- Joined
- Dec 27, 2014
- Messages
- 6,097
- Reaction score
- 7,275
- Points
- 363
- Location
- Germany
- Printer Model
- L805, WF2010, ET8550
There is a rarely covered issue with the ink supply in Ecotank printers, inks are fed via tubes to the printhead, actually to a damper which connects the tubes to the ink receptacles, the dampers, in the printhead. The printhead carriage is not changed vs. the baseline cartridge printers, the cartridges are replaced by dampers which provide some essential functions - feeding the ink to the printhead - filtering the ink with a very fine wire mesh filter - and providing a small ink reservoir.
The inks are not travelling with the printhead - the printer is moving the carriage back and forth - effectively moving the ink with the ink flow in the tubes or against the ink flow in the tubes.
This causes small pressure changes in the supply channels , and these changes are buffered, damped in the damper - with a small (elastic) air bubble and a small ink reservoir which is covered by a foil which can breath.
It now happens over time that the ink levels in the damper reservoirs drop - additional air gets into it, and the ink level drops below the filter, and the printhead is randomly pulling small amounts of air with the ink when printing. This leads to an effect which looks like clogged nozzles with random appearance and cannot really be cleaned away. The effect is very persistent if not taken care of.
But where is this air coming from ? There is no explanation in Epson maintenance manuals or elsewhere. But when you look around to a maintenance manual of Brother printers I found some interesting details. Brother printers use tubes since a long time to supply ink to the printhead, and the Brother printhead is designed such that it can take care of this problem. Brother printheads have an air trap built-in which gets released during cleaning cycles. I'm copying this text from the service manual:
'Liquid ink contains trace amounts of air. These molecules coalesce into air bubbles as the piezoceramic actuators vary the pressure on the ink in the ink-jet head channels. Removing as many of these bubbles as possible before the ink reaches the inkjet head is essential to maintaining proper print quality. A drawing shows how the damper assemblies provide air buffers .....for consolidating these air bubbles away from the inkjet head and vent flow paths for purging them at regular schedule intervals.'
I have observed this effect on about every ecotank printer I was using so far that the ink level in the dampers drops very slowly - getting more air into it, and dropping to a point that random nozzle problems show up. But there is quite an easy fix for it - pulling the dampers out from the printhead carriage and pulling ink into the damper - e.g. filling it up to 75% - with a syringe via the ink outlet, the ink outlet is spring loaded and closes when you pull the syringe away.
This is the damper for the magenta channel of a L1800, you need to remove a cover over the tubes with one srew and pull out the dampers one by one, they latch into the carriage the same way as cartridges would do.
The inks are not travelling with the printhead - the printer is moving the carriage back and forth - effectively moving the ink with the ink flow in the tubes or against the ink flow in the tubes.
This causes small pressure changes in the supply channels , and these changes are buffered, damped in the damper - with a small (elastic) air bubble and a small ink reservoir which is covered by a foil which can breath.
It now happens over time that the ink levels in the damper reservoirs drop - additional air gets into it, and the ink level drops below the filter, and the printhead is randomly pulling small amounts of air with the ink when printing. This leads to an effect which looks like clogged nozzles with random appearance and cannot really be cleaned away. The effect is very persistent if not taken care of.
But where is this air coming from ? There is no explanation in Epson maintenance manuals or elsewhere. But when you look around to a maintenance manual of Brother printers I found some interesting details. Brother printers use tubes since a long time to supply ink to the printhead, and the Brother printhead is designed such that it can take care of this problem. Brother printheads have an air trap built-in which gets released during cleaning cycles. I'm copying this text from the service manual:
'Liquid ink contains trace amounts of air. These molecules coalesce into air bubbles as the piezoceramic actuators vary the pressure on the ink in the ink-jet head channels. Removing as many of these bubbles as possible before the ink reaches the inkjet head is essential to maintaining proper print quality. A drawing shows how the damper assemblies provide air buffers .....for consolidating these air bubbles away from the inkjet head and vent flow paths for purging them at regular schedule intervals.'
I have observed this effect on about every ecotank printer I was using so far that the ink level in the dampers drops very slowly - getting more air into it, and dropping to a point that random nozzle problems show up. But there is quite an easy fix for it - pulling the dampers out from the printhead carriage and pulling ink into the damper - e.g. filling it up to 75% - with a syringe via the ink outlet, the ink outlet is spring loaded and closes when you pull the syringe away.
This is the damper for the magenta channel of a L1800, you need to remove a cover over the tubes with one srew and pull out the dampers one by one, they latch into the carriage the same way as cartridges would do.
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