| Start section
Model aircraft, model aircraft
| Tricks to master
| Secrets of the cosmos
Secrets of the Earth
Secrets of the Ocean
|The use of materials from the site is permitted provided the link (for sites - hyperlinks)|
TECHNOLOGY OF TREATMENT OF THE METAL SURFACE
The iron products to be polished are immersed for some time in a mixture consisting of 1 part of sulfuric acid per 20 elements of water capacity, then the object is removed, thoroughly rinsed with water and also dried in sawdust. After drying, it is immediately immersed for one or two seconds in nitric acid, after which it is rinsed again with water, again dried in sawdust and then also thoroughly wiped. In this case, the surface of the object becomes bright, as if the glass. Only the above method can achieve such perfect polishing.
Final finishing of plumbing products
To give the plumbing products a great view, they resort to various means depending on the nature of the work. Small artistic forgings take on a beautiful view, if at the end they are supplied with an intense black color. But for such works, the paint is not applied by smearing, however, the following operations are carried out: the flame in the furnace is lit according to the size of the item being processed. The fire should not smoke in any way (it is best to consume coke for this). Then the object is smeared with ordinary linseed oil and is also subjected to the action of a flame, but only for a time until the oil evaporates and the remainder does not burn it to the gland. After cooling, wipe the object firmly with a cloth lightly soaked in linseed oil.
The smoother the surface iron received during processing, the more beautiful the deep black color will look. This color is extremely durable and also perfectly protects against atmospheric influences.
To pickle the iron elements in black paint, they must be clean, brightly straightened and polished. Then they are smeared with liquid oil and sprinkled with wood ash, and then they are held over hot coals, until you get a runny black color. After cooling, the objects are washed in water, to which a few drops of sulfuric acid are added, and immediately wiped thoroughly with a coarse, clean cloth. Rubbing with oil protects the product from exposure to air. In order to make iron especially soft, it is heated red hot, is hastily cooled in soap, heated again until scarlet heat and put in a lime powder, allowed to cool slowly. When it is finished in this way, iron is made very crumbly and soft.
Cleaning copper items is done as follows: first polished copper items are wiped first with a soft cloth moistened with kerosene, but then cleaned with a wool cloth with chalk powder. "Viennese" lime. heavily fueled copper objects give off shine, wiping the object with a cloth moistened with dilute hydrochloric acid. Then clean, as if stated above, or dissolve 30 g of oxalic acid in 1 liter of water, add 4 tablespoons of alcohol and 3 tablespoons of turpentine. After that, the liquid is well shaken and bottled for storage. When used, the object to be cleaned is slightly wiped with this liquid, but then it is wiped with a dry linen cloth: the copper is quickly cleaned and also becomes shiny.
Cleaning nickel items
The nickel objects to be cleaned are first moistened 2-3 times with a mixture of 50 elements of alcohol (or vodka) and 1 elements of sulfuric acid; then they are rinsed with water, plus, washed with alcohol (or vodka), wiped with a thin linen cloth.
Rust on nickel is removed as follows: lubricate the object with some grease and leave it for several days, then wipe it thoroughly with ammonia. If the rust has penetrated deeply, you can take diluted hydrochloric acid instead of ammonia, which, however, is left on the metal for no more than a minute. Then the object is washed with water and polished with chalk and crocus.
A simple and good composition for this purpose can be a paraffin and oil mash. In the bottle on 20 elements of oil add 1 share of paraffin, carefully shake up the filled blooming of paraffin plus, after wiping the object to be cleaned, cover it with a brush with this mixture; then left for 10-12 hours in the room, protecting from dust, after which the object is wiped with a dry wool cloth. If a steel tool or other object requires more thorough cleaning due to significant rust, etc., then use the following composition: prepare a mash of 5 elements of turpentine and 25 parts of stearin oil.
This mixture is diluted with alcohol until a viscous liquid is obtained, which also covers the object, and when the alcohol evaporates, the metal surface is rubbed with a mixture of 45 parts of animal charcoal and 25 elements of powder in the powder.
Iron stamping also steel
For stamping steel products (tools, etc.) usually use caustic acids, which, however, represents a lot of inconvenience, not to mention the fact that also the label itself turns out to be not at all elegant. The following method in all respects deserves preference. First of all, a solution is prepared in 400 g of water of common salt (86 g), copper sulphate (86 g), zinc vitriol (24 g) and ordinary alum (12 g). Then they take a piece of unsophisticated soap, moisten it with water and rub it into the room of the steel object on which they want to make a mark. At the same time, they pay attention to the fact that the rubbed place is covered with an even, not very thick layer of soap; later, with some sharp object — an awl, a nail, or the tip of a knife — the desired label is scraped on the soap layer so that the metal surface is clearly exposed. Now it remains only to fill the recess obtained in the soapy layer with a few drops of the above solution and also leave the object in this form for a few minutes. If you then wash the layer of soap with water and wipe the object dry, then a beautiful copper-colored mark will clearly appear on its steel surface.
For etching the inscriptions on iron or steel products, mostly diluted nitric acid (15–20%) is used; For the application of acid to a metal object is a rubber stamp, but only made of much more hard rubber than ordinary stamps for paints, which is achieved by a longer process of vulcanization. In order to get a distinct etch of a letter, stamps should be as clear as possible and thin. Instead of a pillow, a piece of glass is used on which a piece of cloth is put. On the final poured so much acid so that it is fully soaked, also to him tightly pressed stamp. After that, lightly apply the stamp to the metal to be etched, and leave the object for a long time, but then wipe it with kerosene, however, to prevent rust formation, use bone oil.
For applying on a smooth brass surface durable inscriptions are not suitable commonly used paint for stamps. For this purpose, so-called "mordants" are needed, which are pre-applied either on a glass plate or directly on a clean cushion for stamps. Actually stamping can be made with ordinary rubber stamps.
"Mordants" consist of a solution of the chloride salt of a metal; for example, a mixture of equal parts of copper chloride and bismuth chloride alienates a good imprint. For this purpose, both salts are washed together in a porcelain mortar, and they are also diluted with dissolved hydrochloric acid in a tightly closed bottle. It is possible to jointly erase part I of mercuric chloride with 2 parts of antimony chloride by adding slightly hydrochloric acid to the mixture, and the result is a liquid suitable for stamping.
Transfer of engraving patterns to metal surfaces
We advise you to take a drawing, which is desirable to translate, also make a reverse drawing from it (through the glass). Then cover the metal surface with a weak aqueous solution of gummigut (yellow water-color paint), put a reverse image on the dried surface and also smooth it with a smooth object (agate or just with a thumbnail). The contour made with lead pencil is clearly transferred, and the image can also be engraved with a needle with a graver.
Cleaning metal parts of machines
We give the best way practiced now in France for cleaning metal parts of various machines. To one liter of kerosene add 10% paraffin plus, well plugging the vessel, leave it for a day, shaking from time to time, after which the mixture is ready for use. Then, using the cloth, it moistens all the metal elements of the machines to be cleaned. After wetting, they leave it in this state for the night (or even better for a day) and only wipe it dry with a clean cloth only the next day. With this method of cleaning, rust, greasy resinous ooze, etc. and the metal elements of the cars seem to be re-polished. In no other way is it possible to clean them so well, not to mention the extremely low cost of the method itself, which makes it quite suitable for this purpose with respect to each kind of machine, tools and common products made of steel and polished iron.
Iron protection against rust
Protection is true if the surface has been well cleaned beforehand. The following remedies are recommended:
1) Coating with substances that absorb water as well as acids or bind them. So, to protect the boilers from rust on ships, a solution of zinc oxide in caustic sodium or solid carbon dioxide of zinc is added to water. In addition, when they are suspended, steam boilers are filled with lime milk or soda solution. It is better to place in well dried (with the help of the firebox) potassium chloride boilers with the size of a nut while simultaneously stopping the access of air. In tunnels, limestone crushed stone is used to protect iron from rust, or iron parts are covered with limestone milk; By this, binding is also achieved by neutralizing a very harmful rust-producing element, namely sulfurous acid in the flue gases of steam locomotives. Nuts in the tunnels are twice covered in tar.
2) The metal coating is made after preliminary etching in acid and after haste drying in a hot condition; the objects are immersed in the expanded metal or are galvanoplastic coated in an appropriate metal bath.
Zinc is the best preservative (also in seawater), since iron alloy with zinc is always formed on the surface of iron in a zinc bath. Galvanized iron in trade is often found under the name of galvanized. Better cold electrolytic zinc.
Tin protects weakly also only until the iron is not exposed anywhere.
Lead protects from hydrochloric and sulfuric acids: sheets coated with lead are used to cover the roofs of organic, gas plants, etc.
Copper (galvanic) also protects nickel only with a considerable layer thickness.
3) Enameling. The surface of the iron casting is etched and also dried, but then it is coated with a powdery primer (feldspar, quartz, auger and clay), fired before casting and then coated with enamel (silicates with tin oxide) is also heated until the enamel is melted.
4) Fats in solid or liquid state are very convenient for coating cleanly finished surfaces of machines up to assembly. In the open air fats are washed away by a shower or drain from the action of sunlight. Fat with an admixture of 50-100% lead white white seems to bitterly: fatty acids formed from the breakdown of neutral fats corrode iron. A mixture of talc and graphite is recommended for lubricating wire ropes (once a month). Recently, mineral fats dissolved in turpentine or in lightly volatile products of kerosene are often used.
5) Portland cement not only protects against rust, but absorbs rust that has already formed on the surface of iron (Monnier structures). Cement seems to be an excellent medium for large castings as well as impressive iron structures. Finely sifted, diluted in water, cement is applied with a brush on metallic clean surfaces. The coating is repeated from 4 up to 5 times after the final layer has hardened. For surfaces exposed to water (sluices, bottom of vessels), the smallest cement is mixed on skimmed milk.
6) Tar, asphalt and resin in the anhydrous state serve as a good coating for cast iron pipes. The resin also pipes are preheated.
7) Coating resin oil. Rubber oil: a solution of rubber in turpentine oil. Antioxidation is an impotent solution of gutta percha in gasoline.
8) Rubber and celluloid allow excellent coating for nails, screws, buckles, rings, etc., and these elements at the time are not exposed to air, water, acids. It is quite proud for electrical insulators. It is recommended to cover ship shafts with hard rubber. Parts of cars on vessels of deep navigation are covered with a solution of celluloid.
9) Oil paints are most commonly used. Boiled flaxseed oil lags behind easily; It is better for sizing to take liquid, hastily dried linseed boiled oil mixed with graphite, ocher, iron red lead (no more than 20% clay) or better with lead red lead. Under water, only lead red lead has proven itself well. After sizing, the actual coloring is carried out, for which pure boiled linseed oil is taken with lead white (and not zinc), graphite, zinc dust, and with the addition of chalk. In order to avoid the formation of bubbles, another layer is applied only after the final hardening of the previous layer.
Protection of silver items from tarnishing
It is known that silver-like as well as silver-plated things dim relatively quickly in the air also take on an ugly look. To eliminate such tarnishing, the following remedy is recommended: prepare the liquid solution of the collodium and also smear this solution with a thin layer of silver or silver-plated objects with a thin layer; Alcohol hastily evaporates also on the metal surface remains a thin, completely imperceptible for the eye of the collodium film, perfectly protecting silver from tarnishing under the influence of the atmosphere or gases in it. As shown by experiments made in museums abroad, silver, covered with a thin layer of collodium, permanently retains its paint, the shine is also polished. If necessary, this refined safety layer can be easily removed with hot water.
Ingenuous means of tinning
Take 10 weight elements of sodium chloride, dissolve in 20 parts of nitric acid, after which 10 parts of tin chloride (tin salt) and 2.5 elements of ammonium chloride (ammonia) are added to this solution. An additional 40 parts by weight of hydrochloric acid is also added to the mixture, then also diluted with a small amount of water. The mash prepared in this way is quite ready for use. The object to be tinned is forced to be pre-cleaned very thoroughly, then all parts of it that should not be covered with half a day are carefully rubbed with lard, after which the object is immersed in the mixture prepared in the above manner, in which it is left until the half-day layer reaches proper thickness. Then, removing the item, it remains only to thoroughly wash it so that it is completely usable. In addition to fixing or updating the noon on the dishes in the indicated manner, it is possible to cover with tin with tin to protect from rust various small metal objects: fish hooks, traps, wires, etc.