Introduction
The Smart Wave consists of a main wave which can be agitated by the Front Nozzle Pump (FNP) to create a dynamic part at the entrance of the wave. When the FNP is rotating with a too low main wave setting, a gap can be formed between the solder that is pumped vertical by the FNP action and the solder that is flowing over the front plate of the nozzle back into the solderpot. Via this gap, or gaps, air can be encapsulated in the FNP pump chamber. Due to the strong mixing action of the rotating pump bar this air will attack the solder in the FNP. As a result of that fine black/grey solder oxide powder will be formed. This powder can adhere to the pump bar and so reduce its effectiveness, but it can also be generated to the solder side of the board which is soldered. From this it is clear that we must prevent the air entrapment gaps to be formed. If the main wave setting is at a too high level the activity of the FNP will be suppressed. This can give cause for skipped joints. A good practical setting can be found if the distance between the inside of the finger V-groove and the FNP cover plate is approximately 8 mm.
Setting
The correct setting can be easily controlled. Be sure that there is always a constant flow of solder at the front plate. This flow may have no interruptions or blank parts where you can see the front plate. If interruptions or blank parts are formed either the FNP setting must be lowered or the main wave setting must be increased. To keep the setting towards the boards constant it may be necessary to adjust the conveyor or the solderpot height.