Combination of vacuum and positive pressure in motor stator potting process

A method of manufacturing a potted stator assembly, comprising:

• inserting a stator assembly into a vacuum chamber, the stator assembly comprising a housing having a cavity formed therein and a stator located within the cavity, the stator assembly containing an integral cooling tube located radially inward of the stator;
• the cooling tube is separated from the stator by a gap, wherein the gap is non-uniform at all points around a circumference of the cooling tube, and wherein the gap has wider-gap areas that are alternated with narrower-gap areas, applying a vacuum to the stator assembly in the vacuum chamber;
• flowing a potting material into a gap between the stator and the cooling tube, the gap extending a first distance longitudinally between the stator and the cooling tube;
• and applying a pressure to the potting material to push the potting material further into the gap;
• and applying the pressure to the potting material to push the potting material further into the gap further comprises inserting the housing into a pressure vessel, and applying air pressure to the potting material to push the potting material further into the gap, wherein increased pressure in the pressure vessel as compared with ambient pressure results in the potting material at the ends of the gap in the stator assembly being pushed further into the center, along the longitudinal distance, of the gap, wherein the potting material completely fills the narrower-gap areas.