New yellow head, not drawing ink.

[Warped&Proud]

Hi,

In my ongoing effort to let our JV3-250SP drive me insane, we are having yet even more issues.

At first it was just the yellow head, giving off a bit of a yellow halo around everything with Y in the CMYK mix. Then the behavior spread to other heads, most notably Cyan at the moment. Because the yellow head was the worst culprit, and because it was dropping out completely this morning dispite syringing and swapping dampers, I swapped it out for a new head (even though it was only about 6 months old).

Now, the new head won't produce a test drop. I've swapped heads before and usually they would produce something in a test drop afer a couple ink fills and a normal cleaning or two.

Other interesting bits of note:

The forward rotary pumps that draw waste cleaning ink from the capping station does not seem to cycle much (if any) ink through the tubes that run through them. That is odd to me as I remember seeing a regular streem of ink bubbles the last time I watched it work - and when I run the same procedure on our JV4s.

The capping station looks like it seets correctly against the heads durring cleaning and ink fill prodecured.

The ink lines TO the heads are clear of air bubbles.

Anyone have any other ideas?

And can anyone give me a part number/ID for the ribbon cables that go from the slider board to the print heads?

As always, thanks in advance.

 

[APC Tech NE]

Did you thoroughly clean the carriage plate before installing the head? Sometimes ink buildup will cause the head to sit higher in the carriage interrupting the seal with the cap. Also, make sure the screws holding the head are tight, sometimes they can be deceiving, they will feel tight, but the head is actually loose. Put a syringe on the cap side of the pump and draw, if you hear an air sucking sound you have a capping problem. If not you should be able to prime the head in this manner.

 

[APC Tech NE]

Cables are: E102218 head FPC assy

 

[Warped&Proud]

Thanks for the cable ID's.

We keep our gear *clean*. We run water based dye-sub inks for transfer onto fabric. The stuff cleans up nearly perfectly with isopropyl. I swabbed the bay out before dropping the new head into place.

I have confirmed that there is a capping problem. I do get air when I syringe from the cap side of the pump. I've also visually confirmed that the head sits slightly slanted, sloped to the front.

The head is completely screwed into place. I lostened the front screw and tried to "wiggle" the head, but it is solid in-place.

One more detail to throw a kink into the mix:
There are four tiny red LEDs on the main board, one for each head.
Three are lit, one each for Black, Magenta and Cyan heads - but not for the yellow head.

As a result, I retested the seating of the two ribbon cables from the slider board to the head. I also swapped them for another set known to be good.

Same results, nothing at all from the yellow head and the LED on the main board still does not light up.

 

[Modern Ink]

Then the behavior spread to other heads, most notably Cyan at the moment........

Other interesting bits of note:

The forward rotary pumps that draw waste cleaning ink from the capping station does not seem to cycle much (if any) ink through the tubes that run through them. That is odd to me as I remember seeing a regular streem of ink bubbles the last time I watched it work - and when I run the same procedure on our JV4s.

Sounds to me like it is the pump. The Yellow and Cyan run on the same pump

 

[Warped&Proud]

It really does feel like this machine has parts failing left & right...

 

[jdigital]

Might need a new slider board. I have replaced heads before and it has damaged the slider board. Did you power down the machine and unplug it B4 you installed the head. It was recommended by a mimaki tech to do this before replacing a head. If it's not unplugged it could cause a short and fry the head or slider board.

just some input from JV3 experience

 

[Warped&Proud]

Some people might not think twice about replacing parts on an electronic device while it is hot. I won't. I've seen too many machines die spectacularly that way.

No, I always power down the machine as soon as I need to touch anything electronic.

Oh, and the slider board was replaced a little over a year ago - it should be fine.

So, we have suggested the following:
* Pump
* Slider board
* Main PCB (from another source)
* capping station

Things that have been done so far:
* Replace the dampers on the yellow head
* Syringe the head from the capping station
* Replace the ribbon cables to the yellow head
* Replace the yellow head
* Syringe the lines (just to make the ink actually move and then to bleed out a couple air bubbles that resulted from the ink crawling back up the line).

Net result -- yesterday the yellow head was not working *AT ALL* by EOD. I set it an over-night nozzle wash and this morning it is now working ... Sometimes.

Now time for some testing to see if it is really working and get the slignment squared away.

 

[Neil]

I have confirmed that there is a capping problem. I do get air when I syringe from the cap side of the pump. I've also visually confirmed that the head sits slightly slanted, sloped to the front.

The head is completely screwed into place. I lostened the front screw and tried to "wiggle" the head, but it is solid in-place.

My bet is the head isn't seated properly.
You may think it is but it's easy to get wrong.
It can feel like it's clicked in place and you can screw it down but it can still be out.

In your case it sounds like it's sitting up at one end and unable to get a seal around the cap.

You may be able to manually press the cap up against the head while doing a clean to confirm this.
If it starts drawing ink, then you know the problem is that the cap was not reaching the head properly.

Take out the head and re-seat it.

 

[Graphics2u]

I've also visually confirmed that the head sits slightly slanted, sloped to the front.

If the head is not straight like the others that is not correct. I'd take it out completely and reseat it. Not sure how the mimaki's are but my Mutoh uses that same head and there is an adaptor plate on the bottom that could be misaligned.

 

[Warped&Proud]

Thanks everyone for the advice and assistence.

We have had nothing but problems with this machine over the last month.

The hight of both the capping station and print head caddy has been adjusted and leveled. The individual heads have been pulled out, adjusted and reseated. In every single case, once we get a problem head working again, another decides to start dropping out.

We even pulled out the new bulk ink carts and put the old ones back in - thinking it was a pressure issue. That helped immensly, but now we are dripping all over the place. It also fixed the yellow head - more or less (still mists slightly, but not nearly as bad).

That brings us to our current bad heads - Cyan and, to a lesser degree, Magenta.

In each capping station seat (I don't know what it's really called), there is a small perforated metal plate. The one for Cyan is missing. We did have it, but it is currently being used by the black station as it seems to help prevent the black head from dripping for whatever reason. Funny thing is, before we swapped that tiny metal plate over to the black capping station seat, I don't ever remember seeing one in that location.

Can anybody give me a part ID or number? More importantly, can anybody suppest where I can get one for cheap?

 

[SE SignSupply]

Never seen just the metal plate, we always buy the entire cap top.

I have them in-stock for $53.64 each.

Ryan

 

[Warped&Proud]

I found the little metal plates. They are Mimaki part # M508337. The Color Zoo out of Vegas has them for $10 each. Ouch.

I have some nickle sheet kicking around - maybe I could make one as a placeholder.

 

[APC Tech NE]

The purpose of the plate is to keep the heads from drawing waste ink back into the heads while capped. Sometimes called "cross contamination". Make sure you place the bumps down. You may not have lost it, I end up finding these under the pumps or wiper assembly. Are there any independent technicians in your area that can help you out? I work out of the Boston area, so the travel expense would be on the high side.

 

[Warped&Proud]

Thanks for the info on the placement and purpose of the plate - that was something I was about to ask.

I'm looking into local techs, but the boss has recuiled in horror at the request. The last tech that came out a year ago was from Vegas and I've had little luck in finding a local guy.

We've made progress on getting things working, Yellow is working well while black not so much. Only Magenta and Cyan are conssistantly failing. We are soaking and will draw solution through the heads to see if that works. They might just be clogged due to innactivity.

I also have a more targeted question that requires a new thread.

 

[Warped&Proud]

The never-ending battle continues...

The ribbon cbles from the slider board have been replaced a week ago due to a couple of the old ones delaminating at the contacts.

Today, none of the heads will drop ink. That's after spending most of yesterday disconnecting each one, soaking in solution and drawing solvent through them. Usually this works, but not this time.

It as doing so well - they were starting to come back late last week after plugging some new dampers in.

We've swapped dampers, bleed the lines of air, adjusting capping station/head caddy height, performed ink-fills, cleanings, etc. We can draw some ink through the capping station (visually confirmed in the top of the capping station), but otherwise nothing works.

Again, some of the heads are NEW and still won't lay ink onto paper...

The printer is in an environment where the temp & humidity is uncontrolled. We are currently going through a record-breaking heat wave in Seattle. Would these conditions affect the machine so much it would not lay down even a single drop of ink in a test draw? I expect it to drop out durring drinting with these conditions, but nothing in a test drop? Come on... Where's the humanity?!?!

Morbid joke: Someone, please just kill me now and get it over with...

Serious: Anybody know any good Mimaki techs in the Seattle area? PM me, please...

 

[Samurai_Screwdriver]

I expect it to drop out during printing with these conditions, but nothing in a test drop? Come on... Where's the humanity?!?!

Uh oh. You're not going to like this... Usually (i.e. 9.9 times out of 10) not getting a single drop of ink from any of the Heads indicates an electrical problem I would disconnect all your cables again and scrutinize them for any shorted contacts/damage/burn-marks.

I hate to be a merchant of doom but it's quite possible that you may have a dud Mainboard on your hands now. You might want to try booting up the printer with no Heads attached - If it comes online without throwing an error (It should throw an "Error 07") then you've almost certainly got a cooked Mainboard.

I'll ask around and see if I can get a recommendation for someone in the Seattle area.

 

[Warped&Proud]

Hey, thanks again Dave.

You are not so much a merchant of doom, but more like a voice of reason. You are pointing in a dirrection we thought we should look at next anyway.

Besides, my expectations with this thing are so low, all I can do is look up. Which brings me to good news...

Based on your suggestion, we disconnected all the small ribbon cables connected from the slider board to the heads and fired up the machine - Error 07! So, the main board is still "OK".

My shop guy is now reseating all the small head/sliderboard ribbon cables carefully. He's spent more time working on that JV3 than everyone else at this company, past or present, combined. If he's stumped, it's for good reason.

I just heard it power on a second ago, sounds like it he's done pluggin the heads back in...

He says it's still an empty test draw.

 

[Warped&Proud]

On a whim, and as suggested by the top boss thinking it might be extreme ink starvation, we raised our bulk ink wells.

No printed test drop - moves like it is trying to print but no ink comes out.

We then tried a small printed file. The head caddy moves as if it is printing but no print comes out. But the heads drip ink all over the place...

And now idle, the heads just drip, drip, drip ink...

My guy here thinks this is familier, like how this machine was not working before I started here and they had a tech here a year ago to get this machine work in the first place. He seems to think it's a slider board issue this time, just like the last time it broke down.

Thoughts? Suggestions? Sedatives?