Runner constrictions

Short shot n. In injection molding, failure to fill all cavities of the mold completely, caused by too low melt temperature, too low injection pressure, insufficient plasti-cation time, too constricted gates, too viscous resin, inadequate venting of cavities, etc. Short shots are often made deliberately when testing a new multicavity mold to reveal the pattern of runner flow and the sequence of cavity filling. 

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