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 re-torque blanket

Prolonged use of oily wash-up solutions has occurred

Change to fresh wash-up solution

Plate is not properly sensitized

Consult your pre-press department

Fountain solution is out of balance

Drain pans and tanks. Refill with fountain solution of correct pH and conductivity

Ink film is too heavy

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

Roller train temperature is too hot

Maintain 80°-85° F surface temperature on oscillators

Fountain solution is too hot in pans

Maintain fountain solution at 60°-65° F in press pans

Blanket is glazed

Remove glaze or change blanket