Best Practices for Running a CISS Pump and Agitator in DTF Printing

Question:
What is the best way to run your Continuous Ink Supply System (CISS)? Should I run the pump and agitator while printing, or only when not printing? What are the do's and don'ts?

Answer:

1. Agitator Operation

• The agitator can be run at any time to keep pigments-especially white ink-well suspended.

• You do not need to let it run continuously. A practical schedule is 30-40 seconds every 5 minutes. This keeps the ink properly mixed without putting unnecessary strain on the motor or power supply.

• Running it occasionally is enough to prevent pigment settling, which is particularly important for DTF printing.

2. Pump Operation

• The pump requires more careful attention than the agitator. Its purpose is to maintain ink pressure and flow through the system.

• Watch the print closely:

  • If the pump is running and you notice white ink cutting off during printing, it means the pressure is too high.

  • If you see frequent air bubbles in the white ink line, the pump may be running inefficiently or not long enough.

• A good practice is to run the pump for 8-15 seconds right after the mixer/agitator has run. This primes the line without over-pressurizing.

3. Running Pump and Agitator Together

• You can run both at the same time, but this requires your power supply to support the combined load.

• If your printer's performance seems to dip or the print is interrupted when both are running, stagger them instead of running simultaneously.

4. Additional Stability - Secondary Tank Setup

• If you notice that the pump interrupts printing or the flow is inconsistent, consider installing a secondary buffer tank positioned just above the printhead.

• This small tank helps stabilize pressure and ensures a smooth flow of white ink. It is not always necessary but can make a big difference in preventing interruptions.

5. Do's and Don'ts

• ✅ Do run the agitator periodically to keep pigments suspended.

• ✅ Do use short, controlled pump cycles (8-15 seconds) after agitation.

• ✅ Do observe your prints carefully-ink behavior is the best indicator of whether adjustments are needed.

• ❌ Don't run the pump constantly, as it may flood the head or cause pressure fluctuations.

• ❌ Don't ignore bubbles in the line-this signals a priming or pump cycle adjustment is required.

• ❌ Don't assume all setups are identical-each system may require fine-tuning based on your ink, environment, and hardware.

Addressing printer and CISS issues can be complex because they require hands-on observation and adjustment. For this reason, we cannot provide remote troubleshooting or direct repair support. However, we do offer an in-person evaluation and repair service (https://bchtechnologies.com/printer-repair-service). This service is first-come, first-served, and due to high demand, it may take a few weeks before your printer can be worked on. We repair both full printers and specific components, but we also recognize that our pricing may not be the most economical. Many customers choose to begin with self-help, and a great resource for that is our YouTube channel (https://youtube.com/@bchtechnologies). Use the search icon next to the "About" tab to look for videos on CISS operation, pump adjustment, and white ink management, or let YouTube suggest related tutorials from other experts.

Thank you again for reaching out. Your support and questions help us continue building better resources for the printing community.