In everyday life , brass products are often found . When repairing them, owners have to resort to soldering technology. Since this method of joining metals has specific features, beginners may experience difficulties during work. Therefore, they are interested in how to solder brass. If you know the technology and follow the recommendations of specialists, everyone can handle this procedure. Information on how to solder brass at home, you will find in this article.
About the composition of alloys
In everyday life, there are many different parts containing brass and bronze. Despite the external similarity of these copper alloys, they have different compositions. Brass is a copper-zinc alloy to which tin, aluminum and other metals are added during production. Bronze is a combination of tin, aluminum, lead and other substances with copper. The composition of brass with the addition of tin is close to bronze, but zinc predominates at the base of the metal.
What are the features of using copper alloys
Many beginners ask how to solder bronze and brass. Interest is due to the fact that soldering is associated with some difficulties. During thermal exposure, active evaporation from zinc alloy occurs, resulting in the formation of a dense film of zinc and copper oxides. Destroy it quite difficult. According to experts, rosin will not cope with this task.
The master will have to use special fluxes. If tin-lead solder is used, there is a risk that the joint will be of low mechanical strength. In contrast to copper soldering, in this case, the strength index will be one and a half times lower. The reason is volatile zinc. The choice of the method of soldering bronze parts will depend on its composition. High tin and nickel bronzes should be soldered using tin-lead solders. It is better to combine bronze containing aluminum and beryllium with special solders and fluxes.
About fluxes
Their task is to remove the formed film from the surface of the metals being joined and to prevent its further appearance. According to expert reviews, rosin is suitable for soldering copper products. The situation is different with brass. How to solder this alloy? Which flux to choose? Such questions are very often asked by beginners. Experienced craftsmen advise using a more “aggressive” flux than rosin. Since metals are used as additives in brass production, fluxes with different compositions should be used for soldering. To work with the most common brands of brass L63 and LS59, a flux containing zinc chloride and boric acid is intended. For LKS80 with lead and silicon, the best option is a borax-based flux containing boron, potassium and fluorine. On the shelves of specialized stores there are already ready-made trains. Experts recommend paying attention to the fluxes PV-209, PV-209X and "Borax". Anyone who wants to save money can prepare a flux at home.
About Handicraft Flux
According to numerous consumer reviews, this composition can work with different brands of brass. Preparing a flux is not very difficult. You need to take 20 g of borax powder and mix with boric acid, which will also require no more than 20 g. The dry composition of the substance is thoroughly mixed. Then the mixture must be filled with water (200 ml). Before use, the mixture should be boiled and cooled.
About solder
Using this molten metal, brazing is carried out. In a liquid state, it penetrates into the brazed metals, and then cools down, as a result of which the connection occurs. The melting point of the solder must necessarily be lower than the melting temperature of the metals themselves. For those who are interested in whether it is possible to solder brass with tin, experienced craftsmen recommend using solder with good adhesion. Conventional tin and lead alloys are best used in cases where high mechanical strength is not required. Also, solder is suitable when the appearance of the junction is not important.
About the compositions of solders
The choice of solder depends on the brand of brass. Silver alloys 12-72, brass 36-54 and copper-phosphorus are recommended for brass with a predominance of copper in its composition. If there is more zinc in the metal, then you need to work with silver solders from PSr40 no lower. Unstable phosphorus compounds of zinc are formed with phosphorous compounds, which reduces the mechanical strength of adhesions. For parts that are not subjected to shock and vibration during operation, MPC brass solders are suitable. Note that brass can easily dissolve, so craftsmen, using silver and phosphorous solders, should reduce the heating and soldering times.
To work with stationary parts (radiators and pipes), experienced craftsmen recommend using special solders with complex compositions. According to numerous consumer reviews, L-CuP6, which melts at a temperature of 730 degrees, is very popular. You can prepare solder at home.
How to do it
For brazing, it is best to use silver solder. It is desirable that the melting point was a special crucible adapted for significant thermal effects. As a material for crucibles, contact coal elements for a trolley bus can be used. When heated, they do not represent value, and a home craftsman can adapt them for the manufacture of solder. A recess of 20 x 20 mm should be made in this product. Next, a groove should be made to it. It will be easier to remove the solder if its width is 0.5 cm.
Solder is made of silver and copper (2: 1). After taking the right amount of metals, they should be placed in a crucible. Their heat treatment is carried out by a gas burner. Some craftsmen consumables are pre-crumbled. In this case, the melting procedure is much simpler. Next, a steel or ceramic (porcelain) rod is added to the composition. Brass can be soldered when the solder of artisanal manufacture completely hardens.
How to perform a gas burner soldering
How to solder brass? The procedure is as follows:
- Before starting the process, you need to heat the metals. This work is being carried out on heat-resistant materials. Experts advise using an asbestos plate.
- Soldered parts must be combined with each other.
- Wipe surfaces thoroughly with a flux.
- Cut silver solder. Ultimately, it should be a chip that should be poured at the junction of metals.
- Adjust the flame in the gas burner. To seize the solder with the surfaces of metals, the joint is first heated by low heat.
- Set the gas burner to 750 degrees for the main heating. A red tint should form on the brass surface. All gaps are filled with solder, then it spreads throughout the junction.
- Turn off the burner and allow the product to cool. The procedure is considered performed correctly if a seam is obtained that differs little from metal.
- Rinse junction to remove residual flux.
How to solder brass with a soldering iron
This method is the most common, because it is easiest to perform. Those who do not know how to solder brass with a soldering iron at home, experts recommend that you follow the following algorithm of actions:
- At the very beginning, you need to clean the parts to be connected. On metal surfaces there should be no various extraneous layers and pollution.
- Place parts on a special refractory stand. You can make it at home from improvised means.
- To remove all defects in the brass surface, treat the junction with a flux.
- Sprinkle crumb solder on top.
- Perform warming up with a soldering iron.
Very often, newcomers ask how to solder brass and copper with brass. Specialists recommend the use of low-temperature soldering, which is able to provide high-quality connection. For this purpose, a soldering iron, the power of which is not more than 100 W, and phosphoric acid will be required. Before work, the surface of the product is thoroughly degreased, the oxide film is removed from it. It is better to connect metals with the help of tin-lead solder POS60. To begin to solder brass, the tool should be well heated.
To work with silver solders you will need a soldering iron, the power of which varies from 0.5 to 1 kW. Degreasing is carried out by flux - concentrated phosphoric acid. Borax based flux is also considered quite effective. In the soldering zone, a temperature of at least 500 degrees is formed.
Stainless steel works
According to numerous reviews, home craftsmen often have to braze stainless steel. Since the presence of nickel and chromium in the compositions of steel alloys does not exceed 25%, working with such materials is less time-consuming. In addition, this composition provides a reliable connection of stainless steel parts with other metals.
The exception is magnesium and aluminum. If stainless steel with a significant nickel content, then as a result of its heating to 700 degrees, carbide compounds are formed. The longer the heating, the more intense they are formed. For this reason, soldering should be done as quickly as possible. The risk of formation of these compounds will be minimal if titanium is added to the alloy during brazing. According to experienced craftsmen, you should especially be careful with riveted stainless steel. This is due to the fact that cracks may appear on the metal surface. To prevent their formation, soldering is performed after preliminary annealing of the parts.
Working process
Stainless steel soldering is performed as follows:
- First, the surface is thoroughly cleaned with sandpaper or a file.
- Further, the place of adhesion is treated with flux, namely soldering acid.
- Then the surface needs to be tinned - apply a thin layer of solder containing tin and lead to them. It happens that it is not possible to apply solder the first time. In this case, you will have to apply a brush containing metal cores. They will be much more comfortable to remove the oxide film that prevents tinning.
- Using a soldering iron and solder, solder parts.
Finally
The soldering process only at first glance may seem complicated. There will be no problems if you master the technology and work with correctly selected consumables.