Every amateur or repairman who works on his own will sooner or later have to pick up a soldering iron and try it. The quality of the work performed and even the performance of the product will directly depend on many factors, which you must know about before starting work.
Correct work with a soldering iron
Despite the apparent simplicity of working with a soldering iron, it is very desirable to have the initial skills of high-quality work and be able to correctly use solder with rosin.
Soldering is done using a variety of solders. The so-called solder in a coil with rosin is perhaps the most popular. When performing work related to soldering, solder is used. The amount of tin and lead contained in it is 60 and 40%, respectively. This alloy melts at 180 gr.
What is necessary for working with a soldering iron:
- soldering iron itself;
- solder;
- rosin.
Heated solder creates sufficient internal connection with metals such as copper, brass, silver, etc., if the following conditions are met:
- The surfaces of the parts must be cleaned from oxides.
- The part at the place of soldering is heated more strongly than the melting point of the solder itself.
- During operation, the soldering place needs to be protected from oxygen, various fluxes are used for this. They create a protective film directly above the soldering point.
A book on how to solder can be read and understood, but soldering skills can only be gained in practice.
Tricks and secrets of working with a soldering iron
After the solder has started to melt, they can already be soldered. To do this, cover the soldering iron tip with a thick layer of solder, and then wipe it well on a damp sponge. So remove the solder with rosin remaining from work. It will not be superfluous to take in the habit of wiping the sting on a wet sponge every time after soldering.
Before you begin to solder the radio part, you need to prepare it. It is necessary to bend its conclusions so that the part freely entered into the holes intended for it.
Beginners with no work experience often relate to the place of soldering with the tip of a soldering iron tip. And you need to hold the soldering iron so that between it and the place of soldering the contact area is as large as possible, otherwise the place where you need to solder is not heated enough to hold the parts together.
How to clean a soldering iron tip
When soldering, a soot often appears on the soldering iron. It can be removed with plain water. If you hold a soldering iron over a damp cloth, then the scale will remain on it, and the sting will become clean again. Periodically, you need to do this while working with a soldering iron. If the fabric does not help, you can use a stiff sponge.
Soldering Tip Classes
- Removable tips with nickel coating.
- Copper stings.
First-class soldering tips are usually used in complex soldering irons, in which it is possible to regulate the temperature.
The stings of the second are the most common.
Types of nickel plated soldering tips
- Needle-shaped sting - very small radio components such as SMD are soldered to them. When repairing phones, such a sting is indispensable. It is used on boards with a high density of mounted parts.
- Sting-spatula - used for soldering and in cases of installation of large radio components. They work with multi-pin microcircuits.
- The tip is in the form of a drop - it is convenient for them to transfer the solder with rosin to the place of soldering, which leads to an increase in the quality of work.
- A sting with a curved shape - most often they solder the radio parts located in the copper shell so that there is no excess solder on the board. It can also be used for conventional soldering. The soldering iron is heated to a temperature of 290-300 C.
When working with a soldering iron, you must always keep it in perfect cleanliness. New soldering tips are usually machined with a hammer to form small nicks on its surface. Subsequently, they are carefully trimmed with a file to give the sting the most regular shape.
Then the sting should be tinned using solder with rosin. That is, cover with a thin layer of solder by dipping it in rosin.
How to cool the soldering place
Metal tweezers, which hold the radio part, also work as a heat sink during the soldering process. You can use a special crocodile clip for this purpose.
Secrets of soldering with a soldering iron
To obtain a good result when soldering, it is necessary to correctly apply solder with rosin and flux. This is a low-melting alloy of a special metal, which solders the conclusions of parts and wires.
- The best solder is pure tin. But such a metal is too expensive to use when soldering. Therefore, when working with radio components, so-called lead-tin solders are used.
- Lead with tin. In terms of soldering strength, these solders are no worse than pure tin. They melt at a temperature of 170-190 degrees. It is customary to designate such solders with the abbreviation "POS" - tin-lead solder. The number after these letters in the designation means the percentage of tin, expressed as a percentage. It is better to use POS-6O solder.
- Fluxes are substances that have antioxidant properties. They are used to prevent oxidation of the solder. If you do not use flux, then the solder simply does not stick to the surface of the metal.
Types of Fluxes
When working with radio components, fluxes are used that do not contain acid. For example, rosin. Bow rosin for lubricating musical instruments is also sold in stores. It can also be used for soldering. But the metal utensils are soldered using solder without rosin. To repair it, "soldering acid" is required . It is zinc dissolved in hydrochloric acid. It is also impossible to solder the radio parts with such solder, since over time it will destroy the solder.
If you want to solder in hard-to-reach places, you need to have a liquid flux. It can be made independently. Rosin is crushed into powder, poured into acetone or ethyl alcohol. After stirring the solution, you need to add another rosin to obtain a thick mushy mass. At the place of soldering, such a liquid rosin should be applied with a brush or stick. At the same time, there is a nuance - for working with printed circuit boards, the flux must be more liquid. For hard-to-reach spots, you can also use solder wire with rosin, which is much more convenient.
When working with various fluxes, it is necessary to take into account that those that contain acetone are very toxic. Therefore, when working with them, it is necessary to avoid the entry of vapors into the respiratory tract. It is better to solder near the window, if it is summer, and in winter often ventilate the room in which work is carried out. At the end of the work, be sure to wash your hands with soap in warm water.
How to solder solder with rosin
An important condition for successful soldering is the observance of the cleanliness of the surfaces that need to be soldered. Be sure to clean the soldering spots to a shine. Then the details need to be put on a piece of rosin and heated. The molten rosin will help the solder to evenly flow along the conductor or part that needs to be soldered. You can gently rotate the part, while leading along it with a soldering iron tip, so that the solder spreads evenly over the surface.
If you need to tin the conductor, which is soldered into the board, then after stripping the soldering place with sanding paper or a knife, you need to bring a piece of rosin, and then smoothly distribute the solder as evenly as possible, using a soldering iron.
The quality of soldering is also affected by how correctly wires or parts contacts are connected when soldering. They should be pressed tightly together and then bring the soldering iron to the prepared conductors, touching it. After the heated solder spreads over the surface, filling even small gaps between them, the soldering iron should be removed.
The time of continuous soldering should be no more than five seconds. After this period of time, the solder will harden and the parts will be firmly fastened. However, so that the soldering does not collapse, the parts must not be moved within 10-15 seconds after the end of the soldering. Otherwise, the connection will be fragile.
If work is done with transistors, then their conclusions must be protected so as not to overheat. It is better to hold them with either pliers or tweezers, thereby performing heat dissipation.
When soldering radio parts, in no case should you twist the ends of the parts. If you need to solder parts or replace conductors, then you need to think about this in advance, before starting installation. The ends of the parts are best soldered at a small distance from each other, and not in one place.