Why Epson Printheads Use Glue Instead of Gaskets - And Why a Gasket Is Better for Repairs

Question:
In the video "Extreme Bone-Dry Printhead Cleaning: Recovering Epson Printheads Everyone Gave Up On," I noticed that a gasket was used when reassembling the printhead. Would it be possible to reseal the printhead the same way Epson originally did instead of using a gasket?

Answer:

To answer your question, the original Epson printhead in that video does not actually use a gasket. Instead, Epson permanently seals that section of the printhead using industrial adhesive (glue) during manufacturing. This type of seal is designed for one-time assembly only and is not intended to be opened and resealed during maintenance.

Once the printhead is disassembled, attempting to reseal it with glue again is generally not recommended for several important reasons.

1. Glue Can Easily Spread and Block Ink Channels

When trying to reseal the printhead using glue, the adhesive can spread unpredictably during assembly. The internal ink pathways inside Epson printheads are extremely small and sensitive. Even a tiny amount of glue that spreads toward the ink intake ports or internal channels can partially block the ink flow. This can cause symptoms such as:

• Persistent missing nozzles

• Poor ink flow or starvation

• Inconsistent printing

• Complete color loss in one channel

Because the tolerances inside a printhead are extremely tight, it is very easy for glue to create a new problem while trying to fix another.

2. Glue Seals Can Degrade Over Time

Another issue is that adhesive seals can break down over time due to ink exposure, pressure, and temperature changes. If the glue weakens or cracks, it may allow air leaks or ink leaks inside the printhead assembly.

Air leaks are particularly problematic because Epson piezo printheads rely on consistent ink pressure and vacuum balance. If air enters the system, you may experience:

• Random missing nozzles

• Air bubbles in ink lines

• Failure to prime ink

• Recurring clogging

3. Higher-End Epson Printheads Use Gaskets

Many higher-end Epson printheads actually use precision rubber gaskets or seals instead of glue. These gaskets create a controlled compression seal that is both reliable and serviceable.

A gasket has several advantages:

• Provides a clean and consistent seal

• Prevents glue contamination of ink channels

• Allows disassembly and reassembly during maintenance

• Maintains seal integrity under pressure and temperature changes

However, in lower-cost or disposable-style printheads, Epson often chooses adhesive sealing instead of a gasket simply to reduce manufacturing cost. These printheads are designed as non-serviceable components, meaning Epson expects the entire printhead to be replaced rather than repaired.

4. Why We Use a Replacement Gasket in Repairs

When repairing these printheads after disassembly, we install a gasket instead of trying to recreate the original glue seal. This provides a much safer and more reliable way to restore the internal seal without risking contamination of the ink intake system.

If you are performing similar maintenance, you can obtain the replacement gasket here:

Printhead Internal Gasket (FA040XX)
BCH Technologies Product Page (https://bchtechnologies.com/products/fa040xx-printhead-gasket-internal-seal-for-epson-printhead-maintenance)

This gasket allows the printhead to be sealed properly after cleaning or internal servicing.

Addressing printer issues can be complicated because many problems require hands-on inspection and mechanical work. For that reason, we are unable to provide remote troubleshooting or repair guidance for specific printer repairs. However, we do offer an in-person diagnostic and repair service through our local facility. You can learn more here: BCH Technologies Printer Repair Service (https://bchtechnologies.com/printer-repair-service). Due to high demand, repairs are handled on a first-come, first-served basis, and it may take a few weeks before we are able to accept a printer for drop-off.

Our services are designed to repair either entire printers or individual components, with clear instructions on how to proceed. That said, we understand our service rates may not always be the most economical option. Because of this, we strongly recommend exploring self-help resources whenever possible.

A great place to start is YouTube. You can visit our channel homepage here: BCH Technologies YouTube Channel (https://youtube.com/@bchtechnologies). Once there, use the search icon next to the "About" section on the right side of the menu bar to look for videos related to your specific printer issue. I receive dozens of messages every day asking whether we have a video for a particular repair topic. Since we've created videos for over nine years, it's difficult to remember every single one. Using YouTube's search feature is the fastest way to locate the right content. Additionally, YouTube may recommend helpful videos from other creators that could assist with your repair.

Thanks again for reaching out and for your continued interest in our work. We truly appreciate your support and engagement with BCH Technologies.