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Solder Short
Solder shorts are becoming a major problem in wave soldering particularly as component pitches continue to decrease. In the example shown shorts are seen on a Pin Grid Array device. Due to the close proximity and the number of pins the solder separation is impeded from the base of the board. Shorting can occur due to poor fluxing, incorrect pre heat or wave separation. All shorting can be decreased through good design rules with reductions in pad size and component lead length. In the case of the example shown it was necessary to change the solids content of the flux but still retaining a no clean process. Using a hot air knife failed to improve the process due to the high mix of boards and pin lengths.