To save money, many people make their own silver solders. Let's find out the features of the technology, options for using the finished alloy.
If you are not confident in your abilities, it is better to buy 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. Basically, craftsmen use mixtures that include zinc, nickel, aluminum, copper, cadmium. Silver solders, in addition to silver, include zinc and copper. A seam made with this 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 joint obtained in this way is strong.
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 solid sheet. It is cut into strips 1.5-2 mm thick. gaps betweenthe surfaces to be joined are filled with silver solder, capable of withstanding mechanical deformations and vibrations.
Chemical composition
The technology of the process 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 vibrations. By increasing the amount of silver to 52%, a fluid mixture is obtained that can withstand multi-stage soldering.
An old recipe for brewing 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 will need a coin (fifty kopeck) of 1924, as well as five kopecks 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 a five-kopeck coin is added. For complete mixing, the mixture is rolled over a spoon. The final result of mixing depends on the duration of this process. The disadvantage of this technology is the burnout of chemical components that are needed for solder. Further, the master, who creates the alloy with his own hands, pours it into the Ingus, rolls it out without firing. The resulting solder has a 900 test. When soldering, fresh flux must be prepared to ensure the quality of the work. The master is watchingbehind a flame in a gas burner, so that the seam is even and strong.
Technical work
For technical work, silver solders are used, containing up to 80 parts of silver, 16 copper, 4 zinc. Jewelry silver solders are of interest, the composition of which is: 2, 8 parts of brass, 7 - silver, 0, 2 - zinc. Before starting work, the brass is cleaned from the oxide film. To get 10 grams of such solder, 999 silver is melted. Brass is added to the liquid metal, mixed in a spoon. After complete melting, the mixture is combined with zinc, the resulting composition is rolled. Next, cut the rolled sheet with scissors, weigh it on the scales. For productive work, you need: a spoon, sandpaper, a gas burner, scales, folds, a mixing spoon. Silver solders cannot be made without brass, silver, pure zinc, borax. For the manufacture of technical solder, silver 94 or 96 samples is suitable. You can get such metal by burning silver items: galloons, braids, brocades.
Smelting solder
Fusing the metals that are part of the mixture, silver solder for steel is obtained in the crucible. The gel is placed in the forge, having prepared special equipment: a borax, a container with water, a coal mixture, an iron hook, a crucible. First, refractory metals must be melted, and then fusible metals are added 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, there arefine-grained solder drops. They are dried, then re-melted, covered with borax. Once the metal is completely melted, it is poured into special molds. After hardening, the bars or tiles are rolled into thin strips. For subsequent use, they are cut on a lathe into a thin wire.
Characteristics of medium melting compositions
What are homemade silver solders? Their properties are similar to those compositions that are obtained in 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 surfaces to be soldered, gives an even and durable seam. If you need to make an alloy of the PSP-72 brand, it is important to remember that when alloyed with lithium, the melting point with copper decreases. This composition is suitable for brazing steel parts resistant to chemical corrosion.
Preparation of solder at home: features and algorithm
Soldering with silver solder at home also involves the reverse process - the transformation of liquid metal into a solid state. First, it is important to completely melt the silver, then it is cast into the Ingus. All work is divided into three stages: making a spoon - smelter, adding flux, placing a charge in a spoon, melting the source material, placing it in the Ingus.
Place a small cardboard rectangle at the bottom of the spoon, then a slightly larger plate so that itwrapped around the edge of the spoon. Then sheets of cardboard are fried with high quality. The bed must be concave to achieve the desired result. The process of melting solder at home is lengthy, so you have to be patient. Sorting of the charge is carried out on jewelry scales. The crafter will need the following materials:
- jewelry electronic scales;
- 20g 916 sterling silver scrap;
- 875 silver scrap;
- sterling silver (12 grams);
- borax;
- solder metal;
- gas burner
The whole mixture is divided into several piles of 18-20 grams. Silver and scrap of 875 samples are mixed. For one heat, approximately 6 grams of scrap and 42% pure metal will be required. It is cleaned of iron impurities with a magnet.
For the manufacture of solder, 875 silver and copper are taken, the ratio should be 4 to 1 (a silver fifty and three copper coins will be required). For the flux, a drill is used in a ratio of 1 to 10. Next, the flame is adjusted. Too high a fire is not recommended, this will lead to the combustion of metals, and not their melting. A spoon is placed over the gas burner. In the process of melting, the color of silver changes, it flows to the bottom.
Next, the Ingus is placed near the flame to warm it up. For high-quality melting, it is first lubricated with wax. Do not allow the melt to cool and shine, this will adversely affect the technical characteristics of the solder. Liquid metal is slowly poured into a heated ingus. Then cold water is released. After the bar has completely cooled, pull it out, turning it over forthis form. Asbestos or cardboard cover can be used for 3-5 heats.
Silver repair
Beautiful chains, bracelets, earrings, forks, spoons, silver coasters decorate a person's life. But over time, precious metal products break down and need to be repaired or restored. To perform such work, you will need silver solder. For 925 samples, you can make it yourself, using the advice of professional jewelers. The following materials and tools are required for work: regular and irregular soldering irons, solder casting, silver scrap. The easiest way to repair a broken chain is to take it to a jeweler. But if you wish, you can cope with the problem at home, saving money. To solder silver on your own, you need to master the algorithm of actions, technological methods, and study the physical characteristics of silver and its alloys.
Rules for soldering silver items
To perform such actions, it is important to have information about the physical and chemical characteristics of the material. The melting point of silver is 960 degrees Celsius. From the point of view of jewelers, this is an average figure. For example, copper melts at 1083ºС, gold melts at 1063ºС.
Depending on the components that make up the silver, their temperature will change. In order to accurately find out the characteristics of the alloy, you can use technical manuals. Silver markingsolders implies a sequence of Russian letters and numbers. The numbers characterize the percentage of noble metal in the solder.
To repair a silver product, you need to prepare a soldering iron, clean the surface of the product. Silver solder allows you to make strong, tight seams that are resistant to corrosion. When repairing jewelry, solder is used containing more than 70 percent silver, or a special soldering paste.
At home, alloys of silver, zinc, copper, cadmium are suitable for repairing small jewelry. The following composition will be optimal for "beginners": 45 parts of silver, 25 - copper, 30 - zinc. The melting of the components is carried out in a muffle furnace, a flux is required. The finished mixture is poured onto a substrate, after cooling, it is passed through a rolling machine to obtain thin sheets. Their thickness should not exceed 0.5 mm. For home soldering, sheets are needed, the width of which is 1-3 mm. For home soldering of silver jewelry, it is undesirable to use compositions containing cadmium. This metal causes serious he alth problems. The soldering point is exposed to air, oxides are formed. To prevent this phenomenon, colophony (flux) is used in home soldering. When melting silver solder, it is important to monitor the uniform distribution of the flux over the surface to be treated. 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 compounds containing cadmium at home, as evaporationit negatively affects he alth. Flux (colophonium) can be used to prevent the oxidative process and other negative reactions. It is important that it is evenly distributed over the surface of the metal.
Conclusion
Silver soldering will require special skills and courage from the master. The desired result is possible only if the flux, silver solder is correctly selected. Scrap silver is not suitable for home repairs, since the melting point will be lower than that of the restored product. Not suitable for work and compositions that have an equal melting index with pure silver. This will cause the solder to leak during melting.
