The individual needles of a glass feeder mechanism which control the volume of the streams of molten glass sheared into discrete gobs are displaceable to adjust the size of the sheared gobs. The controller for the motor, which raises or lowers a stream, receives positional data from the plunger, which forms the gob into a parison, and determines the Parison Formation Point for that parison and raises or lowers the needle to maintain that point at a desired plunger location.