In order to save money, many make silver solders with their own hands. We will clarify the features of the technology, the options for using the finished alloy.
If you are not confident in your abilities, it is better to purchase ready-made pasta and not waste time on dubious experiments.
What is an alloy?
Pure silver is a soft metal, so it is not suitable for work. Mostly masters use mixtures containing zinc, nickel, aluminum, copper, cadmium. Silver solders, in addition to silver, include zinc and copper. A seam made using such a composition is strong and durable.
Compounds of silver, copper, zinc, have a high melting ability. They are used for silver solder. To control its percentage composition, GOST 19746 74 was developed. Solders, silver grades, are always indicated in the product instructions. The solder seam, which is obtained in a similar way, is durable.
Solder brand PSrMts 37
Silver solder wire (PSrMts 37 and PSr-25) is used to connect surfaces made of brass. The form for its manufacture is a continuous sheet. It is cut into strips 1.5-2 mm thick. The gaps between the surfaces to be joined are filled with silver solder capable of withstanding mechanical deformations and vibrations.
Chemical composition
The process technology is based on the use of silver solder designed for step soldering. Given that the solder must withstand temperatures up to 600 ° C, its components are: 33% cadmium, 30% silver, 16% zinc, 20% copper. The composition is quite fragile, does not withstand fluctuations. By increasing the amount of silver to 52%, a fluid mixture is obtained that can withstand multi-stage soldering.
Vintage recipe for cooking silver solder
Let's try to figure out how to make silver solder at home. There are several options for its manufacture, each with its own nuances. To get the alloy, you need a coin (fifty dollars) of 1924 , as well as five cents of 1962. For work you need: Ingus, silver, gas burner, spoon.
The production of silver solder begins with the melting of the precious metal. Then add a five-copeck coin. For complete mixing, the mixture is rolled on a spoon. The final mixing result depends on the duration of this process. The disadvantage of this technology is the burnup of chemical components that are needed for solder. Next, the master, creating an alloy with his own hands, pours it into ingus, rolls it without firing. The resulting solder has 900 samples. When soldering, it is necessary to prepare a fresh flux to guarantee the quality of work. The master monitors the flame in the gas burner so that the seam is smooth and durable.
Engineering works
For technical work, silver solders are used, containing up to 80 parts of silver, 16 copper, 4 zinc. Of interest are silver jewelry solders, the composition of which: 2.8 parts of brass, 7 - silver, 0.2 - zinc. Before starting work, brass is stripped from the oxide film. To obtain 10 grams of such solder, 999 silver samples are melted. Brass is added to the molten metal, mixed in a spoon. After complete melting, the mixture is combined with zinc, the resulting composition is rolled. Next, a sheet of rolled metal is cut with scissors, it is weighed on the scales. For effective work you need: a spoon, sandpaper, a gas burner, scales, folds, a spoon for mixing. Silver solders cannot be made without brass, silver, pure zinc, borax. For the manufacture of technical solder, silver of 94 or 96 samples is suitable. You can get such a metal by burning silver products: galloons, gimmicks, brocade.
Solder Melting
By melting the metals that make up the mixture, a silver solder for steel is obtained in the crucible. The gel is placed in the hearth, having prepared special equipment: a borax, a container of water, a coal mixture, an iron hook, a crucible. First you need to melt the refractory, and then add the fusible metals to the mixture. To make high-quality solder with your own hands, the work must be divided into two stages. First, the crucible is removed from the hearth, the metal is combined in a container filled with water. As a result, fine-grained drops of solder appear. They are dried, then re-melted, covered with brown. As soon as the metal is completely melted, it is poured into special forms. After solidification, the bars or tiles are rolled into thin strips. For subsequent use, they are cut on a lathe into thin wire.
Characteristics of medium melting compounds
What are homemade silver solders? Their properties are similar to those compositions that are obtained under industrial conditions. The resulting solders have high strength, corrosion resistance, low melting point, high thermal conductivity. During operation, the composition fills the entire space between the soldered surfaces, gives an even and durable seam. If you need to make an alloy of the PSP-72 grade, it is important to remember that when alloyed with lithium, the melting point with copper decreases. Such a composition is suitable for soldering steel parts resistant to chemical corrosion.
Solder preparation at home: features and algorithm
Soldering with silver solder at home also involves the reverse process - the transformation of a liquid metal into a solid state. First, it is important to completely melt the silver, then it is cast into ingus. All work is divided into three stages: making a spoon - a smelter, adding flux, placing a mixture in a spoon, melting the starting material, placing it in Ingus.
Place a small cardboard rectangle at the bottom of the spoon, then a slightly larger plate to wrap the edges of the spoon. Then quality sheets of cardboard are fried. The bed should be concave in order to achieve the desired result. The process of melting the solder at home is lengthy, so you have to be patient. Sorting of the charge is performed on jewelry scales. The master will need the following materials:
- jewelry electronic scales;
- 20 g of scrap of silver 916 samples;
- silver scrap 875;
- sterling silver (12 grams);
- borax;
- metal for solder;
- gas-burner
The whole mixture is divided into several piles of 18-20 grams. Silver and scrap 875 are mixed. For one smelting, approximately 6 grams of scrap and 42% of pure metal will be required. By magnet it is cleaned of iron impurities.
For the manufacture of solder take 875 silver and copper, the ratio should be 4 to 1 (you will need a silver fifty-fifty and three copper coins). For flux, a drill is used in a ratio of 1 to 10. Next, the flame is adjusted. Too much fire is not recommended, this will lead to the combustion of metals, and not their melting. Place a spoon over the gas burner. In the process of melting, the color of silver changes; it flows to the bottom.
Next, put the ingus near the flame to warm it. For high-quality melting, it is first lubricated with wax. Cooling and brilliance of the melt must not be allowed, this will adversely affect the technical characteristics of the solder. The liquid metal is slowly poured into the warmed ingus. Then let cold water. After complete cooling of the bar, they pull it out, turning the form for this. Asbestos or cardboard coating can be used for 3-5 swimming trunks.
Silver Repair
Beautiful chains, bracelets, earrings, forks, spoons, silver cup holders adorn a person’s life. But over time, products made of precious metal break down, need repair, restoration. To perform such work, silver solder is required. For 925 samples, you can do it yourself, using the advice of professional jewelers. For work, the following materials and tools will be required: ordinary and irregular soldering irons, casting for solder, scrap of silver. The easiest option for repairing a broken chain is to take it to a jeweler. But if you wish, you can cope with the problem at home, saving money. In order to solder silver on your own, you need to master the algorithm of actions, technological methods, study the physical characteristics of silver and its alloys.
Rules for soldering silver products
To perform such actions, it is important to have information on the physicochemical characteristics of the material. The melting point of silver is 960 degrees Celsius. From the point of view of jewelers, this is an average. For example, in copper, melting is possible at 1083 ° C, gold melts at 1063 ° C.
Depending on the components that make up silver, their temperature will vary. In order to accurately know the characteristics of the alloy, you can use the technical manuals. Marking of silver solders implies a sequence of Russian letters and numbers. The numbers indicate the percentage in the solder of the noble metal.
To repair a silver product, you need to prepare a soldering iron, clean the surface of the product. Silver solder allows you to make durable, dense seams that are resistant to corrosion. When repairing jewelry, use solder containing more than 70 percent silver, or a special paste for soldering.
At home, alloys of silver, zinc, copper, cadmium are suitable for repairing small jewelry. The optimal composition for "beginners" will be the following composition: 45 parts of silver, 25 - copper, 30 - zinc. The components are melted in a muffle furnace; flux is required. The finished mixture is poured onto a substrate, after cooling, it is passed through a milling machine to obtain thin sheets. Their thickness should not exceed 0.5 mm. For home soldering, you need sheets whose width is 1-3 mm. For home brazing jewelry made of silver, it is undesirable to use compositions containing cadmium. This metal causes serious health problems. The soldering point is exposed to air, oxides are formed. In order to prevent such a phenomenon, colophonium (flux) is used in home soldering. When melting silver solder, it is important to monitor the uniform distribution of flux on the work surface. If you have doubts about your skills and theoretical knowledge of the soldering process, it is better to contact a professional jeweler.
It is not recommended to use compositions containing cadmium at home, since it evaporates negatively and negatively affects health. To prevent the oxidative process and other negative reactions, flux (colophonium) can be used. It is important that it is evenly distributed over the surface of the metal.
Conclusion
Soldering silver will require special skills and courage from the master. The desired result is possible only if the correct flux, silver solder. Silver scrap is not suitable for home repairs, since the melting point will be lower than that of the item being restored. Compositions having an equal melting index with pure silver are not suitable for work. This will cause the flow of solder during melting.