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Common banding causes – Kodak NOVAJET 700 User Manual

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Maintenance

NovaJet 500/630/700 Series Service Manual

If the test file prints correctly, the problem lies in either the software

package that generated the print or the RIP, if used.

A simple test to determine if the banding is caused by the computer/

RIP/application or the printer is to rotate the image 90 degrees and see

if the banding rotates or remains in the same orientation as the previ-

ous print. If the banding does not rotate, then look for causes in the

printer. If the banding does rotate with the image, then look for causes

in the computer/RIP or application.

Common Banding Causes

1. Uneven drying. Adjust the drying time to compensate for varying

ink percentages and media types. Dry time values range from

10 seconds to 60 minutes. This is especially important in higher

humidity environments.

2. The RIP (Raster Image Processor) and print cycles. We

recommend printing to a file first and then queuing the file to

the printer to avoid the RIP and print cycle delays that can

cause banding while printing.

3. Uneven inkjet kogation (partial clogging or orifice restriction) on

the inkjet cartridge head nozzles. Run the 100% color test and

re-prime or replace the cartridge if necessary.

4. Lower quality print modes normally cause slight bands, to avoid

this banding, switch to 4-pass or 6-pass printing modes.

5. Air bubbles in the ink delivery system. This indicates a loss of

negative pressure within the ink cartridge or ink delivery

system, check all quick release fittings and connections for

possible leaks and ensure that the cartridge is primed properly.

6. Improper priming. The lower secondary chamber within the

cartridge may de-prime and then temporarily recover after

entering the service station causing a momentary color drop out

in the print if the cartridge is improperly primed. Please

reference Technical Bulletin #97 for a more detailed

explaination and the corrective priming procedures.

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