Case Study: Fill VelocityThis was a case with a burn appearing at an end of fill knit line. The burn had the classic appearance of charred material and was leaving a black deposit on the surface of the mold in this area. Slowing the velocity eliminated the burn by giving the gas time to escape the cavity. A mold maker was brought over and he opened the vent to a deeper depth, which allowed the fill velocity to be set at the original value. By opening the vents it was possible to achieve a faster fill time, which saved over 2 seconds of cycle time.