Finding top tier soldering talent is becoming more difficult year by year as access to automation increases. We have been very fortunate to have Debi Thompkins with more than 40 years of experience. As our production needs grow, we have found a need for quality soldering on a larger scale than our resident expert can keep up with. That is why we are currently setting up a new selective soldering machine. This machine can apply solder with great accuracy and exact timing to each and every pin location one at a time. This keeps the components and connectors free of the thermal shock found in traditional wave soldering machines. Debi will begin offsetting her hand soldering with our selective solder machine to increase productivity and find better consistency over larger production runs. This will be performed with state of the art inspection and under her experienced eye for the best solder connections.
The process starts with clipping the necessary component leads to length and are assembled into the PCB by hand. The prepared circuit boards are then loaded onto the machine’s waiting tray in an array for maximum throughput. Once started, the machine applies a micro jet of flux to each of the pins for optimized solder flow and finish. Using a variety of nozzles, based on pin size, a solder fountain flows solder onto the selected pins (seen below). We must control the exposure to the solder fountain based on the thermal properties of each pin or connector. Larger pins or pins connected to the ground plane (which can be a heatsink) require extra time to ensure the best connection. Finally, the completed boards are run through our washing machine and inspected with our AOI (Automated Optical Inspection) machine.
