1. Feeder Glass is too hot   1. Feeder Adjust gob temperature 2. Machine Setup and Operation Finish equipment is running too hot Neck ring closing too soon on invert Blow head not set correctly Blow head equalizing holes blocked Neck ring pulling to one side Take-out tongs to set properly or not in line Machine speed too high Insufficient cooling of mold equipment Badly cushioned invert action Take-out action too fast and badly cushioned Missing neckring holder springs Check for missing NR holder springs   2. Machine Setup and Operation Use finish cooling nozzle Adjust neck ring closing Adjust blow head setting Change blow heads Change neck ring and when possible check the neck ring mechanism setting Adjust take-out tong setting over mold Reduce the machine speed Increase the cooling wind to the molds Cushion invert action Slow down take-out operation   3. Mold Equipment Blow mold neck diameter too large so that the parison cannot settle properly in blow mold Blow mold neck diameter too small, causing the parison to be held up and allowing distortion by the blow head Blow head too deep Neck ring incorrectly manufactured - finish and outside dimensions not concentric   3. Mold Equipment Check dimension in accordance with mold design Depth of blow head to be in accordance with mold design book Ensure finish dimensions are concentric with outside dimension