Oce Arizona T220 User Manual - Maintaining Print Quality
Maintaining Print Quality |
10/16/03
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3.5
Maintaining Print Quality
This section includes descriptions of some print quality problems and possible solutions.
It discusses the Diagnostic Stripe, which is a very useful tool for evaluating print
problems — See “Evaluating the Diagnostic Stripe” on page 41. Also, flushing the heads
is often an effective solution to print quality problems — See “Flushing the Heads” on
page 73.
3.5.1
Gradual Degradation in Print Quality
After extended use, print quality may start to suffer – especially after continuously
running at high heat settings. If this happens we recommend that you flush the print
heads with solvent and leave them to soak for at least one hour, but preferably overnight.
Refer to Flushing the Heads for this procedure.
3.5.2
Start of Day (Post-Maintenance)
Head not firing — check that the foam capping pads are positioned correctly. Replace
the pad that is under the affected head and soak the new one with solvent. Initiate a
Recovery Purge and then a Spit for the color of the print head that is not firing. If the
head is still plugged, clean them with swabs (See “Swabbing Printheads” on page 81). If
still plugges after swabbing, syringe and soak the head for at least 5 minutes. Ensure that
all nozzles are clear by observing the curtain of solvent exiting the head.
Poor print quality, multiple nozzle drop out — move carriage to access position,
initiate Operator/Maintenance/Pump Solvent command and verify that solvent flows
along all the channels in the capping tray to suitably soak all of the foam pads. If there
is air in the solvent lines, pump more solvent until it reaches all of the foam pads. Initiate
a recovery purge and, if necessary, syringe the affected print heads and check the curtain
of solvent exiting the heads.
3.5.3
Printing with High Heat
When printing with high heat levels, the ink is more susceptible to drying on the nozzle
plate and causing nozzle dropout and overspray. Swabbing the printheads more
frequently will help prevent this.
If large areas of a print do not require any ink from one or more of the colors then those
nozzles may start to dry out. The 2
nd
Prefire Stripe should be used to help keep those
heads running — See “The Pre-Fire Stripe” on page 45.
3.5.4
Ineffective Drying
If the drying appears to be less effective than usual, the following should be considered:
•
If the printer has been idle for more than an hour then a long purge should
be performed to ensure any solvent that has migrated into the heads has
been expelled.