Previous Page | Next Page Contents Glossary Index Taking care of problems >

Print quality problems

Many print quality problems are directly related to the kind of forms that are being used and the application that is being processed. If a particular form or application regularly produces unsatisfactory output, refer the application owner to the Forms Design Reference for Continuous Forms Advanced Function Printers, G544-3921. This publication contains detailed information about selecting forms and designing applications for use with continuous forms printers.

The following table describes possible print quality problems and suggests actions that may correct the symptoms.

Table 12. Print quality symptom table
Symptom Action
Repeating spot patterns Clean the printer and the oiler belt. See Cleaning the printer and Cleaning the oiler belt.
Print is too dark or characters appear too wide Refer to "Creating a Snapshot" in the Planning and Configuration Guide to adjust the contrast.
In duplex printing mode there is a noticeable difference in the printing contrast between the front and back sides of the form, even though the Contrast Switch setting is set the same on both printers. It is normal for printing contrast to vary between printers. Adjust the contrast setting for both printers to balance the contrast between the printers. Refer to "Creating a Snapshot" in the Planning and Configuration Guide to adjust the contrast.

See Engine print balancing procedure.

Blank spots (voids) or light areas appear near perforations. This problem is usually related to forms design, and it cannot be corrected by adjusting the printer.

The following restrictions, copied from the Forms Design Reference for Continuous Forms Advanced Function Printers, G544-3921 must be maintained.

Print quality may be poor when printing near folding perforations, an internal perforation, or any cut in the form. To ensure correct operation and print quality, maintain the following distances:

  • From non-folding and internal perforations: 1.27 mm (0.05 in.)
  • From folding perforations:
    • For text, OCR, and bar codes: 8.5 mm (0.33 in.)
    • For images and solid-area fill: 12.7 mm (0.5 in.)
  • From binder holes and cuts: 2.54 mm (0.1 in.)

If the specified distance from the page perforations is not being maintained, refer the application owner to the Forms Design Reference for Continuous Forms Advanced Function Printers, G544-3921.

Loss of edge definition or lighter print contrast (boldness) at the trailing edge of bar codes, shaded or solid fill areas, or formatted bold text characters. The problem can be reduced or eliminated by increasing the contrast. Remember to adjust the contrast setting on both printers to balance the contrast between the front and back of the forms.

See Engine print balancing procedure.

Refer to "Creating a Snapshot" in the Planning and Configuration Guide to adjust the contrast.

Blank spots (voids) or light areas not near perforations
  • Ensure that the forms are smooth and flat. Feel the forms, especially near the perforation. If you find lumps, bumps, or wrinkles, load another box of forms. This kind of problem can be caused by storing forms in a poor environment (for example, high humidity).
  • Clean the coronas. See Cleaning the printer.
  • Refer to "Creating a Snapshot" in the Planning and Configuration Guide to adjust the contrast.
Print has white streaks
  • Clean the coronas. See Cleaning the printer.

    If necessary, remove the coronas and look for forms chads in the wire or corona housing. Be careful not to touch the wire with your hands. See Cleaning the printer.

Print is too light
  • Refer to "Creating a Snapshot" in the Planning and Configuration Guide to adjust the contrast.
  • Clean the coronas. See Cleaning the printer.
  • If an operator opened and closed the developer drain without replacing the developer mix, replace the developer mix now. Opening the drain resets the developer mix usage timer, which could result in the developer mix being used beyond its normal life and result in immediate print quality problems. See Changing the developer mix.
Print rubs off easily
  • If print rubs off solid fill areas (logos, bar codes) on the form, lighten the contrast until fuse grade is acceptable. Remember to adjust the contrast setting on both printers to balance the contrast between the front and back of the forms.

    Refer to "Creating a Snapshot" in the Planning and Configuration Guide to adjust the contrast.

  • Ensure that the hot roll temperature and the oil rate are set correctly for the forms being used.

    Use "Creating a Snapshot" in the Planning and Configuration Guide to adjust the fusing temperature and the amount of fuser oil used during printing.

  • Ensure that the preheat platen temperature is set correctly for the forms being used.
  • Clean the oiler belt. See Cleaning the oiler belt if you need instructions.
  • Ensure that the forms were fused. For example, did you use Forms Feed when you should have used NPRO?
  • Ensure that the hot roll shield is up.
  • Load a different box of forms. The forms you are running may be too heavy (more than 160 g/m2 [42 lb] when running simplex mode, or more than 105 g/m2 [28 lb] when running duplex mode), or too moist, or have too rough a surface.
Print is offset (double images)
  • Use "Creating a Snapshot" in the Planning and Configuration Guide to adjust the fusing temperature and the amount of fuser oil used during printing.
  • Clean the oiler belt. See Cleaning the oiler belt if you need instructions.
  • Ensure that the hot roll shield is up.
Print is not correctly registered
Dark background or dirty prints Clean the printer, particularly the coronas and the oiler belt. See Cleaning the oiler belt and Cleaning the printer.
Dark streaks Clean the printer, particularly the coronas and the oiler belt. See Cleaning the oiler belt and Cleaning the printer.
Dark or fuzzy 0.5-inch (12-mm) wide band across width of page (print bloom); characters appear bolder or slightly larger than normal This problem may occur at the point where pages stop in the fuser. The problem may also be application-related, and if so, cannot be corrected by adjusting the printer.
Any other print quality problem or any of the above problems that persist after you have followed all of the corrective steps Call your service representative. See Service call procedure.