. After the acetone bath I moved from the shop to the kitchen, where I scrubbed all of the parts with warm water and ‘Barkeeper’s Helper’ powdered cleanser. After that I rinsed them thoroughly and dried them.

The instructions recommend heating the parts to 150-200 degrees with a propane torch or other means. For my ‘other means’ I used our toaster oven. I allowed the parts to heat up, then removed them and applied the bluing solution. The directions specify putting a small amount of the bluing solution in a glass or plastic dish and working from that.  This is presumably to prevent contamination of the product in the bottle. I used cotton balls to apply it. 

It’s important not to overdo the application; whatever you are using as a swab should be damp rather than wet. I applied a thin coating to each piece and, with the parts heated to 200 degrees, they dried quickly. I treated each part and then replaced it back in the toaster oven. After three applications I immersed them in boiling water for five minutes. I used tap water for this, but tap water varies and you might want to use distilled water.

At the end of five minutes the parts came out and I patted them dry. They had turned dark gray. I removed the surface residue with de-greased OOOO steel wool. After only one treatment the finish was darker than I had originally used for this gun. I repeated this cycle two more times- three applications, allowing the parts to dry between applications, then boiling and scouring with steel wool before the next applications. After three cycles of treatment I was satisfied with the result, and per the instructions provided with the bluing solution I immersed the parts in a mix of baking soda in water for 30 minutes. Finally I thoroughly oiled the parts and re-assembled the gun.

Thumper after rust-bluing.

The case-hardened frame did not take as dark a color as the barrel and cylinder, but overall I am quite happy with the result. The total time invested in refinishing this gun, including disassembly, surface prep and re-assembly, was about four hours.

I subsequently treated the cylinders of two of my cartridge conversions with very good results, then did a full refinish of a S&W Model 1903 .32 Hand Ejector that I have been rehabilitating, and the results were excellent.

Pietta 1858 Remington reproduction, customized and converted to .450 Adams
Armi San Marcos Remington reproduction, customized and converted to .44 Colt (original)
S&W Model 1903 .32 Hand Ejector with custom target grips.

It would seem the key to attaining a good result with this product is simply following the given directions scrupulously, and avoiding touching the parts bare-handed after de-greasing. 

Bluing the two guns and the two cylinders used up the entire 4oz. bottle, and there is already another, larger bottle on the way. I can give it no higher recommendation.

Michael Tinker Pearce, 26 November 2018

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