My i9900 also stopped printing black this week. While searching for help, I came across this thread.
In regard to the instructions on how to disassemble and clean the i9900 print head...
This worked exactly as described above. However, I had already destroyed the integrated circuit, so I had little to lose.
After disassembly, I did observer that if you hold the ceramic print head up to a bright light, you can actually see through it and see where the clog is, if the head itself is clogged. This was a surprise!
I also discovered that a syringe that comes full of thermal paste with a cpu chip is the perfect size to fit both over the nozzles on the bottom of the plastic base piece and over the sponges on the top of the plastic base! Of course you have to clean it out first! This makes it easy to gently flush the plastic piece from both directions. I flushed it with alcohol. My black had been severely clogged. I found that after a couple gentle flushes in both directions that the clog dissolved. I also found that under gentle pressure on the syringe, alcohol should flow freely and squirt out of the other side. If it does not, flush a few more times and it will. As it turns out, three other colors were slightly clogged.
On re-assembly, I found that the circuit board will just stick on the four posts, just not as tight as it had been.
Finally, I found that Precision Roller sells replacement print heads for $109.50. Ordered today - if I have any trouble with them, I'll post a followup.
http://www.precisionroller.com/category.php?curr_page=2
But as Grandfather noted above, an ounce of prevention is far better than having to worry about the print head at all!
With less expensive refill options, I'll be sure to print more frequently.
Thanks for all the great info and suggestions!
In regard to the instructions on how to disassemble and clean the i9900 print head...
This worked exactly as described above. However, I had already destroyed the integrated circuit, so I had little to lose.
After disassembly, I did observer that if you hold the ceramic print head up to a bright light, you can actually see through it and see where the clog is, if the head itself is clogged. This was a surprise!
I also discovered that a syringe that comes full of thermal paste with a cpu chip is the perfect size to fit both over the nozzles on the bottom of the plastic base piece and over the sponges on the top of the plastic base! Of course you have to clean it out first! This makes it easy to gently flush the plastic piece from both directions. I flushed it with alcohol. My black had been severely clogged. I found that after a couple gentle flushes in both directions that the clog dissolved. I also found that under gentle pressure on the syringe, alcohol should flow freely and squirt out of the other side. If it does not, flush a few more times and it will. As it turns out, three other colors were slightly clogged.
On re-assembly, I found that the circuit board will just stick on the four posts, just not as tight as it had been.
Finally, I found that Precision Roller sells replacement print heads for $109.50. Ordered today - if I have any trouble with them, I'll post a followup.
http://www.precisionroller.com/category.php?curr_page=2
But as Grandfather noted above, an ounce of prevention is far better than having to worry about the print head at all!
With less expensive refill options, I'll be sure to print more frequently.
Thanks for all the great info and suggestions!
