First ensure that the print head is clean. Clean using a cloth with isopropanol. Or replace. Typically if the decreased quality is caused by worn or dirty printhead is if the print is missing in lines through the label in the printing direction (caused by dirty/burned dots).
- Lower the print speed
- Increase the contrast
These two affect each other. When print speed is low the contrast can be set lower, that will improve print head life span. If the line capacity is high then the print speed might need to be high. If the line capacity allows, try to lower print speed down to about 160mm/s.
Print Roll Worn¶
A worn out print roll could also cause dispensing problems due to skidding of the label lining.
Print Profile Pressure¶
On the top of the print profile there is a Spring plate whose function is to press the print profile down towards the labels. After a while the plate can be bent, e.g. if the printer is hanging upside down, them print profile falls down when opened, or if the print profile is grabbed when lifting the printer. As a temporary solution it may help to flipp the spring plate so the bending is switched from concave to convex. Note that this increases the printhead pressure beyond recommendation which may have a negative effect on the print head life.
Outer Support Shaft / Stabilizing Bar (Outer)¶
Press on the support shaft (see above), there are springs underneath - so the shaft should be springy and return back to its position when released. It could happen that the shaft is stuck in one end, causing bad pressure and print quality. In this case contact the Evolabel support team.
Labels and Ribbon¶
If the print quality is bad even when using low print speed there could be a problem with label or ribbon quality (if ribbon is being used).
Print Out Compressed¶
The printout gets compressed in the feeding direction.
This is when the media is skidding onto the print roll.
I.e. the media does not move at the same speed as the print roll.
This is usually caused by a unclean, worn or damaged print roll.
Gray Stripe on Label¶
When using ribbon a gray stripe may appear on top of the label.
The gray line is caused by the ribbon moving at a different speed or direction than the label. To get rid of the line by setting the Ribbon Forward and Backward torque. Increase Forward torque to 35 or more. The perfect setting depends on label size, print speed and ribbon quality.
When using ribbon, thin diagonal lines may be seen on the label. These lines may be caused by ribbon wrinkling.
Start to remove the used ribbon from the rewinder. It’s harder to get a good result if the ribbon already on the rewinder is uneven.
- The wrinkling may be cured by the used of settings.
- must be greater than
- The difference between and should not be greater than 10.
- Try to adjust some (and consequently also ), +- 5 to 15 units.
Asymmetric layouts, where there are significantly more black on one half of the printhead may cause ribbon wrinkling. E.g. if there is a ladder directioned barcode close to the label right or left edge.
- Contrast setting
A too highmay melt the ribbon. This will not only damage the printhead but also prevent the ribbon from moving at correct speed.
If this won’t help it may be a printer mechanical issue. You may see wrinkling if the TT rewinder shaft is not parallel to the printhead profile. Verify that the TT rewinder shaft is not wobbly when turning. It may be damaged if e.g. used for lifting the printer. Consult the Evolabel Support team if you suspect an issue with the TT rewinder shaft
For good barcode readability, the lines in 1D barcodes and the pixels in 2D barcodes are to be crisp. There should be a distinct difference between black and white with no fuzzy area in between.
How crisp the lines are depends on many factors where the most important are:
- Physical media used
- Print speed
- For thermal transfer printing, the combination of media and ribbon used are also of big importance.
Because of printer physics, it is easier for the printer to print a high quality barcode in ‘picket fence’ direction than in ‘ladder’ direction.
The printout does not look like it should. Parts of the printout are recognized, but printed at incorrect positions.
This is a symptom when a printer with an incorrect printhead width has been selected. Verify that the correct model has been selected.