Backyard Bluing

’ve I written several articles on alternative methods of finishing firearms but never covered traditional hot salts bluing. In this article I’ll discuss possible problems, start up costs, and an overview of the process so you can decide if this is a service you should offer. There are many alternatives to hot bluing giving hobbyists and small shops choices in finishing that don’t require the start up costs and hazards of hot caustic bluing.

Rust bluing, accelerated rust bluing (Dicropan IM), baking lacquers from Brownells and Lauer, and epoxy paints (Aluma-Hyde II) have their place and fill a need. Their main advantages are low start up costs, ease of application, attractive surface finish, and resistance to cleaning solvents This keeps the wind from dissipating the heat.

A cleaner without additives like Dicro-Clean No. 909 must be used to keep residue from the parts. as well as their ability to be used on alloys that would simply dissolve in a hot salts bath.

Their disadvantages include long cure times for epoxy finishes, looking like paint for most of the spray ons, labor intensive application (Dicropan IM), and extended application time (rust bluing.) As a shop owner or serious hobbyist sees his need to reblue guns increase from an occasional bluing job to bluing jobs backing up with preparation and labor time eating up shop time, it becomes necessary to streamline the process. The answer remains in hot salts bluing.

Unfortunately, the first hurdle for the cash-strapped hobbyist or small shop is start up cost. Anyone more than casually interested in gunsmithing knows that the tools of the trade are often specialty items made in small runs and can be expensive. A bluing set up is no exception. This overview of the process is meant to help make the decision if bluing is something worth adding to your list of services and isn’t detailed instruction.

For full instructions, Brownells publishes a 34 page booklet covering the subject in depth. Merely making a list of all the needed items to get started may be discouraging as there are many. Rather than overwhelm you with along list, look at the Brownells First Step Bluing Kit (082-000-006AK) with all the chemicals, hardware, and safety equipment needed, which retails for around $1,000 without tank stands. If you can build these yourself this kit puts you in business.

A professional set up including tank stands is the Bluing System Kit (082-005-007AK) for about $2,000. In addition to these kits, a source of gas (propane or natural) and water is also needed. Rather than getting discouraged by this initial outlay, consider how much work you have, how much can you get, and how long will it take to

make this pay for itself. According to the Brownells Shop Price Survey, labor charges for rebluing runs from $100 to $150 for a bead blast matte finish to as much as $250 for a masterclass bright blue finish. There are other considerations. First, you need a place to blue. You The ladle is used to add water to control the temperature of the solution and keep it in the operating range. This is where safety equipment is most important! The solution is extremely caustic and very hot.

It will eat through cloth, burn your skin, and dissolve aluminum. Avoid breathing the fumes! cannot blue in the house or in a shop with guns or machinery, The operating temperature fills the area with steam, heat, and fumes. The fumes alone will rust any unprotected metal in the vicinity and are not something you want to breath. Add heat and humidity to the equation and it’s clear a well-ventilated area with nothing around that can rust is needed.

I set up outside on my backyard patio, requiring set up and take down for each bluing session. Second, you’ll need gas to heat the cleaning and bluing tanks and your area may have city or state ordinances prohibiting outside burning of any kind. It’s far better to find out before purchasing equipment instead of when the police issue a summons the first time you fire up the system.

It took 30 minutes to get good color here. Time will vary with the alloy of the steel. Seen here in the boil-out tank, this removes salt residue from the parts and stops the bluing process. Afterwards, remove the parts, oil them, and let them cool. Proper due diligence demands checking local laws before. Once you’ve created enough customer demand to justify purchase and have an adequate work place, consider the process. While simple, it requires working very caustic, potentially dangerous boiling solutions.

Think of it as boiling lye that will strip your skin off in seconds and you won’t be too far off when looking into safety equipment and procedures. The system illustrated here uses the same propane cylinders found on backyard grills. The flowing cold water comes from a garden hose. With this set up, bluing is limited to nice weather with no precipitation. Overhead cover is needed with any chance of rain or snow. The tanks are set up counter clockwise with the hot water cleaning tank first.

The cleaner used must be free of additives that can leave a residue on the metal. Brownells includes Dicro- Clean No. 909 for this. Before placing the polished or blasted metal parts into the hot water tank, spray them down with degreaser to remove any trace of oil or grease from all surfaces including the bore. Putting an oily part in the cleaner is a bad practice. Although the cleaner will remove the oil, it can sit on the surface and a thin film may be deposited back on the part when it is removed.

If you find light spots on the part after bluing this is most likely the culprit. The parts to be blued are placed in the hot water cleaning tank for 20 minutes. Care must be taken at every step of the process to be sure the parts do not lay on the bottom of the tanks. Suspend on wires and never touch them with your bare hands. From the hot water tank they go into a cold water rinse.

This tank has cold water flowing into and out of it to remove all of the cleaning solution so upon removal the parts aren’t recoated with the solution floating on the surface. From the cold water rinse the parts go into the bluing tank having a boiling mixture of bluing salts and water. The parts are left in the bluing tank for about 20 minutes and should come out solid black with no spots or discoloration. From here they go into the hot water rinse to stop the bluing process, then are oiled and set aside to cool.

Simple as this sounds, there are little things that can cause problems. Wind may blow out the flame of the pipe burners and/or dissipate the heat enough to prevent the solution from reaching operating temperature. Wrapping aluminum foil around the tank stand and blocking the wind is a simple fix. Some alloys blue easily while others take more time. The time apiece is left in the bluing solution is determined primarily on how long that particular part takes to turn black rather than by the clock.

Strict application of bluing salt instructions results in a professional job with a minimum of problems. Additionally, Brownells has a staff to answer questions. Once the bluing session is over, allow the bluing solution to cool down to ambient temperature, cover the tank, and save it for the next session. If you keep the tank clean and don’t overheat the solution it can be reused. You will be periodically adding salts and water to the solution to control its temperature by controlling the ratio of salts to water.

That addition introduces new salts into the tank to "renew" them. Despite the start up costs, hot bluing remains the fastest and most economical way to blue firearms and is the reason why manufacturers still hot blue their steel parts. Consider the volume of guns you are bluing and decide how quickly the investment will pay for itself. AG