Thoroughly clean the articles in ammonium sulfide, and hydrochloric acid for a few minutes will lightly etch the surface and create a light rusted effect which will improve the depth and darkness of the finished. The caustic tank has to be mild steel, stainless steel tanks for the salts will give a ugly bluing color. True gun bluing is an electrochemical conversion coating resulting from an oxidizing chemical reaction with iron on the surface selectively forming magnetite fe3o4, the black oxide of iron. In order to put a hard layer on the steel, carbon must be fused at the molecular level into the top centimeter or so of the steel. Heat bluing or flame bluing is actually heat treating. It also works best on steel that has been nearly mirror. If i have to touch the degreased area with my hands, i wear rubber or vinyl gloves to prevent moisture and oils from my hands getting on the bare metal. Another option for bluing gun parts is to use a blowtorch instead of a hot salt solution. The blueblack image of black iron oxide is what gives the name to this process. Simply clean and oil the steel, then heat the metal until it changes to the color youre looking for. Black oxide formula for hot blueing of gunsfirearms.
This video shows how to blue steel parts using an oven or torch, and quenching in oil. How to blue bluing steel using oven or torch and oil method duration. Supplies will be bluing salts, metal parts cleaner, steel wool, scotch brite pads, and wd 40. Submerge the treated parts in the bath of waterdisplacing oil. The process in hot salts converts the ferrous metal surface into a black iron oxide compound called magnetite fe3o4. Smith wesson hired the american gas furnace company to develop a bluing oil that included special whale oil. The tempature will depend on the type of steel, the finish on it, polish or blasted and the type and weight of oil you use. Wear nitrile or latex gloves to keep this oil from reaching. As i remember regular bluing is a complex of ferocyanides. True gun bluing is an electrochemical conversion coating resulting from an oxidizing chemical reaction with iron on the surface selectively forming magnetite fe 3 o 4, the black oxide of iron. Bluing is a passivation process in which steel is partially protected against rust, and is named.
Its actually called oil blueing and is a way of protecting the steel from rust and corrosion, i have most often seen it used in the manufacture of firearms. Special note about bluing effect on bores and rifling. The guns were put in a rotating drum loaded with wheal oil and charcoal, and the drums were warmed in the oven while the oilcharcoal mix rotated around the parts inside the drum. How to polish bluing without rebluing the high road. A discussion started in 2001 but continuing through 2020. However ive never heard of heating the metal and dunking in oil. The buffing should be done dry and the surface and the steel wool should. The blue shine is due to additional chemicals such as manganese that are added to the mix. I found through my bluing adventure that different oils do act slighty different but ultimately everything ive used has done the job. How to colour steel with heat hot oil finish is a simple but effective way of achieving a desired colour of choice. Stock sheen and conditioner, fine, medium and coarsegrit garnet papers, 00 steel. Hardening steel with motor oil is a way of performing what is called the case hardening of steel. This science can be applied to bluing steel as well.
Model engineer recently had a writeup about blackening steel by heating it to a dull red and dropping in oil. Other tanks are cold water rinse, hot water rinse at 200 degrees, neutralizing bath at 140 degrees, and water displacing oil bath. Select gun oil designed to create a thin coat across the surface of the bore and seep deeply into the pores of metal surfaces to protect your firearm from wear, humidity and moisture. Ive been searching for historic documentation of charcoal bluing of gun barrels in the 18th century, but come up emptyhanded. Durability the finish seems more durable than cold bluing, just because you have a. The equipment the bluing tank can be welded up using plain sheet metal. The longer you apply the solution, the blacker it will become. The excess rust is removed and the process is repeated until the desired finish is required. Bluing a stainless steel barrel im on the verge of purchasing a colt 1991 and was wondering if it was possible for a competent smith to blue just the barrel, or if i would have to order an unfinished barrel to be blued. The steel will pull some of the carbon out of the oil while quenching and harden the outer portion of the metal. If you have enough solution, and your piece of steel is small enough, you can submerse the steel into the solution. Regular steel will take on blue and bores will look dark. Jun 01, 2014 heat bluing or flame bluing is actually heat treating. Essentially, rust bluing uses an acid solution to rust the steel in a controlled environment.
My friends at colonial williamsburg do it but cant seem to provide me with an answer as to evidence. Hi eric, i have an old engineering book dictionary of metals and alloys 1939, which describes the hot blueing process very well and safely and i have used it with good success. The first step is to remove the old finish and rust, so the gun is blasted with a fine glass bead, which. Liquid bluing is a colloidal suspension of a very fine blue iron powder and water. Probably not as good as the salts, but cheap and not dangerous. Sep 02, 2008 the caustic tank has to be mild steel, stainless steel tanks for the salts will give a ugly bluing color. Also the chemical composition of chemical degreaser alkaline. I ask because im interested in bluing a carbon steel mora. The bluing process is often accelerated and intesified with the use of heat. Steel will turn a rainbow of colors as it is heated and if you remove the heat at the right time, you can get a nice electric or peacock blue color, just like nitre bluing. Bluing or black oxidizing is a process of treating steel to create a thin protective shell around it.
Warm steel will take bluing faster and often deeper than cold steel. Apply some gun bluing solution to a clean piece of cotton cloth or a toothbrush, and rub it onto the surface of the steel. Bluing is a passivation process in which steel is partially protected against rust, and is named after the blueblack appearance of the resulting protective finish. Oil blackening is a very old process used before the chemical treatments. Your hands will leave oils on the metal that interfere with the bluing process. It is much more consistent and deeper than cold bluing or using a torch to heat blue at least for most of us. The cold bluing solutions usually are sold in little bottles and are applied with a brushtype applicator. Chromed bores will not be affected same as stainless. Neither of these are bluing even a blue oil finish. Some people advise to plug them to prevent this, others say its unnecessary, since first 23 rounds shot through that bore will strip bluing clean and youll have a shiny bore again. Nov, 2016 remove the steel from the pot, then oil and clean. Youll need a sander, alcohol wipes, wax and grease remover, bluing solution, cotton balls, sandpaper, a soft cloth, and gun oil. There is something really rewarding about this technique.
At first a thin coating of oil was used to prevent corrosion in iron and steel, but eventually bluing processes were invented to provide much better protection. Some hardened and specialized steel alloys may blacken to a deeper black finish when activated using our black oxide activator. Homemade hot blue formula original post courtesy of blair emory my comments in brackets km all bluing is really blacking. Bluing can also be used as a blue dye to darken jeans and other dark blue fabrics. Blackening not only protects bare steel from rusting, but the process also yields a relatively attractive finish.
First, youll need to grind and sand your steel down to remove any finish and make it smooth. All things become more pliable and receptive to change when they are heated. How to blue bluing steel using oven or torch and oil method. Im making a simple tapping tool and want to give it a black. This is a traditional process that is still used on highdollar. Keep all the moving parts of your firearm in smooth, working order with gun cleaning oil and gun cleaning lubricants.
True gun bluing is an electrochemical conversion coating resulting from an oxidizing chemical reaction with iron on the surface selectively forming magnetite, the black oxide of iron. Diy gun bluing stepbystep walkthrough tactical guru. Boiling the rust converts the red oxide to black oxide which constitutes the metal finish. The bluing process on steel is a true conversion coating, meaning that the surface has been changed into something else. What you are describing as hot oil bluing is also known as lamping it works great on small parts where you can control the heat in the metal and keep it even thru out the part. Had a m15 awhile back, and i used whatever was available at the time over the years, but i do recall on one side of the gun, the bluing was of a slightly different hue as compared to the other side. Bluing is an electrochemical conversion, where the surface of the steel is converted to a form of controlled rust called magnetite fe3o4. How to turn steel black all you need to know about bluing duration. Oxides of iron are red and black, brown rusts are hydrated oxides. A brazed chain however suggests youve got brass and steel which will not finish evenly.
Not only does it give you an alchemical feeling of satisfactionbut it also gives the metal a. It does provide good rust resistance, which is improved with oil. Blacking with heat wont have the same effect on both metals. Bluing is a chemical change to the surface, brought about by supplying more than just oxygen. Apparently if not black enough it could be repeated with a bit higher temp. The art of bluing steel has been used with firearms since the very beginning, but bluing is much older than firearms. But, the oxides from the fecl cause the steel to become a uniform, deep blue. Im wondering whether it would be beneficial in helping prevent rust on an already oiled blade, and id like to know if bluing has any drawbacks whatsoever. I use straight 30 weight non detergent oil for small parts that i lamp rather than bluing. Temper blued barrels, and the process of doing so however, is documented. Before bluing a part it must be thoroughly degreased, otherwise the bluing wont take.
Bluing steel is the process of oxidizing the surface to protect it from rust. This creates a very durable finish for interior use. It comes out all funky colors with bluing and lamping on the same part. Black oxide works on steel or iron parts only and will not blacken stainless steel use stainless steel blackener. Pure steel is actually too soft for many applications. The oil prevents the formation of rust and protects the metal finish from sweat, body oil, wear, and dirt. Theres a bit in trustee from the toolroom about a trick to blue small bits like this.
The buffing should be done dry and the surface and the steel wool should be dusted off frequently to avoid any buildup of rust particles. Apr 25, 2012 special note about bluing effect on bores and rifling. Bluing is a process usually used by gun owners and firearms manufacturers to improve the aesthetic value of their weapons. Equal parts beeswax and boiled linseed oil brush on clean, hot steel with a natural bristle brush is the standard for blacking. Regular oil is best, not synthetic or detergent oils. Other ingredients include a ph balancer and a biocide to prevent the buildup of algae and bacteria. Black oxide provides minimal protection against corrosion, unless also treated with a waterdisplacing oil to reduce wetting and galvanic action. Oxides of iron are red and black, brown rusts are hydrated. The colours are fantastic and often come out in a beautiful twotone shine. Cold bluing solutions are technically made for touching up scratches on already blued steel surfaces, this bluing can also work well to finish larger areas. You can achieve this finish with some pretty common household items. It does provide rust protection and the film is very tough.
I use acetone and a qtip to degrease the area to be blued. This method is not the professional method using bluing. Trick for bluing small parts but the originals are blacked and i felt queasy about putting a bare steel one in place of the original. The coloring action happens instantly and the color penetrates deep into the metal for a longlasting finish.
Some of the oldest examples appear in ancient japanese swords. But it is not meant to try and touch up worn parts. It provides the steel surface with a layer of protection against rust and corrosion while reducing potential glare as well. Gun blue fx is like any other cold bluing solution, and like the little bottles of gun coldbluing for fixing scratches or rubbedworn spots on a blued finish firearm, requires several wet, rinse, reapply cycles to get the depth of gunbluing color shown in the photo below. They are usually less abrasion resistant than blacking and perforce are thinner to give the blue refraction. How to blacken steel with motor oil with pictures instructables. Birchwood casey deluxe perma blue bluingstock finish kit. For most of the time, guns that utilize carbon steel components are the prime candidates for bluing but its totally possible to blue stainless. While there are a few different types of bluing, one of the most durable forms is hot salt bluing. I want to know the exact composition of the bluing salt used for the bluing of m. This was the first time that i ever used cold bluing on my fabrication projects.