Epson L1800 DTF Printer White Ink Stops Mid-Print: Causes and Fixes

Question:

I have an Epson L1800 converted for DTF printing. When I print smaller designs around 5-6 inches, both color and white underbase print perfectly. However, when printing larger designs (about 9-12 inches), the white underbase fades or disappears halfway through, especially when the print includes breaks or multiple rows of images. It seems like one white printhead stops firing.

I've already tried several fixes-head cleaning, power ink purges, cleaning the capping station, and even syringing the white ink lines to confirm good flow. Everything seems fine. I noticed one white damper often builds up vacuum pressure while the other flows well. After switching the white dampers, the print completed perfectly and there was no vacuum on the problematic damper. What could cause this, and how can I prevent it from recurring?

Answer:

From your description, this does not sound like a clogging issue, but rather a white ink supply problem related to vacuum buildup in the damper or manifold area. Let's go over what could be happening and the possible fixes in detail.

1. Understanding the White Ink Flow Problem

DTF printers like the Epson L1800 are sensitive to vacuum pressure in the white ink line. The system relies on consistent negative pressure from the damper to draw ink from the tank through the printhead. When one of the dampers begins to hold excessive vacuum, the ink flow stops temporarily, leading to the fading or total loss of white ink during longer prints.

Because your smaller 5-6 inch prints complete fine, the problem likely occurs over time-as the vacuum builds, ink flow is gradually restricted. The fact that you can later print a perfect 3x3 white square confirms that your nozzles and head are not clogged.

2. The Role of Dampers and Manifold Pressure

Dampers are small chambers that regulate ink pressure before it enters the printhead. Over time, they can wear out, trap air, or lose elasticity, resulting in uneven pressure between white channels. When you switched the dampers and saw normal performance, it confirmed the issue lies in that particular damper's airflow or seal.

If the replacement damper temporarily solved the issue but it reappears later, the manifold (the ink distribution component attached to the printhead) could be contributing to the vacuum problem. Ink buildup or micro-air leaks at the manifold's O-ring connection can prevent proper pressure equalization.

You can carefully remove and clean the manifold on the printhead, ensuring a snug, airtight fit when reassembling. Always handle this part gently to avoid cracking the plastic or damaging the sealing surfaces.

3. Installing a Secondary Tank System

To further stabilize white ink pressure, consider installing a secondary tank system, which allows air to escape and balances pressure during longer prints. BCH Technologies offers a reliable option:
Secondary Tank for DTF Printhead (3 mm OD) (https://bchtechnologies.com/products/secondary-tank-for-dtf-printhead-3-mm-od-1?_pos=1&_sid=47d55ce67&_ss=r).

This secondary tank helps prevent vacuum buildup by allowing ink to flow more consistently, especially during extended printing sessions or when printing designs with large white areas.

4. Additional Tips

• Ensure your ink lines are not kinked or overly long, as this increases resistance and can worsen vacuum issues.

• Regularly agitate the white ink tank before long prints, as white pigment tends to settle and thicken, contributing to inconsistent flow.

• Check that the capping station seal is intact-any air leak during printing can impact suction and ink delivery balance.

Addressing printer issues can be a complicated affair due to the hands-on nature of the problems. We're not able to provide remote troubleshooting, suggestions, or support for printer repairs. However, we do offer an in-person diagnostic and repair service via our local facility (https://bchtechnologies.com/printer-repair-service). Our operations are on a first-come, first-served basis, and it may take a few weeks before a printer can be dropped off.

Our services cover full printer repairs or specific part replacements, with clear instructions for each case. While our rates may not be the lowest, we encourage self-research as a more affordable alternative. You can begin by exploring tutorials on YouTube (https://youtube.com/@bchtechnologies). Use the search icon next to "About" on our channel page to find videos tailored to your issue-YouTube may also suggest other relevant videos from different creators.

Thank you again for your patience and for reaching out to BCH Technologies. We truly appreciate your dedication to learning, maintaining your printer, and sharing your experiences with us.