Akira Koiso is responsible for the manufacture of electronic circuit boards that are used in industrial equipment such as coordinate measuring machines and IC steppers and scanners. He solders numerous electronic components, such as integrated circuits (ICs), resistors, and condensers, to printed-circuit boards (PCBs), in order to finish the electronic circuit boards.

The production of electronic circuit boards consists of both automated processes and a manual soldering process.

In the automated soldering process, solder paste is smeared on the PCB, an auto-mounter mounts the electronic components on the PCB, and then the PCB is heated and cooled in a reflow furnace. In the manual soldering process that follows, components that cannot be mounted using an automated process are mounted by hand. Mr. Koiso is responsible for supervision of the automated processes as well as for the manual soldering process.

Due to improved miniaturization and heat-resistance, it is now possible to solder many electronic components using an automated process. However, there are electronic components that are not amenable to automated processes by reason of their size or shape. Manual soldering also represents the only means for replacing electronic components on an already completed electronic circuit board. Thus, manual soldering still remains an indispensable technique.

• The ideal: forming a proper fillet
• One second is too short—two seconds is too long
• The manual soldering process
• Lingering questions