It is safe to assume that the majority of the population does not have much in the way of soldering experience, so when a problem should arise with a printed circuit board, sending it in for repair or buying a completely new component might seem to be the only option. Luckily, there are a few techniques that anyone with minimal soldering experience can do to fix their PCB. Before beginning any soldering project, it is important to know what tools to use and why. Here are some of the basics that go in to soldering:
There are numerous amounts of soldering tools on the market that range in price from simple soldering irons to soldering guns and stations. Soldering irons on the cheaper side of the spectrum will do most simple soldering jobs. However, these typically are not manufactured with the ability to alter the temperature therefore posing the risk of inflicting damage to a PCB. At AER Technologies Inc, our technicians are equipped with a soldering and desoldering station. This soldering unit allows temperatures to be maintained and has a cleaning site attached.
Soldering Iron Tips
In addition to the numerous amounts of soldering tools available, there are even more soldering iron tips. The tip chosen should be determined by the electrical components the technician will be working on. Smaller tips are used for precise pin point jobs and transfer less heat whereas larger tips easily transfer heat and are faster to work with. In explaining the difference in soldering tips used, one of AER Technologies Inc. technicians with over 25 years of experience in electronic rework favors an angled tip when soldering in the corner of a unit as it allows easy access to the connection joint as opposed to other tips.
Choosing the type of solder used is also determined by the type of soldering job needed. Some types of solder include wire, pellets, bars, and paste. The most common type of solder used is a mixture of lead and tin with a flux core. While there is fear in the damaging effects of using lead, there is actually a minimal amount of lead used and shouldn’t pose a threat when heating. Lead free solder is available; unfortunately, it is not as easy to work with and requires more heat. Once soldered, it takes on a dull appearance which can make determining whether a soldering joint is oxidized difficult. Lead/ tin solder takes on a shinny appearance once heated, making it easier to spot oxidation. For jobs that require lead free solder, AER Technologies Inc. has designated lead free stations to avoid contamination.
The most common type of flux used in electronic rework is rosin based flux. When working with rosin flux, a residue will be left behind. It is imperative that the flux is cleaned off of the unit to avoid long term problems such as corrosion. The left over flux can be cleaned off using a brush and isopropyl alcohol. Another type is no-clean flux, which was designed to not leave behind residue, and any residue that may be left behind will not cause any long term damage. Finally, there is acid based flux which should never be used on electrical components as it is used for plumbing and can eat away at electrical components.
In conclusion, all tools should be chosen based on the type of product in need of repair. If you are still unsure exactly what to use, it would be beneficial to do some research or ask a soldering technician to avoid damaging your PCB.