The parting line is the portion of the mold where the “A” and “B” (and “X” when appropriate) separate during the mold open sequence. It is the split surface of the mold.
Typically referred to as the “center” of the mold, the parting line is often not the center of the mold but normally offset towards the “A” plate. It is the plane which crosses the length and width of the mold. It is where the mold separates.
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