How to Fix Vertical Lines on an Epson 1390 DTF Printer (EraSmart) – Troubleshooting Guide

Question: My EraSmart 1390 DTF printer is leaving a line going down the prints. I already cleaned the roller bar and checked the printheads; they’re not clogged. What could be causing this issue?

Answer: 

Identifying the Type of Line

You mentioned that the line goes "down" your prints, which typically indicates a vertical line (aligned with the paper feed direction). This is an important distinction because horizontal lines (parallel to the printhead’s side-to-side movement) usually point to issues like banding, clogged nozzles, or uneven platen gaps.

Cause: Ink on the Carriage Return (CR) Belt

Based on your description, it’s highly likely that your issue stems from a small ink smear on the CR belt—the transparent plastic belt located behind the printhead carriage.

This CR belt helps the printhead move back and forth smoothly. If there's even a tiny spot of ink or debris on it, the belt may cause the printhead to jolt slightly or misalign, translating into unwanted vertical lines or streaks on your DTF prints.

Recommended Fix

Here’s what you can do to resolve the issue:

1. Please turn off the printer and unplug it to avoid any electrical risks.

2. Open the printer cover and manually move the printhead carriage to the center.

3. Locate the clear CR belt behind the carriage.

4. Use a lint-free cloth lightly dampened with isopropyl alcohol (at least 90%).

5. Gently clean both sides of the CR belt. Make sure to remove any visible ink residue.

6. Let the belt air-dry completely before plugging the printer back in.

Be very gentle—too much pressure or twisting can damage the belt. After cleaning, print a few test pages to confirm if the issue has been resolved.

Other Possibilities

If cleaning the CR belt does not resolve the problem, consider checking these additional areas:

• Encoder Strip Contamination: This is a transparent plastic strip that runs parallel to the carriage path and helps the printer determine printhead positioning. Ink splashes on it can also cause print anomalies.

• Roller Bar Staining: Even though you mentioned cleaning it, ensure there's no residual ink on the platen rollers or the pressure rollers above the media path.

• DTF Film Curl or Buckle: If the film isn't lying flat, the printhead could drag across it, causing a streak.

• Static Issues: Especially in dry environments, static buildup can attract dust or misguide ink spray. A grounding wire on the film path might help reduce this effect.

Addressing printer issues can be a complicated affair due to the hands-on nature of the problems. So, we cannot provide remote troubleshooting, suggestions, or support for printer repairs. We offer an in-person evaluation and repair service via our local diagnostic facility (https://bchtechnologies.com/printer-repair-service). Given the high demand, we operate on a first-come, first-served basis. So, it might take a few weeks to get your printer to drop it off. Our services are structured to repair the whole printer or specific parts, with clear instructions on how to proceed. However, we acknowledge that our rates aren't the most economical. Thus, we highly recommend that you resort to self-help via online research. You can start by checking out YouTube or visiting our YouTube channel's homepage (https://youtube.com/@bchtechnologies). Look for specific videos using the search icon next to "About" on the right-hand side of the menu bar. I receive dozens of queries every day asking about videos for specific topics. Having created videos over the past nine years, it's challenging to remember every single one. Therefore, using YouTube's search function would be most efficient. Plus, YouTube might suggest relevant videos from other channels that could assist you.

Thank you again for trusting BCH Technologies to answer your printer questions. Your active engagement helps us provide better answers and stronger solutions for the printing community.