I recently had a call from a client who is using a third party ink from a UK based supplier however this ink is Imported from the far east. Although this ink is quite cheap it does not come with all the variety of cleaning agents and small ground pigments required to keep a machine flourishing.
The printer was a Epson 7900 which is an 11 colour machine. The client called me as I am an Epson approved engineer stating they had lost nozzles on the Cyan head.
As you can see the cyan is all blocked out and the Yellow also has become blocked.
After investigation I checked out the ink selector and this was clogged in most of the channels to some degree or other.
The conclusion is the print head itself. Print head for this machine costs circa £1100 then its a good four hours to correctly install and calibrate the machine afterwards. Expect a bill of around £1600 +vat.
Now this ink is roughly 15% cheaper than our Ink, however our ink has all the correct ingredients and cleaning agents and has never caused these problems.
I may fix this 7900 and resell so if anyone wants one get in touch.