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Author Topic: Epson 7900 from the inside - out  (Read 1092813 times)

Blue moon

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Re: Epson 7900 from the inside - out
« Reply #1080 on: January 03, 2013, 08:32:23 am »

For got that its one composite product which does not allow variations in its make up...hopefully it does the trick as it is ..
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Larry Heath

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Re: Epson 7900 from the inside - out
« Reply #1081 on: January 04, 2013, 03:45:09 am »

I wonder how effective a 1 to 1 or even neat Photo Flow might work as a puddle cleaning agent? As opposed to the more typical water or Windex Classic type cleaners? With the glycols it would likely have a better retention time around the print head as opposed to the others. How about say a 70/30 mix of Photo Flow and Windex?  I wonder if the addition of the polar cleaning agent in the form of the ammonium would help or hinder? Given that Windex has always worked for me in the past as an effective puddle cleaner.

I have a couple of old Pro 4000 ‘s that have been getting harder and harder to get and keep clean; I think next time I am going to try a puddle clean of Photo Flow instead of Classic Windex and see if that cleans better or quicker. Also I have some old carts around that I think I may repurpose and fill with a 1 to 1 of water and Photo Flow and do a few power cleanings and see what happens.

Anyway there is some more food for thought.

Later Larry
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Erik Ulstad

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Re: Epson 7900 from the inside - out
« Reply #1082 on: January 04, 2013, 12:24:38 pm »

Hello there-

I own an Epson 9600 and have two rough clogs.  I came across this forum a month or so ago and gained lucidity on my problem when I read about the wiper crud re-entering print head. Here is the current solution I am in the process of prototyping, for whatever it's worth:

I live in the mountains, in a dry climate. My humidity is about 20% daily, in the winter. I noticed the topic of a micro climate, which I am in the process of simulating. My office is very small, 10' x 10' so I'm trying a humidifier right now.

Here is what I'm looking at embracing for a solution.  It's a little robust, but what the hell.

There seem to be two opportunities for solutions.  One is the wiper blade, the other is clog prevention.  I feel that if you can completely bypass the wiper blade you are setting yourself up for success. I also feel that if you can keep something moving through the print head while the print head is not in use (perhaps dial in the cleaning solution that has been mentioned here before) then you are creating a situation where there is a low probability for a clog to form inside the nozzle.

My attempt is going to look like this:

1) remove the wiper blade and replace this "action" or "concept" by using, and disposing of after use, chamois cloth.  By design, a wiper blade doesnt seem to come close to the "solution" of cleaning the excess ink off the print head after a head clean.  Paper towels were never designed specifically for this job, but have assumed the role (clear flaw here is paper bits or dust left engrained in print head). On the other hand, chamois cloth is much more expensive, but worth it for this stage of the solution process, as a means. Chamois cloth is designed to clean fine surfaces and cutting up the cloth into smaller pieces,  and giving the print head a careful "shoe shine" is what I have in mind.  

2) remove the clog itself. This seems to be the million dollar question in some ways. Ill share a little concept that has been on my bandwidth and see what surfaces.  

I make kombucha and bottle it in wine bottles.  Instead of using a proper cork, I use "tasting corks" which have a cap on the top of them to assist in removing the cork. A few times I've gone to uncork the wine bottle to drink my kombucha and have encountered the cork "stuck". A few times, without thinking, I applied a forceful twist and ripped the cap off the cork. Not a huge deal, I get a wine opener and open the bottle. In not wanting to waste my tasting corks, I took a look at the bottle and realized that I had been storing these bottles as they would sit on a table.  In doing so there is no moisture on the cork itself, and the cork dries out (you wine drinkers will know that wine bottles that have real corks, not plastic corks, are stored at an angle so the wine touches the cork) . I then started to tip the bottles upside down for as little as 15-30 seconds and wet the cork before opening the bottle.  I got good results.  

Here is where the clog comes into play.

I removed my print head and cleaned it with a solution I found online.  This was the first time I went this far down the rabbit hole with repair. I got improved results but the stubborn clogs still persist. I've since removed the the dampers from the ink lines a couple times and the dampers from the print head a couple times. In doing so, I realized this wasn't that hard to do.  A little messy occasionally but put on rubber gloves and get some q-tips soaked in windex for cleanup.

What I'm looking at doing (to get the stubborn clogs removed) is apply motion (slight pressure) on both ends of the clog, at different times but in close duration.  This is a bit of a lofty goal but from all the posts out there with nozzle clogs, it needs to be.  15 seconds of light pressure from the end where the ink line inserts, 5 seconds of pressure from the other side.  I am not sure if the nozzle is a "one way" flow as previously touched on in this thread.  Even if it is, the flow coming back into the print head would be far less than what is flowing out, per traditional travel of ink. I'm going to begin not using any pressure at all, just puddling, then move on to slight pressure if need be.

 The visual in my mind is this...when a wine cork is in a bottle there are small spaces in between the cork and the glass where liquid can touch. When my liquid (kombucha) touches this area, I get the desired result of the cork releasing.  Now picture this (this is what is in my mind). Instead of visualizing a "piezeo tube" I picture a set of Chinese finger cuffs (for some reason this came to mind when I was thinking about the flexibility of the piezeo nozzle).  The finger cuffs have a cork stuck in the middle.  Now picture liquid accessing each side of the cork. So that means that the finger cuffs are flexible in a small way and likely allow a bit of an improved space (between the cork and "glass" or cork and finger cuff) for the liquid to access each time liquid is applied to either side of the cork. And it's a very, very small improved space but likely gradually improved each time liquid hits it, even if in tiny amounts. The rate and duration of liquid coming in contact with both sides of the clog is what will allow the clog to dissipate. Yes, this may mean that a print head will need to be connected to a setup like this for a couple weeks (months) perhaps, but our boy Eric has been after it for close to a year. In hindsight 2 weeks is nothing.  I've been trouble shooting for two months and am front row and center with "necessity is the mother of invention."

My idea is to take the print head out of the printer and connect latex tubing, the same size as the ink tubing, to the print head (7 tubes, 7 colors on the print head).  I then gently pump (I'm thinking breast pump) cleaning solution through the print head. And I do mean gently (I recall someone posting something about the metric used for pressure? A BAT perhaps? Long term we dial in the correct BAT that sends pressure but doesn't throttle the print head). On the other side, the clog itself needs to be in motion or closer to being in motion. So I then puddle cleaning solution on the top of the print head and access the areas I was referring to before (the space between the cork and glass) on the business end (the side of the print head that faces the paper) of the clog. Perhaps apply a bit (a tiny bit) of pressure somehow to this side as well.  Desired "action" is cleaning solution gaining access to the space in between the clog and the piezeo wall as often as possible, but not at the same time.

This concept isn't new at all.  Often times we get out the ol' syringe and plastic tubing and try to work it out that way.  I've found that rather challenging, mostly because the syringe doesn't move smoothly. In fact the one I have is quite jerky, which is dangerous to the print head if you should happen to "burst" fluid through the syringe. The other problem is the the tubing (female end) rarely matches the male end where the traditional ink tubing fits. The tubing is usually too small. How about a piece of latex tubing that fits snugly?

While this is a subtle attempt the long term solution would be a pump with an auxiliary set of nozzles attached to the print head that gently (like 3ml a day gently) pumps a cleaning solution through the print head while the printer isn't in use.

Cost:
The pump (I'm looking at using a breast pump because of the "gentle" pressure associated with such a device...it will be tested of course. Long term perhaps we stumble on the right brand name breast pump that offers the correct pressure). If we stumble on the right pump it's likely $50-$400.
The rubber latex tubing (3 bucks a foot?)
Tubing assembly (not exactly necessary but could be convenient)
7-way splitter for tubes coming off pump
Adaptor from pump to tubes
Towel on the back end of the print head to absorb the 3ml per day that comes out of the print head
(more costs associated with a device on the print end of the print head that could gently feed a solution down the "wrong way" of the print head....much more long term)

This would primarily be a tool of prevention but would also serve as a remedy if need be. I heard somewhere that an ounce of prevention is worth something valuable.

Eric, well played sir.  To all the other who have contributed to this point, thank you for being a part of this solution.  

I keep looking over at my copy of "The Cluetrain Manifesto" and smiling.

I'm not a handyman or a technician or a scientist or a even an amateur printer.  I'm a ski bum in Colorado who wants to print stuff.

Again, for what it's worth.

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sfblue

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Re: Epson 7900 from the inside - out
« Reply #1083 on: January 04, 2013, 03:25:07 pm »

Re: humidity

I used to live in NY and had to use these for my musical instruments during the winter:
http://www.dampits.com/
Wooden string instruments are really fragile- can't get them wet at all but low humidity over time causes problems. 

Rather than humidifying a whole room constantly, you might be able to make something similar, or use several of these dampits with a cover over the printer.  There are other companies that make similar products for instruments besides the damnpit. 

I know that it is a very different kind of situation in that with an instrument you have a closed case, but maybe some solution like this with a covered printer might help from a humidity standpoint?  Just a thought . .
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Eric Gulbransen

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Re: Epson 7900 from the inside - out
« Reply #1084 on: January 05, 2013, 01:54:38 am »

SO CLOSE I CAN SMELL IT....


Last night I warmed Alan's original solution up and drew it back up through the head from the face - rearward, by gently sucking from a syringe separated from the head by about twenty inches of clear tube.  This way I figured negative air pressure would be a buffer if the solution needed more time to get through the head's internals.  For what it's worth warm solution pulls through the head easier than cold solution.  Someone tell me why, please, I need another headache right now.

After all channels got about 10ml of solution run through them I re-visited the Green channel on this particular head - which went terminal many moons ago.  I did a few runs on the green channel.  In the end I ran about 40ml of solution through it, gently.  Then I let the head, with solution still in it, sit tight until this evening when I installed it.  I didn't have my genius with me (cause he's got a girl now) so I put the 9900 back together solo.  I doubt I missed anything.  Machine started up fine, recognized everything fine, tried running a cleaning cycle, got through a lot of it, then flashed me an error message - 131B. 

I looked this code up, it means "They get too close now, tell them turn machine off - call service.."

Bastids

I'm shot right now, been powering through an illness that's trying to get the best of me all week.  This was my last goal for the week, testing the head.  This error code stole my wind.  It's second meaning is " Head driver (transmission gate) overheat error ".  I'm not sure because I have put no thought or effort into diagnostics yet.  Haven't even checked the service manual.  Least it didn't flash me "Fatal error/replace head."  ..who knows maybe that's next.

I swear I'm gonna beat this machine if I have to do it with my framing hammer.  Either way it's gonna get done.

chaddro

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Re: Epson 7900 from the inside - out
« Reply #1085 on: January 05, 2013, 10:23:28 am »

Hey Eric,

I looked up the error code in the field repair guide: 13xx Ink Cover Error

You may just need to check the ribbon cables.

131B Thermistor Sensor Error: The Thermistor on the Print Head Driver reports an over temperature condition

Remedy:

1. Re-seat the Print Head Cables on the Main Board side.
2. Re-seat the Print Head Cables on the Print Head side.
3. Replace the Main Board.
4. Replace the Print Head.

When D1 was out to replace my machines guts (AID board, pump cap, mother board) the tech said you can kill a print head and/or motherboard by improperly inserting the ribbon cables.
Of course, this was as he put the wrong mother board for my machine in the beast (he didn't check the board first). It was actually kind of funny in a morbid way. He's all chatty as he's reassembling
the machine (I was drilling him with questions), and grabs a ribbon cable to insert into the board ... and there's no socket for it ... cartoon moment with the question mark over the head - priceless!

I was wondering what you thought of making a "dedicated" cleaning station using an old pump cap in it's own rig. Is there a way to measure the maximum suction force the
pump cap generates? It would be nice to know if your in safety limits when drawing cleaning liquid through the head. But it must be "safe" to do if that is all the pump cap does.

I can't image a tiny aquarium pump generating much force, but who knows.

But, as you said recently, watching the pump cap suck ink out of the head is enlightening at how much it sucks out!

BTW, every time you mention the "oh canada" head I get that cringe in my gut for suggesting it. Seeing the actual blown ink channels makes me think dude took no care (or his own website's advice) about the maximum force that the head could handle. Futz.
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Eric Gulbransen

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Re: Epson 7900 from the inside - out
« Reply #1086 on: January 05, 2013, 12:59:40 pm »

Thanks Chaddro.  You are truly the information mercenary.  Batteries charged, ready for battle.  I'll tear it apart after lunch.  I hope I didn't fry anything but if I did let's look at the bright side - I will finally have learned to cook.

Eric Gulbransen

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Re: Epson 7900 from the inside - out
« Reply #1087 on: January 05, 2013, 04:19:13 pm »

We are officially up and running.  It was indeed a crooked ribbon cable at the printhead.  That's what I get for operating heavy equipment under the influence of illness. 

Machine fires up fine now, has a healthy appetite for ink (which means the fever has passed, it's acting normal again), and it actually prints.  Here's the thing though, it's pretty well starved for ink - most of the channels (including our suspect green) aren't producing much yet.  My initial hopes for this first cleaning test were that we could create a difference with our cleanings.  Any difference.  That hope of course was recently reduced to "I'd be happy if this head is still recognized as a printhead by the printer."

So our reduced hope has indeed been satisfied.  We damaged nothing, at least as far as I can tell.  As for whether or not we get all channels 100% firing again, we will know that soon.  I have to go buy more ink first... 

classic 


My gut though says we will not have cleared the piezoelectrics of dried ink.  I have a few dried channels here which have been removed from their heads.  I have been soaking them along with our in-tact heads.  Everything I have done to the printhead, I have done to these open channels.  The crap news is these open channels have not been cleared by our first-run, mild solution.  This is why I expect our 9900 head will still be clogged once I'm done flushing money down the maintenance cart (toilet).


so, good news and same news.  At least we now know that we can indeed successfully remove a head, soak a head, flush a head, re-install a head, and then print.

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Blue moon

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Re: Epson 7900 from the inside - out
« Reply #1088 on: January 05, 2013, 10:30:02 pm »



Machine fires up fine now, has a healthy appetite for ink (which means the fever has passed, it's acting normal again), and it actually prints.  Here's the thing though, it's pretty well starved for ink - most of the channels (including our suspect green) aren't producing much yet. 
Eric
Sympathise with you firing ink into tank...its gut wrenching stuff...
If it helps at all....the following was my experience with dumping good ink...
i could not get any color after restarting a machine that was 2 years idle in Piezo Flush storage fluid...as an economy measure i dumped paper pads that were in the maintenance tank and replaced with handy sized ice cube block that fitted nicely into the emptied tank and means i recycle the tank and ink and  far more important ,I see the clean liquid (or ink depending)clear as daylight coming out of the park station  and falling into the tank..anyway ...the point is i got practically no ink landing on paper until i did a power flush...the result of the power flush was a mass of air bubbles lying on the top of the power flushed ink (recycled pink cleaning fluid actually ) in the remodelled maintenance tank...imo ..it would have taken years of regular printing to get that air out...after that i got a much improved print pattern ...there is no air at all to be seen in the maintenance tank  ...just my three regular clogs on paper..
Good luck with the clog stalk...i'd hate to be that clog when you come popping round the corner...its gonna turn green in the face...
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Eric Gulbransen

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Re: Epson 7900 from the inside - out
« Reply #1089 on: January 06, 2013, 01:53:27 am »

All channels clear and shooting healthy again.  Didn't take as much (money) ink as I feared.  

....but (come on you KNEW there would be a "but") green is still out to lunch.

What was my original goal here in this first cleaning test - to create a difference?  Any difference?  Well we accomplished that - green is worse now.  Used to have two lines up top and two down at the bottom of nozzle patterns.  Now it just has one line at the bottom.  

Does this depress me you ask?  Am I defeated you wonder?  Will we press on regardless?  Oh how the hell do I know, I see about nine feet in front of me at all times.  Never farther for fear I'd stop right here.


I notice, and tell me if you think I am crazy, that unclearable clogs seem to come in groups.  More than that they seem to grow, like viruses sometimes.  And rarely from different areas of a channel.  Instead they usually grow outward, from one area.  This observation, which I am again observing on this green clog cluster, seems to have potential support of a theory that's been brewing in the back of what's left of my brain.  If chamber walls flex to fire nozzles, and only one wall separates each chamber, then it is more than likely that dried ink inside one chamber will have a limiting affect on how well it's neighboring chamber fires.  

Makes sense right?


We need now more than ever to find/test more effective cleaning solutions.  Like I said my open clogged test channel is unaffected by our rubbing alcohol/distilled water/Dawn concoction.  Now neither is our test head.  I think the operative word to focus on next is Larry Heath's "surfactant".  Right now that word sounds sexy to me
« Last Edit: January 06, 2013, 01:57:29 am by Eric Gulbransen »
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Luca Ragogna

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Re: Epson 7900 from the inside - out
« Reply #1090 on: January 06, 2013, 11:22:09 am »

It took several days to skim through this post and I'd like to say thanks to Eric and everyone else that has been experimenting, researching and theorizing about what goes on in these printers.

I have a 9890 with a nasty clog in the yellow channel, and I'm about to get started on trying to clear that up. Wish me luck.

I didn't read every post because there's just so many, so forgive me if someone already posted this idea.

I'm posting about the Holiday Mode idea. If it's basically to make sure that the printer prints something everyday then I have a bit of a solution for Mac users. It's far from perfect but *might* do the trick. Using Automator you can make an application to print a page and then schedule it in iCal to happen every day. I've attached a sample of what I'm talking about. The automator action picks a specified file and then sends it to the printer. Very simple but it'll take some tweaking to work for you.

Open the "Holiday Mode.app" application that I've attached by dragging it on to automator and in the "get specified finder items" box click the "X900_routine_print.jpg" item and click "remove" (I put it in there as a place holder). Now click "add" and find a file that you want to use to print every day. I'm going to use an 8x10 test page with all the colour ramps and such (8x10 because the system assumes you have letter sized paper loaded).

In the "Print Images" box pick your printer from the drop down. Save and close.

Open iCal (Calendar), make a new event, double click on it and click "edit". Set the time you want the print to happen and set repeat to "every day". Click on alert, select "Open File" - you'll get a few more options, the default file to open is iCal. Open the pull-down, pick "other" and find the automator action.

Now you'll have a test page print every day at the specified time as long as your printer is on with paper loaded. It will not print patches of pure ink but with a decent test page it should fire enough ink through the heads to keep everything moving.

Cheers!

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Eric Gulbransen

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Re: Epson 7900 from the inside - out
« Reply #1091 on: January 06, 2013, 12:12:24 pm »

Nice work Luca.  Automator is one of many programs on my mac that I still don't grasp.  Thanks for this homework you've done. 

Here is something to consider - when you remove your printhead with the intent to experiment with clearing unclearable clogs, it's highly likely it'll be off the machine for some time.  This poses two extra (like there aren't enough already) challenges.  One, your head is even more susceptible to drying out once off the machine.  Two, so are your dampers.  I haven't talked about this because until we find a way to clear unclearable clogs why even suggest trying.  But since you're about to charge forward on your own quest I suggest you have a system in place to plug the dampers while the head is off the machine.  This will keep ink from draining out of the unit, and keep it from drying out.  We used dowels carefully slid into the damper fittings that the nipples of the head itself slides into.  Unfortunately ours were wood, which I would not use again as it absorbs the ink and seems to dry itself onto the rubber grommets of the dampers.  I will look for plastic, or rubber plugs to replace the dowels next time.  ...But I'm chasing down different chemicals first.

Mark D Segal

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Re: Epson 7900 from the inside - out
« Reply #1092 on: January 06, 2013, 02:47:56 pm »


I'm posting about the Holiday Mode idea.


Luca, thanks ever so much for doing this. I've downloaded it and made a PDF of your instructions in the referenced post. I shall have to make some time to play with it, as my life has been involving longish periods of absence from my printer (4900) and every time I come back to it, a good 45 minutes and a number of clean-print-clean-print cycles are needed to restore it to 100% - which it always does, but what a nuisance. The question then is whether your routine or my periodic regeneration routine will be the more cost-effective approach. The one qualm I have about any "holiday mode" is the need to leave both the computer and the printer on for weeks at a time with such intermittent use. I don't know whether it's an issue for either machine - as at least in the case of Epson the advice has always been to shut the machine off when not in use, to insure that the head is properly parked and sealed.
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Eric Gulbransen

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Re: Epson 7900 from the inside - out
« Reply #1093 on: January 06, 2013, 03:15:27 pm »

I agree on the automotor idea Mark.  Good promise, just a few kinks to work out.  For me one would be roll paper rather than single sheets, for you that's not a problem. 


This morning I began experimenting with the cleaning solution HAL sent me months ago.  Again, this fluid came with no instructions other than "be careful, I have no idea what it does - rare few do".  So until now I have left it in the box it arrived in.  There are two fluids, one deep red the other clear.  From what I can tell after watching the two fluids sit on top of a clogged channel, the clear is most likely a rinse - not much goes on under the scope.  The red however is a different experience.  The channel I chose has been out in open air, without it's top, for weeks.  It is saturated with cyan ink, completely dried and hard.  The chambers are all locked solid with cyan ink, filled to the top.  After a good fifteen minutes with the red cleaning solution sitting on top of this channel, the red puddle turned purple - a good sign.  By the half hour mark, under the greatest magnification that this scope has (280x - which basically shows only eight chambers at once it's so zoomed in), it's a fascinating view.  It's like watching a video taken in low light, with the gain amped up.  What in the video would be digital color noise, is on the channel (I expect) the red cleaning solution working away at the dried cyan ink, on a microscopic level that I do not have the ability to fully see.  This movement is so tiny I have to ask myself if I am imagining it.  I am not.  To put a size reference together for you, imagine in my channel chamber speed bump illustration, a thousand or so tiny speckles of red and blue sparkles flashing between the narrowest passage of the speed bump and the opposing chamber wall.  Tiny stuff.. 

After a few drops of the clear solution wash the red away, the chamber wall tops are revealed.  They are square, sharp edged, immaculately clean, and full of hope that the rest of the chamber walls just below could possibly look the same with more time soaking.  Very interesting. 

Right now I have a free channel lying face down in a tiny puddle of the red fluid, inside a sealed Tupperware container.  I plan to let this soak for 24hrs.  This should be long enough to see if the clogs are at all clearer, and if the channel is at all damaged.  Interesting times lay just ahead.

Mark D Segal

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Re: Epson 7900 from the inside - out
« Reply #1094 on: January 06, 2013, 03:19:53 pm »

I agree on the automotor idea Mark.  Good promise, just a few kinks to work out.  For me one would be roll paper rather than single sheets, for you that's not a problem. 


Good that you mentioned the roll-holder - actually for me it's an opportunity, because the 4900 does have a built-in roll-holder, which I can imagine being more reliable to let the machine auto-manage compared with a tray-fed mechanism. The roll is a straight pass-through, while in the tray the paper needs to be pulled from the tray and turned for printing.
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Larry Heath

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Re: Epson 7900 from the inside - out
« Reply #1095 on: January 06, 2013, 05:55:47 pm »

Discovery number 2:

About mid-way through this journey I sent our Epson Stylus Pro 7900 printhead to Canada, after me and my genius buddy decided we could do no more to help clear it on our own.  Once in Canada our head was subject to both an ultrasonic cleaning, and also a flushing.  When we got the head back into our 7900, all it produced were fatal error messages.  Our goose (printhead) was cooked.

In the many months since experiencing this disaster, I have done a lot more learning - thanks in great part to other (more intelligent/better educated/and vastly more experienced) users right here on Luminous Landscape.  I have also done a lot more thinking.  And, finally, I have done quite a lot of poking around INSIDE the very printheads which we have all grown to enjoy a love (beautiful prints) hate (ink-time-money-printer-destroying-clogs) relationship with.  While I do still have hope that we can find a cure for X900 clogs, for quite some time now I have quietly hidden my greatest fear - that terminal clogs are not clogs at all.  After all, the wonderful world of Piezoelectrics is not only amazingly tiny, but it is also amazingly fragile.  For sure with all of the aggressive Power Cleanings we are forced to resort to in order to combat the most tenacious clogs; the sucking, the smearing, the pressures of ink being forced through the printhead's internals - it is quite possible that we all walk a fine line between helping our printheads with cleanings, and hurting our printheads with cleanings.  So for quite some time my greatest fear has been a discovery that terminal clogs are actually damaged Piezoelectrics, rather than simply clogs.  

Since this very point is such a vital element of our journey, late last night I finally gathered the courage to act on finding our answer.  I performed an autopsy on our "Oh Canada" X900 Printhead.  Remember, before we shipped it to Canada it simply had un-clearable clogs.  It returned with "terminal errors".  While this is a tragedy, it is also an opportunity.  If the piezoelectrics in this Oh Canada head are damaged, well then here would be our answer - damaged piezos = fatal errors, dropouts = clogs.    Anyone else curious what I found?

It WAS too much fluid pressure that killed our Oh Canada head.  I feel confident in this assessment due to the fact that both channel pairs show damage exactly at the source of where the pressurized fluid would have entered from - which is the same place where ink enters from.  Take a look for yourself.  








Eric, a suggestion, while your current working microscopy setup seems to work pretty well, this cheap little jewel, or ones like it, linked below works quite well. It does still and video imaging direct to computer. For $40 or $50 it might make life a bit easier, simply attach to the camera tube of your scope. I’ve done some photomicrographs at the 1000x to 2000x level that are quite serviceable. The thing has its own variable internal light source as well, so you could even possible use it without the scope up to about 400x. It also comes with software and standards so that you can directly measure the size of objects in the field of view.

I can see one bump and its 20 minutes of fussing around to get things all lined up again with your setup.

http://www.buy.com/prod/new-version-400x-usb-digital-microscope-video-camera-best-choice-of/222931099.html?listingId=147632864

Just a thought.

Later Larry

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Blue moon

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Re: Epson 7900 from the inside - out
« Reply #1096 on: January 06, 2013, 08:01:42 pm »

At last finished the glycol/glycerol power cleaning program with Epsons service solution and Inkjetmall Piezo Flush.Still have the same 3 jets clogged...
made no difference warming up the glycol as it entered the head...hoped that it might..
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Eric Gulbransen

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Re: Epson 7900 from the inside - out
« Reply #1097 on: January 06, 2013, 08:25:17 pm »

At last finished the glycol/glycerol power cleaning program with Epsons service solution and Inkjetmall Piezo Flush.Still have the same 3 jets clogged...
made no difference warming up the glycol as it entered the head...hoped that it might..

tenacious bastids aren't they...



Thanks for the tip Larry.  I actually have a camera mount for this scope which does make life a LOT easier, but the optics are not so great.  I've never seen this device you linked to.  Wish I had about a month ago, could have saved me a small bundle.  I think?

chaddro

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Re: Epson 7900 from the inside - out
« Reply #1098 on: January 06, 2013, 08:31:34 pm »

Luca, thanks ever so much for doing this. I've downloaded it and made a PDF of your instructions in the referenced post. I shall have to make some time to play with it, as my life has been involving longish periods of absence from my printer (4900) and every time I come back to it, a good 45 minutes and a number of clean-print-clean-print cycles are needed to restore it to 100% - which it always does, but what a nuisance. The question then is whether your routine or my periodic regeneration routine will be the more cost-effective approach. The one qualm I have about any "holiday mode" is the need to leave both the computer and the printer on for weeks at a time with such intermittent use. I don't know whether it's an issue for either machine - as at least in the case of Epson the advice has always been to shut the machine off when not in use, to insure that the head is properly parked and sealed.

Hi Mark!

When D1 was out to work on my machine (9890), I again asked about this ON/OFF question. He said that when ever the machine is not actually printing or performing some kind of maintenance (cleaning, AID check, etc), that the head always returns to the capping station and is fully seated.

My 9890 is 1-1/2 years old now. I rarely ever turn it off. I can say that it's easily been on for months at a time. Personally, I think it's better to leave the printer on. This way pressure is maintain in the ink carts, and the lines, dampers and ink TO the head should NOT allow air to pull back into the system (a notorious problem with my 4000).

BTW, take a look at this post for how to schedule your machine to automatically power up. You could then run the holiday script, and then power down:

http://www.macgasm.net/2010/03/25/mac-os-x-tip-automatic-power-onoff-with-os-x/

« Last Edit: January 06, 2013, 09:12:28 pm by chaddro »
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Mark D Segal

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Re: Epson 7900 from the inside - out
« Reply #1099 on: January 06, 2013, 08:45:55 pm »

Thanks chaddro.
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Mark D Segal (formerly MarkDS)
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