Introduction about SMD, surface-mount technology micro soldering. With the advancement of the technology, and the commercialization of the devices, increasingly smaller, and increasingly
expensive, in cases of breakdowns, many times, repair them, is more beneficial, than change them for other new devices. The micro soldering of precision, represents the act of soldering so small components, that only can be observe through a microscope. For example a generic tablet that costs almost 70 euros
generally in cases of breakdowns isn't worth the time invested, in find the solution to the fault. These small components are usually inductor, capacitor, resistors, FPC connectors integrated circuits coils and
so on. Any component, that needs to be repaired, and soldering with the help of a microscope, would be considered, micro-soldering. All of them fit into a motherboard
formed by multiple layers embedded in small spaces and together with the macro
components constitute the mobile devices tablets and even laptops.

Usually a soldering ,by resistance is considered micro soldering, in case if it has 0.05 diameter cables, or thin wires, less than 0 04 inches of thickness, which can be welded, with less than 500 amperes of current. This is a heating system exclusive JBC, that can reach up to 350 degrees, in just two seconds. For a micro professional soldering we need professional tools, because using them, the user can work with lower temperatures, and in this way we can get greater efficiency at work. JBC contains more than 400 cartridges, with different forms, and measures, adapted to our needs, that ensure an efficient control over the temperature. Tip extractors allows, change the cartridges quickly and sure, and that saves time, and increase productivity. The JBC station, is designed, to adapt at the worker's work position, and is the best solution, for a successful manual soldering. Large companies use it, like: FOXCONN, Apple, Huawei, Boeing, BQ, Siemens, Motorola, Intel and Google.

The lenses of the microscope.The objective, is the revolver, enlarges the image, and is a vital element, that allows you, to see through of the eyepieces. The eyepiece is
the lens located near the eye of the observer.If we change the eyepieces, of 10 increases, for others of 20 increases, we can further expand the image formed,between the two objectives. For example let's observe the motherboard of an
iPhone device and later we will observe it with the help of a 180 x increases.
Now imagine trying to place a small drop of solder in one of those little
components. It's almost impossible without a good microscope without an
soldering iron with a very thin pencil tip. Without, using a microscope, it's practically impossible, to perform soldering, of the tracks, of a SIM card reader. In this image, you can see the correctly working distance, for each objective. For a 0.5X objective, we have a little more, than 20 centimeters, away to work. Now we are going to check it. We use as an example, a needle syringe, to show the size of a SMD, surface-mount-technology component. Placing a 1X objective, we will have less working distance, but a lot more increases, and more clarity in glasses.

Let's check the distance of work, with a 1X objective. We increase now, up to 90X. Comparative with the needle, the S M D components are very small. They are appropriate, for soldering and repairing very small-sized components, at high precision, even under a microscope. We use fiber optic light, to provide bright, and fresh lighting. When the components, and "integrated circuits" , has a smaller size, many times we will need a tip weld, very small , with 0.01 of diameter. Surface-mount device components. On the motherboard, of a mobile device,or a tablet, we have a crowd of surface-mount device, components. What is an surface-mount device component? Not long ago,these components, they welded themselves, by inserting their paws in the holes in the motherboard.Now on day, on the motherboard, there are no holes, there are only copper squares, where the surface-mount device components, are welded. It is the surface
mount technology or on the surface. An SMD component, is a electronic component, that as a rule general, is soldering directly, into the surface of the motherboard. These components, are not different, regarding the electrical function, however, they are much smaller, and they provide better electric performance.

Types of soldering: There are many types of micro soldering, according to the work, you need to perform, for example: lead soldering, and without lead. Soldering mixture more common that exists in the market. The selection
of the alloy is determined by the job we need to perform the melting temperature
and by the physical properties of each chemical element. Soldering would lead
has the lower melting temperature about 183 Celsius degrees. Usually we are going to work with the fusing temperature between 180 Celsius degrees and 240
degrees. We can also, have other alloys, welds available. Below, I ll attach an image, with the tin melting scale. There are, the following welding alloys: from high temperature, medium range, low temperature, and without lead. We know, that the lead melting temperature, is 327 degrees and the melting temperature of
tin, is 231. So to lower this temperature, it has had to make an mixture, of these two chemical elements.

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