1. Feeder Glass too cold Uneven gob temperature   1. Feeder Adjust the temperature of the glass Balance the temperature of forehearth so gob does not curl   2. Machine Setup and Operation Machine speed too low Blanks running too cold Incorrect blank cycle Excessive cooling wind on mold Excessive final blow pressure Excessive plunger cooling (press and blow) Counter blow incorrect Dirty mold equipment Blow head not seating properly Blow head vents stopped up Excessive settle blow Plunger contact time too long   2. Machine Setup and Operation Increase the machine speed Reduce cooling air on blank Adjust blank cycle Reduce cooling wind on mold Reduce final blow pressure Reduce the plunger cooling (press and blow) Correct counterblow time and pressure Change the mold equipment Readjust the blow head seating Change the blow head Reduce the settle blow time Reduce plunger contact time   3. Mold Equipment Incorrect mold design - molds too heavy Insufficient venting of mold Incorrect venting of blow head   3. Mold Equipment Correct mold design - reduce mold weight Increase venting of mold Check venting of blow head