Advantage Sign Supply Tech

We receive many calls on the topic of banding occurring with wide format solvent printers. Below are some of the more common causes and solutions to eliminate this issue.
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Cause 1: Not all of the nozzles in the printhead are firing properly.

Solution 1: Run a nozzle test print to verify that the print head is working properly. If the test print is poor, work on cleaning the print heads and the parts of the printer that clean the print heads.
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Cause 2: The printer is not feeding the media at the proper rate.

Solution 2: Adjust the Media Feed Rate on the printer.
1. If there are white gaps between the passes, lower the rate.
2. If there are sharp dark lines between the passes, increase the rate.
3. If the roll has a lot of media on it, the printer will feed at a different rate than with a roll that has very little media on it.

Check to make sure the inside edge of the media roll (cardboard tube) is not bend or frayed. If it is, this may cause a different feed rate from one side of the printer to the other. Try to get a perfect circle tube and use a utility knife to cut away excess part of the cardboard tube.
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Cause 3: The environment around the printer is out of range.

Solution 3: Temperature and humidity can affect the quality of the prints. For most printers you will want to keep the environment at 72°F ±7°F and 50% ±10% humidity. The further the environment is from these optimum settings, the greater the chances of seeing banding in the prints.

During summer times, high humidity in the air will cause the ink to not dry fast enough.
1. Raise the heat settings
2. Print slower by changing the print speed in the ripping software.
3. Print uni-directionally instead of bi-directionally.
4. Increase the number of passes.
5. Decrease the humidity in the air.
6. Print at the highest number of passes for your printer

During winter times, low humidity in the air will cause the ink to dry too quickly
1. Lower the heat settings
2. Print faster by changing the print speed in the ripping software.
3. Print bi-directionally instead of uni-directionally.
4. Lower the number of passes.
5. Increase the humidity in the air.
6. Print at the highest number of passes for your printer

Because of the low humidity during winter times, static electricity may cause irregular prints. Anti-static mats and grounding the printer may help with banding issues. However, the only sure way to solve this issue is by raising the humidity around the printer itself.

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If you have any questions about this post, please  leave a comment,  e-mail us at techteam@advantagesignsupply.com, or give us a call at 800-251-0929 and we will do our best to answer any questions you may have.