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Printed Circuit Board Sol... When soldering components onto PCBs, various techniques can be applied. These...
Solderable Metal Tin Tin is a chemical element that exists mostly as a silvery metal that does not...
Risks To Watch Out For Wh... Soldering iron kits...

Risks To Watch Out For While Soldering

Soldering iron kits (http://www.amazon.com/iCooker-Soldering-Iron-Watt-Solder/dp/B01774KARE)  make use of electricity, heat and various chemical elements that are toxic to humans. While using a soldering iron, watch out for these potential hazards:

Rosin fumes ingestion. When rosin is heated, it generates a wide range of fumes, most of which cause discomfort, allergies and in situations of high exposure causes respiratory problems. Continued exposure to these fumes causes long-term respiratory problems that are very difficult if not impossible to reverse.

Accidental burns represent a significant health risk while soldering. Burns could result from exposure to the soldering iron tip, electrical malfunction or from the above-mentioned fire hazard. Most soldering iron tips operate at temperatures north of 400 degrees Fahrenheit. If one was to come into contact with the tip at this temperature, then it would almost certainly result to a serious burn.

Electric shock is also a potential hazard where an electric current finds its way to the body of the soldering iron operator, once again probably due to an electric fault. Depending on the current and exposure time, this could be serious or mild. Other toxic metals found in solder include cadmium and antimony, both of which have currently been heavily regulated.

Perhaps the most significant potential risk is that of accidental fires that may arise as a result of electrical failures. Soldering irons contain e heat resistive element through which an electric current is passed. Failure in this or another component of the iron could cause a fire. Fires could also result from any other point within the electrical connection.

Printed Circuit Board Soldering Techniques

When soldering components onto PCBs, various techniques can be applied. These include the surface mount technology, through-hole technology, wave reflow and resistance soldering. To describe each in further detail:

Surface mount technology allows soldering of components directly onto the surface of the PCB without the need to pass leads through the board. Surface-mounted components are becoming more and more common due to the obvious shortcomings associated with the use of through-hole soldering. However, the technique is a bit less straightforward as compared to the through-hole technique.

Through-hole soldering is one of the more popular electronic component mounting schemes used in a wide range of printed circuit boards. The components to be mounted have leads running from both ends. These leads then pass through holes within the circuit boards onto which they are fixed then soldered using any of a wide range of techniques. The most common include manual soldering for small-scale tasks and automated soldering for production lines. There are two main types of leads used in through-hole soldering. These include radial and axial leads.

Wave reflow is a soldering technique used to bind components onto PCBs using the surface-mount technique. Under the method, solder paste is applied to the legs of components to be soldered onto the printed circuit board. The solder paste holds the components in place temporarily. After this, the entire board is passed through a heat source such as infrared waves or a reflow oven. Once exposed to heat, the solder paste melts. Upon cooling, the solder solidifies and thus bonds the components to the surface permanently.

Lastly, wave soldering is one of the traditional techniques used to solder components onto PCBs in large scale. The technique is especially successful with the through-hole technology but requires minor adjustments to function with surface-mounted components

Solderable Metal Tin

Tin is a chemical element that exists mostly as a silvery metal that does not easily oxidize. It’s tensile and shear strength makes it highly suitable for soldering both as an alloy and in its pure form. In soldering, tin-solver-copper is among the most common alloys since the ban on use of lead-based solder. In industrial applications, the tin-silver-copper, often known as SAC alloy is the solder of choice for SMT soldering of elements into PCBs. Under this method, components are placed and soldered directly onto PCBs unlike in other methods such as the through-hole technology where components are passed through openings.

SAC solder has the advantage of being lead free and thus exhibiting none of the shortcoming associated with lead poisoning while still maintaining virtually all advantages of lead-based solder. Tin is found naturally in cassiterite which happens to be tin’s main ore. The largest reserves of the metal are in china and other Asian countries such as Indonesia and Malaysia. The soldering process involving tin and tin-based alloys is pretty straightforward and involves cleaning, flux application, preheating, and solder application, flow, cooling, cleaning and testing.

However, despite all its qualities, it’s usually not advisable to use tin in its pure form as solder due to the relatively weak joints it forms. As much as the tensile and shear strength qualities of tin are excellent, in its pure state, soldered joints are relatively weak as compared to those of other metals and of tin alloys. This is primarily the reason why its almost always used as a zinc alloy or a copper alloy. Tin in itself has a melting point of about 450 degrees Fahrenheit and a much lower liquidus.