From Photo Review Issue 45
From Photo Review Issue 45:
Printers in regular use normally require little additional maintenance. However, if you leave your printer for a week or more without using it, you may have problems with clogged nozzles in the print head, regardless of whether the printer uses dye or pigment inks.
When cartridges are inserted in the printer, their seals are broken and the liquid carrying the colours begins to evaporate very slowly. Pigment ink particles, which are one to two microns in diameter, may also drop out of suspension. With dye-based inks, impurities can react with the ink over time to turn it into sludge. Both will block the ultra-fine nozzles in the print head
Maintenance (or ‘Utility’) interfaces vary with different manufacturers but all contain the same three critical tools: Nozzle Check, Print Head Alignment and Head Cleaning. The Nozzle Check and Print Head Alignment tools are used to check that ink is being laid down evenly and in the correct position, while the Head Cleaning function lets you clear blocked nozzles in the print head if clogging has been identified in the Nozzle Check.
Maintenance options provided on the Canon Pixma Pro9000 Mark II printer.
The Maintenance interface on the Epson Stylus Photo 1410 printer.
Nozzle Checking and Head Cleaning
Nozzle Checking causes the printer to print a series of slanted lines on the paper using each of the ink cartridges. If these lines are continuous, the nozzles are clean. If there are gaps, the nozzle corresponding to that colour is clogged and the print head must be cleaned.
The user interface for the Nozzle Check function on Epson’s Epson Stylus Photo 1410 printer.
Some printers provide two Nozzle Check modes, an Auto mode that performs both nozzle checking and head cleaning automatically, and a Manual mode that is used when you simply wish to check whether any nozzles are clogged. In the Auto mode, the test patterns are slightly larger, which means more ink is used. However, they allow the printer to detect problems and determine how much head cleaning is required.
After each head cleaning another row of test patterns is printed and a further detection cycle is run. If the printer gets to the bottom of the page and still thinks further head cleaning is needed, it will stop the cycle and you’ll be left to decide what to do next.
When working in Manual mode, you can move directly from the Nozzle Check to the Head Cleaning function, which ‘cleans’ the nozzles in the print head by increasing the pressure used to force the ink through them. This should clear minor blockages – although it also uses ink. If you run another Nozzle Check and still find gaps in the test pattern, a further Head Cleaning cycle is required.
Each subsequent head cleaning cycle will increase the pressure progressively to force out persistent clogs. But you should also see an improvement in the nozzle check printout. If you run more than about six cleaning cycles and the nozzle check shows no improvement, one or more ink cartridges may need replacing or the printer may require servicing.
Some printers routinely run periodic auto nozzle checking and cleaning cycles. While this sounds like a useful procedure, it sometimes takes place when there is nothing wrong with the output and, after the auto check, output colours may be changed. Getting things back to the pre-check status can waste time and ink.
The user manual should provide instructions on how to turn off automatic nozzle checking – although you may need to dig deeply into the instructions to find them. Alternatively, a Google search on Turning off auto nozzle checking should take you to instructions posted online by various photographers.
Never run the cleaning utility without printing between runs. That can make the problem worse, because with some printers the cleaning process can cause air bubbles to accumulate in the ink lines. Consecutive head cleanings can increase the number and size of those bubbles. Printing in between cleaning runs – even if it’s only on a few sheets of plain office paper – gives the printer a chance to expel the bubbles.
As well as using valuable ink, head cleaning also causes the printer to discharge ink into a special maintenance cartridge which is provided to collect any ink that gets sprayed around inside the printer. (Borderless printing also causes ink to be dispersed and collected in the maintenance cartridge.)
The maintenance cartridge contains an absorbent padding that will fill up surprisingly quickly with repeated head cleaning. Once it’s full, the printer will stop until it’s been replaced.
Professional inkjet printers like the Epson Stylus Pro 3880 come with user-replaceable maintenance cartridges.
For many consumer-level printers, the maintenance cartridge can only be replaced by a service technician. Some enthusiast-level printers and most professional printers have user-replaceable maintenance cartridges. Your printer’s manual will provide details.
Occasionally, a broken pattern in a nozzle check printout can be caused by air bubbles in the line between the ink cartridge and print head. The best way to remove these bubbles is to print a lot of pages using the colour in which the blockage occurs. If you create a page with that particular colour in your image editor and print it a few times, there’s a good chance of clearing the blockage. However, you need to know the RGB values that correspond to the colour line you wish to clear.
The following are the RGB values for the most commonly-used ink colours:
Aim to cover at least 3/4 of the page with the colour. If you suspect more than one colour line is blocked, divide the page accordingly and fill different sections with the relevant colours. If the problem isn’t solved after printing six pages, the printer will probably require servicing.
Interchangeable vs Fixed Print Heads
Thermal inkjet printers need print heads that can withstand repeated heating and cooling and many manufacturers offer user-replaceable heads that allow consumers to replace print heads that have been damaged by constant use. A typical A3+ print head costs between $80 and $125, while A4 printer print heads are priced between about $40 and $100.
Piezo-electric technology uses a special type of crystal in the print head, which flexes when an electric current is applied. This changes the shape of the ink nozzle and forces a tiny drop of ink out without requiring the application of heat. The beauty of this system lies in the high degree of control it provides over droplet sizes.
Piezo-electric print heads are permanent and not user-replaceable because they are less likely to be damaged through normal usage than thermal print heads. The cost of replacing the head on an A4 printer is often close to the price of the printer itself. A3+ print heads for piezo-electric printers are typically priced between $260 and $300 and that doesn’t include labour costs.
To keep the printer running smoothly, piezo-electric print heads require inks with specific viscosities. If the ink is not viscous enough it will leak out through the nozzles, whereas inks that are slightly too viscous can clog print heads.
Print Head Alignment
The alignment pattern produced by the Epson Stylus Photo 1410 printer.
Patch number 5 was the smoothest looking in each of the three rows so the number 5 is entered in each of the boxes to complete the alignment.
Changing Ink Cartridges
The warning message (top) and ink status monitor (below) displayed by the Canon Pixma Pro9500 Mark II printer to show the Grey cartridge should be replaced.
Have a replacement cartridge ready before removing the depleted cartridge from the printer and make the swap-over as quickly as possible. The longer the cartridge is out of the printer, the more likely the heads will dry up and make the cartridge useless.
Be careful with printers that require you to remove one of the black cartridges when swapping between glossy and matte papers. Some manufacturers provide a special holder for the cartridge that’s not in use but, if none is provided, cover the ink outlet on the cartridge you’ve removed with the cover removed from the cartridge you’ve just inserted and place this cartridge in the plastic bag provided for the other cartridge. Seal it with tape to prevent the solvents in the cartridge from evaporating.
Most printer manufacturers caution users against using household cleaners and advise that a soft, lint-free cloth should be used for removing any dust or grime that may have collected on the printer. If the back of a printout is soiled, running a ridged sheet of paper through the printer can help to remove grime that may have collected on the bottom plate.
Instructions for cleaning the bottom plate on a Canon Canon Pixma Pro9000 Mark II printer.
A few printers come with built-in feed roller cleaning facilities that spin the rollers for a minute or two to remove residual dust. Follow the manufacturer’s instructions before you embark on any cleaning activities.
Turn Off the Printer Properly