Scumming

Ink rollers are of the wrong durometer (too soft  or too hard)

Check durometer, setting and condition of ink rollers

Ink or dampener rollers are set too tight

Check and reset rollers

Blanket is overpacked or not tight

Correct packing and retorque blanket

Prolonged use of oily wash-up solutions has occurred

Consult your pre-press department

Fountain solution is out of balance

Adjust pH and conductivity

Dampening system is improperly maintained

Conduct proper maintenance.  Refer to Sun Chemical recommended procedures for cleaning and maintenance of fountain solution tanks and press pans

Emulsification characteristics of the ink formulation are incorrect for fountain solution

Consult a Sun Chemical representative

Fountain solution formulation is not correct for ink formulation

Consult a Sun Chemical representative

Ink film is too heavy

Change to a stronger ink and/or consult a Sun Chemical representative

Blanket is glazed

Remove glaze or change blanket