Common PCB Hand Soldering Issues to Avoid

There are several common PCB soldering issues to avoid for new soldering technicians using a traditional soldering iron.

One of the most common soldering issues is the result of not understanding the issue of a heat bridge. The proper heat bridge needs to be accomplished between the component land and the component lead through the soldering iron tip. If too small a tip is utilized then the new soldering technician will have the hot iron tip on the board for too long of a period. This may cause component or board damage. By using an improperly-sized component from the PCB the new technician may try to leverage the component the lead of a through-hole component up and out thereby causing barrel or annular ring damage. By using a properly-sized soldering tip the chances for damage to the component and board will be minimized.

Another common soldering issue is that of remaining flux residue on /near the soldering joint after the soldering process has taken place. Flux is used during the soldering process to provide the cleaning as well as proper wetting function to the solder. If it is not fully or activated the functioning of the board during the soldering process "soils" left behind may reduce the reliability of the circuit board assembly.

A further issue is the lack of understanding of the soldering process w.r.t time and heat. Often in our classrooms, you will hear our instructors recite the mantra "get in get out and don't hang out". This simple thing to remember will limit thermal and mechanical damage to a board, the solder interconnection as well as the component.

Another issue that is part of the common PCB hand soldering issues is that of lack of understanding of the post assembly inspection of printed circuit board assemblies. If a new soldering technician does not know what the end product should look like how can he/she determine that the workmanship that they performed is a "job well done". Students should become familiarized with the standards for not only workmanship (IPC J-STD-001) as well as the end product quality (IPC-A-610).

Another basic set of safeguards with respect to static electricity, that if not followed, may lead to component and circuit damage, is another PCB hand soldering good practices must-have. When soldering assume that all of the components are sensitive to static electricity damage. This means that before even thinking about soldering the operator must be properly grounded, the board needs to be set on the grounded surface and all static-producing items should be out of the area where the soldering is taking place.

BEST Inc. has been reworking, repairing PCBs for over 20 years. Each year clients who design, produce, and repair printed circuit board assemblies come to BEST Inc. for a plethora of soldering tasks-from removal and replacement of devices to repair the physical elements of a PCB-whether the board itself is a flex, a rigid or of rigid-flex construction. These experiences have made the training of thousands of soldering and wire cable harness students "come to life".