In everyday life, brass products are often found. When repairing them, the owners have to resort to soldering technology. Since this method of joining metals has specific features, beginners may experience difficulties in the course of 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. You will find information on how to solder brass at home in this article.
About alloy composition
In everyday life there are many different parts containing brass and bronze. Despite the outward 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 in the base of the metal.
What are the features of using copper alloys
Many beginners ask the question of 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 the zinc alloy occurs, resulting in the formation of a dense film of zinc and copper oxides. It's pretty hard to destroy it. According to experts, rosin will not cope with this task either.
The master will have to use special fluxes. If tin-lead solder is used, there is a risk that the joint will have low mechanical strength. Unlike copper soldering, in this case, the strength indicator will be one and a half times lower. The reason for this is evaporating zinc. The choice of method for soldering bronze parts will depend on its composition. Bronze with a high content of tin and nickel should be soldered using tin-lead solders. Bronze containing aluminum and beryllium is best joined with special solders and fluxes.
About fluxes
Their task is to remove the resulting film from the surface of the joined metals and prevent its further appearance. According to experts, rosin is suitable for soldering copper products. The situation is different with brass. How to solder this alloy? What flux to choose? These questions are often asked by beginners. Experienced craftsmen advise using a more "aggressive" flux than rosin. Since metals are used as additives in the production of brass, fluxes with different compositions should be taken for soldering. Flux is designed to work with the most common brands of brass L63 and LS59,containing zinc chloride and boric acid. For LKS80 with lead and silicon, the best option would be a borax-based flux containing boron, potassium and fluorine. On the shelves of specialized stores there are ready-made compositions. Experts recommend paying attention to fluxes PV-209, PV-209X and Bura. If you want to save money, you can make flux at home.
About artisanal flux
According to numerous consumer reviews, this composition can work with different brands of brass. Cooking a flux is not very difficult. It is necessary 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
This molten metal is soldered. In a liquid state, it penetrates into the soldered 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 point 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 alloys containing tin and lead are best used in cases where high mechanical strength is not required. Also, solder is suitable when the appearance of the joint is not important.
About solder formulations
The choice of solder depends on the brand of brass. Silver soldersPSR12-PSr72, brass PMTs36-PMTs54 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 not lower. With phosphorus compounds, unstable phosphorus zinc compounds are formed, which reduces the mechanical strength of the solder joint. For parts that are not subjected to shock and vibration during their operation, MOC brass solders are suitable. Note that brass can dissolve easily, so crafters using silver and phosphorous solders should shorten the heating and soldering time.
To work with permanently fixed parts (radiators and pipes), experienced craftsmen recommend using special hard solders with complex compositions. According to numerous consumer reviews, L-CuP6, which melts at a temperature of 730 degrees, is very popular. You can also prepare solder at home.
How to do it
For soldering brass, it is best to use silver solder. It is desirable that the place of melting be a special crucible adapted for significant thermal effects. As a material for crucibles, contact carbon elements for a trolleybus can be used. In a heated state, they are of no value, and a home craftsman can adapt them for making solder. In this product, a recess of 20 x 20 mm should be made. 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 from silver and copper (2:1). After taking the required amount of metals, they should be placed in a crucible. Their heat treatment is carried out by a gas burner. Some craftsmen pre-crush consumables. In this case, the melting procedure is much simpler. Next, a steel or ceramic (porcelain) rod is added to the composition. You can solder brass when the homemade solder has completely hardened.
How to solder with a gas burner
How to solder brass? The procedure is as follows:
- Before starting the process, you need to heat up the metals. This work is carried out on heat-resistant materials. Experts advise using an asbestos plate.
- The parts to be soldered must be aligned with each other.
- The surfaces at the place of soldering should be thoroughly wiped with flux.
- Cut the silver solder. Ultimately, it should be a shaving that should be poured into the junction of the metals.
- Adjust the flame in the gas burner. To set the solder to metal surfaces, the junction is first warmed up with a weak fire.
- Set the gas burner to 750 degrees for the main heating. A red tint should form on the brass surface. Solder fills all the gaps, then it spreads over the entire junction.
- Turn off the burner and let the product cool down. The procedure is considered performed correctly if a seam is obtained that differs little from metal.
- Rinse the joint to remove residuesflux.
How to solder brass with a soldering iron
This method is the most common because it is the easiest to perform. For those who do not know how to solder brass with a soldering iron at home, experts recommend adhering to the following algorithm of actions:
- At the very beginning, you need to clean the parts to be joined. Metal surfaces must be free of various foreign deposits and contamination.
- Place the parts on a special refractory stand. You can make it at home from improvised means.
- To remove all defects in the brass surface, process the joint with flux.
- Sprinkle crumbs of solder on top.
- Perform warm-up with a soldering iron.
Very often beginners ask the question how to braze copper with brass. Experts advise using low-temperature soldering, which is able to provide a high-quality connection. For this purpose, you will need a soldering iron, the power of which is not more than 100 W, and phosphoric acid. Before work, the surface of the product is thoroughly degreased, the oxide film is removed from it. It is better to join metals using POS60 tin-lead solder. To start soldering brass, the tool should be warmed up well.
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. A flux based onBoers. A temperature of at least 500 degrees is formed in the soldering zone.
Stainless steel work
According to numerous reviews, home craftsmen often have to solder stainless steel with brass. Since the presence of nickel and chromium in the compositions of steel alloys does not exceed 25%, working with such materials is less laborious. In addition, this composition provides a reliable connection of stainless steel parts with other metals.
The exceptions are magnesium and aluminum. If a stainless steel with a significant nickel content, then as a result of its heating to 700 degrees, the formation of carbide compounds occurs. 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 soldering. According to experienced craftsmen, you should be especially careful with riveted stainless steel. This is due to the fact that cracks may appear on the surface of the metal. To prevent their formation, soldering is performed after preliminary annealing of the parts.
Progress of work
Soldering of stainless steel is performed as follows:
- First, the surface is carefully cleaned with sandpaper or a file.
- Next, the soldering point is treated with flux, namely soldering acid.
- Then the surfaces need to be tinned - apply a thin layer of solder containing tin and lead on them. It happens,that it is not possible to apply solder the first time. In this case, you will have to use a brush containing metal veins. They will be much more convenient to remove the oxide film that prevents tinning.
- Using a soldering iron and solder, solder parts.
In conclusion
The soldering process may seem complicated only at first glance. There will be no problems if you master the technology and work with well-chosen consumables.
