- Thread starter
- #41
- Joined
- Jan 4, 2012
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- Location
- UK
- Printer Model
- Canon Pro9000 II
Having gently flushed the print head red channel many times, it has not improved the nozzle check printout.
I found the 5mm PVC tubing useful in 6 inch lengths to provide a column of cleaning solvent (windex or W5 + 1% ammonia) for a slow flush of each channel simultaneously. The 5mm size was a little too large to provide a good tight fit on the input filters, but rapping the end of the tube tightly with PVC adhesive tape, corrected this.
Making up a 20mL syringe with a length of flexible tubing to fit the input filter, proved to be the best way to visually see that the nozzles were unblocked. Clamping the print head upside down and applying gentle pressure to the syringe filled with W5 cleaning solvent, it was possible to see fluid rising from the relevant nozzles and then being drained back with a slight vacuum applied.
If the nozzle test is to be believed, the inference is that some of the red channel nozzle circuit elements have failed, without any physical evidence of a clog or other cause. The red channel is one of the least used and until recently functioned normally in nozzle tests. One wonders whether Canon print heads are as durable as they should be for such an expensive item.
The only consolation is that the printer can perform without the red channel working by avoiding paper settings of Paper Pro II and Paper Pro Platinum and even using these paper modes in most cases there is no visible loss.