Print Head & Cartridge Maintenance Tips for PhotoFrost Cake Printers
Before you curse and call your vendor for help and before you condemn defective cartridges and/or print head there are a few questions to think about, tests you can do and a couple of in-the-field 'fixes' you can try that just might get you up & running again, at least long enough to finish tomorrow's cake orders!
This article reflects many hours of research and documentation. Some of the credit goes to helpful customers who have assisted us in isolating problems and improving our products.
We would like to thank those people for contributing and helping us to make these instructions available to decorators worldwide who are embarking on the adventure of creating photo-printed confections.
GENERAL MAINTENANCE: A clean print head will give the best performance. Edible ink fluid in the journals can dry if not used regularly and cumulatively build up on the walls of the passages, imparing ink flow. A good maintenance habit is to clean the print head using the patent-pending PhotoFrost Power Flush Tool with hot water on a regular basis and use our Cleaner Cartridge Set periodically for preventative maintenance. Water pressure will force the hot water into the inlet nozzles and the heat will loosen buildup. To be sure the water has fully penetrated through the print head and completely cleared it of all residual color look for the full fan spray out the nozzles on the bottom of the print head. If the pattern is broken you still have obstructed print nozzles.
If you plan to store the print head for a time between uses it is good to clean it first. Dry carefully with a paper towel. This procedure will not harm the electrical contacts when done properly. If print quality has begun to degrade a hot water rinse may not be adequate for thorough cleaning. For detailed deep cleaning instructions see our Cleaning Video in this section. If you are sure your cartridges are not empty but you are getting poor qualty prints or missing colors in your pictures here are some simple tests to isolate a problem.
NOTE: INFO on MEMORY PROBLEMS
Occasionally poor print quality can be the result of insufficient memory in your computer. With today's powerful computers this is less likely, yet large picture files can cause memory bogging.
If printed cakes are very popular in your business you might think about having an additional printer as spare & backup. It is not expensive, it should use the same print head as your primary, it can keep you in business while your main printer is out of service, and we hope it will be printing every Thursday & Friday evening right along with your primary system.
(We hope you have that many PhotoFrost cakes to do!)
7 Beep Trouble Signal, or Flashing Orange Light
Typically these signals from your printer mean something is internally wrong and it must go to an authorized Canon Service Center for repair or replacement. However we have experienced a print head failure that caused this same signal. After replacing the print head, the printer resumed printing with no further problem. This may not always be the case but if you experience this trouble signal and you have another print head (known to be good), try it before you pack and ship your printer off.
We are seeing some cases where the environment (office or work area) where the printer is located is at lower-than-comfortable temperatures, specifically below 70 degrees F. We suspect that difficulties in color flow & print head blockages may have occured as a result of this type environment. Additionally, low humidity or very dry climate can contribute to inkjet nozzles drying and creating obstruction. We are currently recommending that the cartridges and print head be maintained at a working and storage temp of over 70F/20C. We are developing a solution to make our ink formula more resilient to these conditions. Another scenario happened when we found a printer had been placed directly below or beside an air conditioning vent. The high flow of dry air caused incessant difficulty in the printer performance. Please be aware of the environment your printer must cope with!
TIP: If you are having difficulty getting color to flow from a cartridge, the outlet wick may be dry. Try injecting a small amount (1 or 2cc) of hot water through the wick into the cartridge cell. This will prime & encourage flow.
The Canon style cartridges are a simple design with few parts. The cartridge or 'tank' is a casing with an internal wick that keeps the colors from leaking out the top vent hole. There is a filter, also called 'seal' or 'wick', that allows flow on demand through the bottom outlet hole. There is a vent hole in the top cover, sometimes under the upper cap. In a tri-color tank there are three separate color cells, each with its own wick. Each color cell has an individual vent hole in the cover.
Most models used in PhotoFrost printing from approximately 1998-on have individual tanks for each color. These have a vent hole visible after removing the yellow cover tape. Keep these cartridges stored upright to avoid leakage out the vent hole and assure the edible ink fluid stays primed at the wick ready to deliver. This will help avoid Vacuum Lock.
The vent holes must not be clogged. If the tanks have been stored up side down or laying on their side it is possible that the vent holes have become clogged, preventing air from entering the tank top and stopping fluid from exiting the bottom. You can test by tapping gently onto a paper towel. You should see a spot of color out of the bottom.
When installed, the print head nozzle pushes the wick slightly up into the tank. The wick presses against the sponge creating a tiny gap, allowing color to flow past to the head. If the wick is stuck or will not move slightly up into the tank it may hinder color flow. You can test by pushing gently on the wick with a pencil eraser. It should move easily upward and back down. Color may drip out. Be careful not to push it completely inside the tank. The travel is less than 1/8".
Where the cartridge seats in the print head there is a seal that is essential. If missing or stuck due to ink residue it can allow air to leak between the cartridge and inlet port, pulling air into the journals. Air bubbles in the print head channel will interrupt flow causing lines or even missing color. When you clean the print head you can carefully remove these seals to clean under them. Be sure to note they are in place before reinstalling the print head. A leaking seal can also allow a cartridge to empty itself of ink by draining into the print head, possibly overspilling the dividers and contaminating the other cartridges. This is not due to a faulty cartridge. This is illustrated in the video on Print Head Cleaning in this RESOURCE Section.
DO NOT refrigerate cartridges when not in use. When cooled it is possible for the colors to 'thicken' and inhibit proper ink flow.
You can try tapping the cartridge (not the print head) onto a peper towel on a hard surface to encourage fluid to travel to the bottom. You should see some color spotting through the wick.
Store cartridges with the orange cap snapped in place and upright. Be sure the silicone seal is present in the cover. This will encourage fluid to travel toward the outlets. Keep sealed in the zip bag they came in.
Another common cause of blockage and poor flow is long periods of printer inactivity. This problem is common to all inkjet printers. We recommend a minimum of a test print every other day to make sure it is working. This will be explained further in the section on print heads.
If you notice print quality degrading you may want to perform one or more cleaning cycles (printer properties window, maintenance procedures) and a test print on paper. If none of these things produce good results and you are sure there is no blockage in the print head a possible 'field fix' is to inject (with a sterile hypodermic needle) a small amount of Purified Water (1/2cc), through the wick into the color cell. Be aware this is a desparation procedure and should not become common practice. Addition of water may succeed in getting one last print from a depleted cartridge but continued addition will dilute the edible inks and imbalance the delicate fluid properties needed to allow flow through the print head.
Canon Print Heads
The print head is a somewhat delicate and intricate part. Generally speaking they are fairly reliable but they do sometimes fail and it is possible to wear one out. As a piece of equipment directly involved in daily business we recommend having a spare available. Again let me stress: DO NOT refrigerate when not in use.
On examination the head has several parts or sections. Inside, where the cartridges seat you can see the nozzles that mate with the cartridge wick. They have a screen top to allow color to flow through.
Around the nozzles is a rubber gasket that seals between the cartridge and inlet. This gasket must be properly in place to make a good seal. If out of place or damaged it can allow leakage of color into the well, possibly tainting the other colors. When you look at the wicks in the cartridges you should clearly see the bright primary colors; yellow, blue and red in the tri-color tank and black only in the black tank. If these colors are tainted you will get improper color in your picture prints. Also if the seal allows air to enter the print journals print quality can degrade and even permanent print head failure can occur. It is prudent to clean under the seals whenever you remove the cartridges.
Outside the head, on the side, is a contact board - the electrical portion of the head. These contacts match and connect with the contacts of the head carriage in the printer. Both sets of contacts must be clean and properly lined up so the electrical signal from the printer travels through the correct path and emits the proper color spray. If they appear dirty you can clean (gently) with a moist, soft, lint-free cloth or a pencil eraser. Be sure they are thoroughly dry prior to reinstalling.
We have seen only two instances where the printer carriage (the thing that the print head sits in) is faulty. In both cases this problem has revealed itself immediately when the new printer was installed.
The bottom of the head, at the edge of the contact board, has the outlets or 'jet nozzles'. This area is the most delicate part of the head and should be protected. It can be cleaned with a soft, warm, damp cloth that is lint-free. This is a common place for color to dry and create blockage.
Internally there is a passage or 'journal' from the nozzle to the outlet for each color. These journals are very tiny and each has a filament internally to heat ink. The heat creates a vapor which creates pressure to 'jet' the color through. If color is permitted to dry throughout a journal causing complete blockage it can be very stubborn or impossible to clear. If there is only a small buildup internally it can impare flow or hinder the element's heating capability causing intermittent color flow. This results is lines, missing color spots and generally poor quality printing. This is the most common cause of print head failure. If this filament is broken the print head must be replaced.
The best method to avoid blockages in the print head is frequent use and regular cleaning with PhotoFrost Power Flush Tool and PhotoFrost Cleaner Cartridges.
PhotoFrost Cleaner Cartridge Set has a special non-toxic mix formulated to penetrate & deep clean the journals of the print head and use the PhotoFrost Power Flush sprayer
We recommend doing this frequently and before a long period of non-use.
BE AWARE that although a soaking technique can work it can have detrimental effects on the contacts of the circuit board. Soaking attempts should be in no more than 1/4" of PhotoFrost Non-Toxic Cleaning Solution. The rationalization is that if it does not work the print head needed to be replaced anyway so you are no worse off than when you began.
If this is not effective replace the print head with a new one from your PhotoFrost supplier.
The Purge Unit is where the print head and carriage sit when "at rest" or not printing. It is meant to pump ink out during the printer's priming and cleaning cycles. There is also a "wiper" which removes excess ink from the bottom print nozzles. On occasion a Purge Unit can malfunction in several ways; malfunctioning pumping action can actually cause ink to reverse flow causing color cross-contamination; the wiper can fail allowing buildup of ink to dry and obstruct the outlet jet nozzles or worse, smear ink all over a picture while printing. The Purge Unit cannot be serviced by the user. It must be diagnosed and replaced by an Authorized Service Center.
Storing the Print Head: you should remove the cartridges from the head, cover the cartridge outlet holes with the orange caps and store in a zip-loc and clean the print head to store in a separate zip bag before you store it.
If you have followed all these procedures and your printer still will not function properly you can feel confident that you have done everything imaginable that a printer owner can do to get working again. Of course you can count on this happening at the worst possible time, when you have a deadline and a bunch of work that you need to print. We know - it has happened to us too. No matter how great the effort to assure quality manufacturing and performance, any machine of any price will be subject to occasional failure. We all do our very best to keep "up & running". Remember- a spare print head or back up printer is a good idea. Your business depends on it.
Here at PhotoFrost we continue testing to find solutions to any & all possible difficulties that may occur. As new procedures & solutions are developed they will be added to this knowledge base, so check back occasionally!