Cold Bluing Vs Hot Bluing
From Pine Beach NJ: The world's most popular metal finishing website, and the internet's friendliest cornertopic 12361 HOT OR COLD BLUING METHODI AM IN THE PROCESS OF BLUING SOME OUL HAND GUNS AND NEED TO FIND OUT THE BEST BLUING METHOD. WHICH IS BETTER, THE HOT BLUE OR COLD BLUE METHOD AND EQUIPMENT NEEDED OFR BOTH.MANY THANKS, DAVID LURER- CAPE CORAL, FL, U.S.A.You may want to look in google groups rec.guns an append with the title: Anyone tried this homemade hot bluing formula?The hot bluing with ammonium nitrate and lye are described there. I will experiment with it one of this days.To the forum moderator: Not wishing to go against the rules I have not posted the web address of the append I mentioned above. Why is this so?'
Don't include phone/fax/e-mail/website addresses in this text block.' Thank you very much for your patience. Aquiles Rubina- Lima, PeruLeadsetter's Note: Yes, Mr.
Rust Blue Vs Hot Blue
Rubina, thank you for reading and following our posting guidelines. Our website has commercial links for finishers. Rance allen/i'm not givivg up. The income from advertising is our only source of revenue, which makes this site possible.For that reason, we cannot print 3rd party solutions or URL's.Thank you, and please mention our site to companies who may be interested in advertising at finishing.com. We have many satisfied customers who get an extremely high return on investment for their directory listings.
For more information, please visit www.finishing.com/yournamehereTom PullizziSecretaryfinishing.comEd. Note: Another problem is that these 50,000+ topics and their responses are a resource that remain on the net for years, even decades - long after most of the referenced e-mail addresses and area codes changed. Countless URLs that were once technical content have been sold and redirected to commercial sites. On some of our early letters I and others recommended URLs which, due to spamming of newsgroups, have now degenerated into little more than directories of get rich quick schemes and pick-your-depravity porn sites. Maintenance of our site proves impossible if we are not very careful about links to other sites scattered over 50,000+ pages.You will probably not be happy with a cold blue. It will not hold up very well and is a lot of work to obtain a good finish. I use a commercial caustic soda solution at 300 deg.
If you only have a few guns to do, you will be ahead to find a gunsmith in your area to do the bluing. You would need tanks, heat source, safety equipment(most important), rinsing tanks, etc.
As was suggested, a search of 'gunsmithing supplies' on the net would turn up sources for bluing salts, equipment, and most needed, instructions.Good luck, Ed Kay- St. Louis, Missouri, USA2007Hi David, hot bluing is the most simplest method to blue your gun.here is how you do.1.clean and remove all pits and rust using emery sheet 400,followed by emery 800. 2.if possible buffing can save lot of time and energy. 3.make sure you have no finger prints or dust.
4.use a news paper to hold the parts and wipe clean. 5.mix 1kg of sodium hydroxide(caustic soda)with 1/4 kg sodium nitrate and add 1/4 liter of water.
6.heat the above mixture to about 140 degrees, 7.dip the parts in the mixture for about 10 minutes. 8.leave the parts in the mixture till the temperature comes down to 80degrees. 9.take it out of the mixture clean immerse in hot water,this will remove the chemicals stuck to the metal. 10.apply oil. First try this with a small parts,good luck. Dr.N.Jayakumargeneral surgeon - IndiaIf you have a question in mind which seems off topic, please.
Browning and bluing are terms used to describe any of several chemical treatments of metals that are essentially controlled rusting processes. On ferrous metals, bluing appears as a dark-colored, protective oxide layer on the surface.Probably the earliest surface treatment for metals was browning.
Cold Bluing Vs Hot Bluing Products
The procedure was popular with early gunsmiths, and by 1700 the process was understood and used by most. The process was understood and used by most. The process begins by dissolving ordinary table salt in distilled water. The parts to be browned are cleaned, polished and thoroughly degreased.
If a gun barrel was being browned, the bore was liberally coated with grease and plugged at both ends with tapered wooden dowels. Next, the saltwater solution was liberally applied to the surfaces to be browned, and the parts left to stand in a humid environment. Within 12 hours or so a thin coat of rust formed. The parts would be lightly rubbed with degreased, fine steel wool to remove the loose rust, leaving a slightly colored surface. The parts were then recoated and returned to the humid environment to allow further rusting. The cycle of rusting/rubbing-rusting/rubbing was repeated until the desired shade of brown was achieved.Cold rust bluing is a similar process.
A solution of hydrochloric and nitric acids diluted in distilled water with a small quantity of iron filings added is prepared. As with browning, the parts to be blued are polished and degreased, the exposed surfaces swabbed with the bluing solution, and the part left to stand in a humid location. After 12 hours, the loose rust is rubbed off with degreased steel wool or a stainless steel wire brush, the surface is recoated with bluing solution and the part is returned to its humid environment. The process is repeated until a deep blue finish is achieved—which may take from five to 10 days. Although a very slow process, cold rust bluing produces a deep blue color generally considered to be the most durable kind of bluing. Like browning, it can be used on side-by-side or over/under shotguns with barrels joined by soft solder, which would be corroded by hot bluing solutions.By contrast, hot-water bluing processes can produce a deep blue finish in just a couple of hours, rather than several days.
Hot-water bluing uses a bluing solution containing potassium nitrate, sodium nitrate, potassium chlorate and mercury bichloride that is applied by hand to a clean steel surface that has been heated by immersion in boiling water. After applying the bluing solution, the part is immersed in the boiling water for five minutes, then re-coated with bluing solution. This cycle is repeated, with loose rust being rubbed off with degreased 0000 steel wool, until a rich blue-black color is achieved.Hot caustic bluing is a fast metal-treatment process suited to high volumes.
Consequently, it has become the preferred method for bluing by most gun manufacturers today. In this process, the clean metal parts are immersed in a solution of sodium hydroxide salts heated to about 300 degrees Fahrenheit.
Midway through the immersion period, the parts are removed from the bluing tank, rapidly chilled in cold water, then reimmersed in the salts to promote a a deeper final color. Finally, the blued parts are removed from the salt solution, washed in boiling water to remove all traces of salt, and coated with water-displacing oil. Hot caustic bluing cannot be used on non-ferrous metals, such as aluminum, magnesium and zinc, as they will dissolve and contaminate the bluing salts.Heat bluing is a process often used for finishing small parts, such as pins, screws, triggers and hammers. In this method, the parts are heated to 600-700 degrees Fahrenheit in a propane flame or burning charcoal, then immersed in oil. A variant of this process involves heating the part in a bath of molten potassium nitrate, then dipping the parts in water.
Rust Bluing Vs Hot Bluing
Heat bluing produces an attractive deep-blue finish, depending upon the heat and the metallurgy of the part. However, this process is not suitable for large parts due to the difficulty of producing an even shade of blue throughout.Cold-bluing solutions usually work through the chemical actio of selenium. The finish produced is not as durable as other blued finishes. For this reason, cold blues are not suited for bluing large parts or entire guns. However, cold blues excel for touch-up work to hide nicks, scratches and blemishes in existing blue finishes, although they may not match the existing bluing perfectly.Do note that stainless steel is impervious to most bluing solutions, including instant bluing products.