Troubleshooting DTF Ink Flow Issues on Epson ET-8550 After Conversion: CISS, Dampers, and Printhead Problems Explained

Question:

I'm using a newly converted Epson ET-8550 for DTF printing with your CISS system, updated dampers, and printhead cover. After manually priming the dampers by drawing ink into them, I still can't get a nozzle check or any ink to flow, even after head cleanings and a power cleaning cycle. The waste tube shows little to no ink when suctioned, predominantly black. There’s almost no resistance when pulling from the waste line. Could the issue be the printhead itself or the printhead height being set to the highest level?

Answer:

Understanding the Problem: Ink Not Reaching the Nozzles

What you’ve described—primed dampers that still don’t result in ink flow during nozzle checks or cleanings—is often a symptom of incomplete priming, sealing issues at the capping station, or clogging in the capping station or the printhead itself. Since you mentioned that drawing ink from the waste line gives you very little black ink and almost no resistance, it suggests one of two major culprits:

1. Poor seal or misalignment at the capping station

2. Partial or complete clogging within the printhead or dampers

Step-by-Step Guide: How to Park and Prime Your Printhead

Let’s make sure the printhead is properly parked and primed, a critical step especially after a new conversion:

1. Ensure Proper Parking
   Turn on your printer and let the printhead settle naturally onto the capping station. Do not manually push it into place. Parking it while powered on ensures correct alignment with the capping pad.

2. Use the Waste Ink Line for Priming
   Attach a syringe and tube to the printer’s waste line (coming from the capping station). Slowly draw out 2 ml of air.

   • At 1.5 ml, you should start to feel some resistance.

   • If you continue drawing and only get air, the printhead isn’t sealing properly, or the cap has an air leak.

   • If there’s no resistance, your capping station could be clogged or dried out, preventing a vacuum seal.

   • If there’s complete resistance, the capping station may be clogged internally, preventing ink from flowing.

3. Check for Damper Crinkling
   When the seal is correct, you’ll hear a crinkle or pop from the damper membrane as the suction opens the nozzle gates. This indicates that ink can now flow through the printhead.

4. Hold for 10 Seconds
   Once you've reached 2 ml and felt the appropriate pressure changes, hold the syringe in place for 10 seconds. This helps stabilize the ink channels and primes the system.

5. Run a Cleaning Cycle
   After priming, run a standard head cleaning from the printer’s maintenance menu. Avoid doing multiple strong cleanings back-to-back. Wait at least 12 hours before attempting another deep clean to avoid overheating the head or worsening ink bubble formation.

Additional Tips:

• Printhead Height Matters
  Raising the printhead too high can affect the pressure balance, especially with DTF ink, which is thicker and heavier than dye or pigment ink. Try lowering the printhead to its mid or default position, then attempt the steps above again.

• CISS Tubing Check
  Double-check the routing of your CISS tubes to ensure no air gaps, kinks, or loose fittings might be drawing in air instead of ink.

• Damper Seal Integrity
  A faulty or dry damper membrane can cause flow issues even after priming. If it fails to hold ink when disconnected from the printhead, replace it.

Addressing printer issues can be a complicated affair due to the hands-on nature of the problems. So, we're not able to 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. It may take a few weeks to get your printer to drop it off. Our services are structured to repair a 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 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.

Thanks again for being a part of our community. We genuinely value your questions and hope this helps get your DTF printer back in action!