1. Feeder Defective shear blades Worn shear arms Incorrect shear blade tension Defective shear mechanism Worn shear cam - too slow Incorrectly adjusted shear arm - not cutting centrally Inefficient shear spray operation Dirty shear blades - accumulation of carbon or oil Improper gob shape Glass too cold There is not enough or too much shear overlap Shear blades loose Shears cutting too low   1. Feeder Change shear blades Change shear arm gear sectors Correct tension of shear blades Change shear mechanism Change sheer cam Centralize shear arm properly Adjust shear spray heads Reshape the gob Adjust the feeder temperature Adjust for correct overlap Tighten shear blades in the holder Raise the shear mechanism