ColorSpan Legacy DisplayMaker Solvent - Headstrikes on Solvent Printers

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Other Lingering Effects
Intermittent Jets
These jets may pass an AutoJet or AutoSet calibration, but when printing begins they drop out. The jets have some
small solid particle lodged within the jetting nozzle or orifi ce. As the particle moves around, it can alternately allow
the jet to fi re or it can block the jet completely. Printing a Manual Jet Mapping page immediately after canceling a
print job will often reveal the intermittent jet as missing or as producing a wavy line in the Manual Jet Mapping pat-
tern, as shown below at jets 62 and 77.
Jets showing this phenomenon are usually unrecoverable. Because AutoJet may continue to fi nd them as usable,
the best option is to use Manual Jet Mapping to identify them as “Hard” jet outs, so that AutoJet will not no longer
attempt to evaluate them and mark them as good. Once manually mapped out as “hard”, the jets will remain on the
bad jet list until such time that an operator deliberately clears the Hard Jet-Out list.
“Late” Jets
These jets appear to fi re late (or early, depending on the direction of the carriage). Headstrikes or other damage,
such as improper cleaning of the printhead, have created small scratches on the orifi ce plate around the jets. Small
amounts of ink accumulate within the scratches (held in place by surface tension) and create a fi lm of ink that must
be penetrated by new ink droplets when the jet fi res. The required effort to penetrate through this fi lm is enough to
delay the drop, creating the characteristic parabola shape in one area of the Prime Bars pattern for that head.