Sink mark happened due to low holding pressure. To solve Sink mark, increased holding pressure, but mold flash happened.② Multiple holding pressureThe first holding pressure is low to make thin skin layer.The second holding pressure is high to minimize Sink mark.No mold flash!(2)Changeover time is too longIf TP1 setting is long, the skin layer solidified completely and the gate also solidified.If TP1 setting is short, before making thin skin layer, higher holding pressure applies to the cavity and mold flash happens.