Preventative Maintenance for Epson 7900 for Clog Reduction

[Stan Prevost]

Hi, y'all -

I have had my Epson Stylus Pro 7900 for almost 3 years, and have had the usual clogging (or nozzle dropout) issues as others, to a degree that varies over time and not obviously correlated to anything.  The printer is lightly used.  Recently I had a worse than normal series of clogs/dropouts, and became very concerned about the possibility of having to contribute the machine to the local small landfill, so decided to do something even if it is just my best guess.  After having devoured everything I can find on the subject, including the epic LuLa thread by Eric G. (again!), I contrived and began using a preventative maintenance procedure, as follows:

1.  Inspect and clean the wiper (gentle wiping with a distilled-water-moistened foam-tip wiper if very light contamination is observed, otherwise removal and rinsing under warm water and flushing with distilled water).  I have a replacement wiper available, but the original one seems to be in pristine condition.  Always being very gentle with it.
2.  Clean the wiper cleaner, again with a moistened foam-tip wiper.
3.  Moisten the flushing box pad and the capping station pads.  I am using distilled water with 2% glycerol for a humectant.  Why 2%?  Pure arbitrary guess, didn't want it too concentrated, to avoid any kind of buildup.

I do this about once a week, printer used or not.  After starting it, I went three months without a single dropout.  I run a nozzle check before every printing session, and usually after and sometimes during.  After three months, there was one nozzle dropout on the orange nozzle check pattern, but I missed it.  Next day, there was a dropout on a different orange nozzle, which I caught, then went back and saw the dropout on the pattern from the previous day.  A single color-pair clean cleared up the problem.  In another day or three, two entire color channels dropped out.  WTF???  After several color pair cleans with only partial clearing, I did a power clean (my first ever) which restored full function.  Suggestive of an air problem?

OK, now to the current issue.  At first, when I ran this PM procedure, which is done in service mode, all was well, and when I completed a step, that step was over, and I went on to the next step, and the whole thing only took a few minutes.  BTW, I have auto nozzle checks set to OFF, and no auto cleans.  Now, when I finish the wiper cleaning step and close out the menu action (Maintenance/Wiper Exchange), The machine runs the head back to the parking position, but then enters what appears to be a cleaning sequence.  It moves the carriage back and forth, and twice goes through a sequence of five steps of carriage movement, apparently corresponding to the five color-pair nozzle plates on the head and corresponding portions of the capping station.  This takes several minutes.  When I go to the next step, using the Mechanical Adjustment/IM Gap Adjust selection to uncap the head, when done it goes through the same apparent cleaning sequence again.

I do not understand what has changed that has caused this behavior.  It seems that I have done something to trigger cleaning sequences.

Does anyone have any insight into this?

BTW, my qualitative observations would suggest that my past (and present?) clog/dropout problems correlate more to high temperature than anything else.  My room is regulated to >= 66F winter to <=77F summer.

Thanks,
Stan

[MBrew]

Hi Stan
     I too have a 7900 that requires TLC.  You say you control the temps.  Do you also control the humidity?  I have a humidifier and shoot for 40% minimum.

Mike

[Stan Prevost]

Hi, Mike.  My room is my photo room in my home, and is regulated by a zone thermostat on my heating/cooling system.  There is no humidity control, and I don't have a hygrometer.  I could say that it is expected to be more humid in the summer, but then air conditioning will moderate that.  So I really don't know.

Some people report that humidity control helps their printer, others say it doesn't matter for theirs.  I seem to have more problems in the summer. 

My issue is whether I might have done something in my PM procedures to cause these apparent cleaning cycles to occur when exiting the menu selections I use in my Procedures to access the printer parts needed.  It did not happen earlier in the time since I began the PM.   One thing that comes to mind is the AID feature that monitors ink droplets from the nozzles, to see if they are missing or deflected.  There is an AID Grid, I think on the flushing box.  If in moistening the flushing box pads, I somehow created a problem with AID......

Stan

[Stan Prevost]

Strange.  Today I went through the PM procedures with no cleaning cycles occurring, as it used to behave.

[datro]

I can confirm your observed behavior after using the IM Sensor Gap command (Un-Cap) where the head seems to go into a cleaning cycle when you click on "Cap" to bring the head back to parked position.  Just today I've been working to clear two rows of Green nozzles that will not clear with normal color pair cleaning.  I decided to moisten the five capping station pads with distilled water and park the head for a few hours to see if this will help.  I'll check it in the morning.  Whether it is actually doing a cleaning after the CAP command I'm not sure.  One thing I have noticed after doing the Un-Cap/Cap sequence several times now is that the amount of time before the head is finally parked varies; once it took only 5 seconds before parking, then another time it took at least a minute of head moving before it parked.

I have also observed that summer is the time when I have the most clogging problems.  I have kept very detailed records of all maintenance activity on my 7900 since it was put in service in December 2008.  Over the years I see a clear pattern.  For example, from January through end of May, I had ZERO clogs.  I normally print at least once or twice a week, and my studio area is maintained around 45% humidity and 68 degrees during this time.  Starting in June, I've had a clog every time I start a printing session.  And based on my past data, I expect this to continue until around Oct/Nov when we go back to little or no clogging.  In the summer, the humidity is higher (around 55-60%) and the temperature is also higher (74-78 degrees).  I am beginning to wonder if the higher temperature is a factor more so than the humidity.

[highway0691]

I have replaced the printer head of my 7900 about 18 months ago after one colour became so clogged. Yes Eric's tutorial got me there. That was done after heavy use over a 3 yr period.

Since then I've followed the rule of minimal cleaning and avoiding power cleaning at all costs, probably done it once or twice. Turn off the auto clean function.

I've also found continuous use helps, at least every 2nd to 3rd day.

The only clogs I seem to have now is when  a cart is down to around 5% and under. It doesn't always affect that cart at 5% but the one teamed up with it on the colour pair clean. For example my yellow cart is clogging but the LLK is at 3%. I know that when I replace the LLK the yellow will come good. This is an air pressure issue I believe, not so much a head problem.

Clogging is part of inkjet life and unfortunately the harder you go at cleaning cycles

[John Francis]

Printing really is the best PM...

[cybis]

Here is a list compiling some of the factors allegedly or potentially affecting the clogging habit of the Epson x900s. I'm sure of nothing except factor #1.
 

Rank	Factor	Ideal	Remark
1	Temperature	70 F	Epson recommends to keep room temperature between 59-77F. Too cold and the ink might be too viscous, too hot and the ink might dry too fast. My personnal experience over the last 4 years is that this is by far the most important factor!
3	Temperature variation in between use	as small as possible	Thermal expansion and contraction of the ink and head might create problems.
2	Multiple succesive cleaning, aggressive cleaning	Never	Multiple reports of failed heads after heavy / power cleaning
4	Humidity	50%	Epson  recommends between 40-60%.  The higher the better but molds may be an issue above 60%.
5	Dust	as little as possible	Use a dust cover!
6	Usage	print daily	Users report less clogs with higher usage. Personally, I have not noticed this. I print irregularly and I have sometimes no clogs after weeks of inactivity, and sometimes I have clogs in the middle of a stretch of heavy use.
7	Firmware	latest	Latest FW is HN0126D3 – dated 16-APR-13. Latest FWs includes improve clog prevention features.
8	Wiper blade/damper /other printer defects	No defects	See Eric's mega long post.
9	Firmware settings	default	AUTO nozzle check might keep you from printing with clogged nozzles which might damage the head. I've had good luck with the last FW.
10	Type of paper	least dusty	Some papers produce lots of fine dust: bad!
11	Time between last print and power down	as soon as possible	Printer makes different noises and potentially has a different shutdown sequence when shutting down immediately after printing vs. an hour later.
12	Leaving printer on or off	off	OFF keeps the head parked and sealed. The x900s don't seem to wake up regularly from standby to maintain the head.
13	Ink shake	?	Epson says: "Remove the new cartridge from the package, shake the ink cartridge at least 15 times horizontally in approximately 5 cm movements". Doing so regularly might introduce air but might keep the ink more homogenous.
14	Ink age	fresh ink	Potentially, old ink might clog?
15	Printer age	neither new nor old	Some reports of printer being more susceptible to clogs initially and then improving with usage until wearing off.
16	Ink quantity	not almost empty	Some reports with more clogs being associated with nearly empty cartridge.
17	Is printer level	yes	Epson recommends making sure the printer is level. Presumably this makes some sort of difference. (level from left to right and back to front)
18	printer hardware revision	?	Are there different hardware revisions?
19	Max temperature ink cartridge was exposed to.	< 40C	Epson recommends to store ink cartridge below 40C. Presumably, something bad happens at high temperature. Shipping ink in the summer in the Southwest will definitely expose those inks to higher temperature than that.
20	Printing with clogged nozzles	NO	Does printing with clogged nozzle damage the head?
21	startup cartridge	NO	Some reports of more clogs occurring with startup cartridges.
22	Cartridge design revision	Newer	Is there an old and a new cartridge design?
23	Phase of the moon	not full	Obviously!

[Benny Profane]

Thanks for that list.