How to Install Dampers on the Epson ET-8550 and Where to Find ET-4700 Mainboard & FFC Cables (Detailed Q&A Guide)

Question: How do I install dampers on an Epson ET-8550? Also, where can I find the mainboard and the FFC cable that connects the mainboard to the screen board for an Epson ET-4700?

Answer:

Installing Dampers on the Epson ET-8550

The Epson ET-8550 does not come with traditional dampers like older Epson models or dedicated DTF/DTG printers. However, when converting the ET-8550 for DTF, some technicians choose to modify the ink delivery system by installing inline dampers or third-party dampening assemblies.

Here are the key considerations and steps:

1. Understanding the Ink Pathway

The ET-8550 uses Epson's EcoTank system, where ink travels continuously from the reservoirs through tubes into the printhead. Unlike cartridge-based printers, there is no built-in damper block. When users say they want to "install dampers," they are usually referring to:

• Inline dampers on each ink line.

• A custom manifold that imitates traditional damper systems.

These modifications are not Epson-supported and require technical expertise.

2. When Dampers Are Useful

Dampers are typically added to address:

• Ink backflow issues

• Pressure stabilization

• Ink starvation during DTF printing

• Preventing contamination from air pockets

If you're experiencing inconsistent printing or ink starvation, a damper install may help-but only if done correctly.

3. General Steps for Inline Damper Integration

(These steps are general guidance based on industry knowledge; specific kits or printers may require variations.)

1. Access the Ink Tubes:
   Remove the printer cover and locate the ink lines leading to the printhead assembly.

2. Identify the Proper Cut Points:
   Dampers are inserted inline, so you'll need to cut the tubing between the tanks and the head.
   Warning: Cutting tubes incorrectly can cause irreversible leaks or pressure issues.

3. Mount the Dampers:
   Dampers must be positioned close enough to the printhead to be effective but secured firmly to avoid vibration.

4. Prime the Dampers:
   Before reinstalling the assembly, fill the dampers with ink using a syringe to remove trapped air.

5. Run a Nozzle Check:
   After reassembly, run a nozzle test to confirm stable firing.

Because the ET-8550 is a delicate machine with tight internal space, this type of modification should only be performed by someone comfortable with advanced printer repair. Mistakes can easily damage the printhead.

Finding the Mainboard and FFC Cable for Epson ET-4700

You also asked about the motherboard (mainboard) and the FFC cable that connects the mainboard to the screen board of an Epson ET-4700.

These parts are available through our store:

➡ BCH Technologies Website (https://bchtechnologies.com)

If you have trouble locating the exact ET-4700 parts:

• Send us an email at support@bchtechnologies.com, and we'll direct you to the correct listing or order the part for you if it's not currently online.

The mainboard and the screen-to-mainboard FFC cable are model-specific, so it's important to ensure accurate matching based on:

• Printer model (ET-4700)

• Revision number

• Pin count and length of the FFC

If you're replacing the cable due to display issues, streaky UI activity, or intermittent display failure, the FFC is the common culprit. If the printer is showing no power or random error codes, the mainboard is more likely the root cause.

Additional Notes on Error Behavior

While your question did not reference specific error codes, common ET-4700 hardware-related errors include:

• 0x97 (general hardware error)

• 0x9A (mechanical or board-related issue)

• E-11 / E-12 (communication errors between components)

A faulty FFC cable between the display and the mainboard can cause:

• Frozen screen

• Blank display

• Random restarts

• Failure to respond to button presses

A faulty mainboard may result in:

• Total failure to power

• Repeated boot-looping

• Sudden shutdowns

• Multiple unrelated error messages

Replacing the board or the cable generally resolves these issues.

Important Service Note

Dealing with hardware problems can be hands-on and complex. Because of this, we're unable to offer remote troubleshooting or step-by-step repair support. We provide in-person diagnostic and repair services through our shop, which you can learn more about here:
➡ Local Diagnostic Facility for Repairs (https://bchtechnologies.com/printer-repair-service)

Demand is extremely high, so work is done on a first-come, first-served basis, and wait times can reach a few weeks. We repair entire printers or individual components with clear instructions on how the process works. However, our pricing may not always be the most economical option.

For DIY troubleshooting, we strongly recommend using online resources. A great place to start is our YouTube homepage:
➡ BCH Technologies YouTube Channel (https://youtube.com/@bchtechnologies)

You can use the search bar (next to the "About" tab) to find videos related to your specific issue or model. We produce many videos, and YouTube may also suggest helpful content from other creators.

Thank you again for contacting us and for your continued support. We truly appreciate your patience and your dedication to keeping your printer running smoothly. If you need help finding a specific part on our site, don't hesitate to email us at support@bchtechnologies.com.