Several ways to make blue-writing at home
Burning, or oxidation, it became knowna long time ago. Previously, this treatment was used to protect the metal from corrosion, now - mostly for decorative purposes. For the skilled craftsman it will not be very difficult to carry out the bloom at home to give the metal product an interesting look or to restore the hunting rifle. For this, only desire and certain knowledge are needed.
Ways to make blueing at home
The simplest of them is the coating of metal with oiland the subsequent heating. This is done as follows. The workpiece is cleaned and degreased, after which it is rubbed with a thin layer of drying oil (can be vegetable oil). Then it is placed in a oven or a conventional oven and heated to four hundred degrees. The result is a strong decorative film of a dark brown hue.
Another way to accomplish bloom in domesticconditions is the cooking of metal blanks in a strong alkali solution (potassium, sodium hydroxide). In this case, the metal acquires a beautiful blue hue, but the blueness is not very pronounced - easy. Therefore, this method is more suitable for small-sized metal objects of cylindrical shape. To obtain a more pronounced blue-black hue, the billet should be boiled in a solution consisting of 1 liter of water, a quarter kilogram of sodium nitrite, 700 grams of sodium hydroxide and 200 grams of sodium nitrate.
The most difficult way to make the bloom inhome conditions, but also giving the best results - the digestion of the billet in the melt of sodium nitrate. The process should take place at a temperature of 350 degrees Celsius. This way you can get a very strong, beautiful bluish tint oxide film.
Burning of gun barrels
All of the above described ways to make a bloom inhome conditions are of little use to restoring gun barrels. For such work there is a special composition, which can be purchased in specialized stores. In case there is no such tool in available shops or for some reason its use is undesirable, here is a good way to implement the blasting of trunks at home.
As a container, a stainless steel pipe of the appropriate diameter and length is used. One end of the tube is brewed.
1. The trunks, with the help of abrasive materials, are cleaned from rust and old bloom, after which they are polished with a felt wheel.
2. From both ends, the trunks are closed with stoppers resistant to chemical reagents. The surface of the billet is degreased in two stages. First, just rubbed with gasoline, and then the trunks are immersed for twenty minutes in a solution heated to 70 degrees. The composition of the solution is as follows: one liter of water, 50 g of sodium hydroxide, thirty grams of soda ash, the same amount of sodium phosphate and 5 grams of silicate glue.
3. To remove the old oxide film, decapitation, or weak etching, is used. The trunk is dipped in a five per cent solution of sulfuric acid and held there for one minute.
4. The main process occurs with an aqueous solution of orthophosphoric acid (0.7 / 100), ammonium chloride (6/100), sodium hyposulphite (8/100) and nitric acid (0.3 / 100). The trunks are "cooked" at a temperature of 70 degrees. In one hour.
5. To fix the obtained oxide film, the billet is immersed for five minutes in a solution of chromium (120 g per liter of water). The temperature of the solution is 70 degrees.
After the procedure, the bluing of metal in the homeconditions is completed by thorough washing of the trunks, and in no case can they be taken with bare hands. Special attention must be given to safety measures with each treatment method! All substances are very aggressive!
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