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UJF 7151 plus thread.

Smoke_Jaguar

Man who touches printers inappropriately.
Voltage is software controlled, lets the nozzles fire a bit hotter or colder to compensate for the random variation in a printhead. The power supplies in these things are pretty robust (and crazy expensive) and are regulated as well. Might just be coincidence, or ink issues causing it. Though white ink needs shaking near daily, color inks also need shaking every week or two as pigments can settle down.
 

Forty One

Make signs they said... It'll be fun they said...
Hey Smoke_Jaguar , if and when I need to swap out the head, is it as simple as disconnecting and swapping out? Or do I need to prime the head, adjust the drop pos, slants etc?
 
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Smoke_Jaguar

Man who touches printers inappropriately.
Since all parts have variability in them, alignments and adjustments are recommended. However, nothing wrong with just doing a swap and seeing how well it works, likely adjustments will be needed but you might luck out.
 

Smoke_Jaguar

Man who touches printers inappropriately.
I think I am going to toss my hat into the "This printer is garbage" ring.
Mind you, I have a 2015 era unit. So, things might have changed. Here's why:

1) Capping station, just a plastic tray, caps just drain straight into a pan that then goes into the waste tank. As far as I can tell, no real point of this other than catching drips.
2) Drips, holy hell, so much dripping ink. There is ink ALL over this stupid printer and only 2-3 absorber pads to catch some of it. It drips into the frame, it drips onto the sides, it drips all over the floor. This thing craps ink all over the place. Even the 48V power supply had a nice coating of ink ($1500 to replace should it burn out, but lucky on that front so far.)
3) Ink bottle stations in the worst possible place and off the worst possible design. 2 monster umbilical lines coming off these chonky units and they're basically floor level. Definitely would benefit from a nice clean top-left mounting.
4) Parts availability, just awful. Seems people did the smart thing and stuck to the UJF-6042 MKII line. Hard to find a lot of parts for these stupid things.
5) Noisy motors, insane high frequency noise output. If you can hear this stuff, it's like being in a room full of CRT monitors.
6) Suction/Wiper system is similar to the UJF-6042 MK1 type, thin sheet metal and they all seem to be bent out of shape/alignment. Total pain to mess with.
7) Price, even used, pretty awful. Not many 'good deals' to be had.
8) Use of recirculation heads, a great idea on paper, but poorly implemented in this printer. This thing feels like it came out of 2010, and somehow it's a current model. The Plus II version just has more heads and seems to share almost all the same parts. Got a suspicion Mimaki will abandon this form factor entirely and maybe just roll a bigger 6042 out on generation/MK III. Not sure even why it shares the UJF designation.
9) Head cables and the lack of replaceability. Chasing the cursed 12e error and it looks like I am going to have to buy an entirely new head. Toshiba's terrible design there. The heads seem to be epoxied or glued together, and the cable is permanently attached. Honestly, would've just been better to use CE4 heads. Wouldn't be able to pull off silver ink without the recirculation system, but at $1545 ($309 for 200mL at the time of writing this) a liter and no reason for the aftermarket to bother with this printer, no thanks.
10) Head cost at a minimum of $1600 each, and real option to just replace the circulator assembly. Not many of these kicking around, seems almost no other printers use these heads.

For some positives, the form factor is pretty nice. Has lots of unutilized potential. The circulator assembly above the heads is just a double subtank/heater assembly that CAN be cleaned up and rebuilt. Good luck finding any gaskets however and dust off a PZ1 screwdriver for all those tiny screws. Having 1 bottle of clear and white for a total of just 6 bottles is great and 2 channels worth of print per color compared to the 3042/6042 MKII is nice. Just gotta get this cursed machine up and running.
 

Smoke_Jaguar

Man who touches printers inappropriately.
When even your service manual shows ink all over the place, you know they intentionally let a terrible product be released.
 

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Forty One

Make signs they said... It'll be fun they said...
Side note, Is anyone running a primer and LH-100 inks on this?
From what I can see, only LUS-120 primer is available for this, but.... is it possible to say remover the 'clear' from my config and replace it with the primer?
 

Smoke_Jaguar

Man who touches printers inappropriately.
Primer is the ABSOLUTE WORST on pretty much any Mimaki UV printer. It destroys seals, caps, printheads, lines, etc. If I am rebuilding a machine, I dread cleaning that crap out. Looking at having to replace one of the CF1B heads in this one because of primer. They swapped it to clear before storage, having an insanely hard time getting more than 20% of nozzles firing.
 

Forty One

Make signs they said... It'll be fun they said...
Thanks.
Since I have not got a full size flatbed, I think I'll stick to manually applying it by hand
 

Smoke_Jaguar

Man who touches printers inappropriately.
Just had much better luck with brush-on adhesion promoters as well. I think I am up to 6 bottles of PR-200 just sitting. Occasionally manually apply it, but so many other options that seem to just work better. Not a bad idea on paper, but it seems to have a bad habit of priming the heads to adhere ink to them than it does the media you're printing to.
 

Smoke_Jaguar

Man who touches printers inappropriately.
Today was head flushing day, use the diaphragm pump on a Chinese print head cleaner and spliced in with Luer fittings to force circulate the ink a bit while draining off and replacing with flushing fluids. Don't forget to cap the subtank vent fitting on top to prevent it from dumping ink into the vacuum manifold filters. Also a good idea if using a version 1 capping station to make sure the line is draining when doing it. There will be lots of ink dribbling through the heads, want to avoid overflowing it.
 

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Forty One

Make signs they said... It'll be fun they said...
so, a re-circ pump system?
would love to see a little video of it in action if possible.
 

Smoke_Jaguar

Man who touches printers inappropriately.
The printer has a recirculator, I just bypassed it with a second pump to flush it out. No good diagrams of the ink system, so might record a video on the system in case other people are messing with this model.
 

Forty One

Make signs they said... It'll be fun they said...
Smoke_Jaguar did you have success in repairing the sub tank etc? I'm still getting the Overflow error on the K & white channels.
THinking it's time to dive in but I don't wanna destroy it even more
 

Smoke_Jaguar

Man who touches printers inappropriately.
At this point, I am writing the printer off as a massive lemon. So many idiotic design decisions in the early units, every expensive repair and every part that takes weeks to get just leads to another. Why some idiots at Mimaki decided to put in some horribly complex subtank system when Toshiba designed a circulator for that very printhead is absolutely beyond me. Updating the printer to a later version would cost thousands, and I think I'd still have a crap printer.
 

Tipgypsy

New Member
At this point, I am writing the printer off as a massive lemon. So many idiotic design decisions in the early units, every expensive repair and every part that takes weeks to get just leads to another. Why some idiots at Mimaki decided to put in some horribly complex subtank system when Toshiba designed a circulator for that very printhead is absolutely beyond me. Updating the printer to a later version would cost thousands, and I think I'd still have a crap printer.
Might be fun to just freeball it and make it work with bush fixes. Bypass all the sensors that act up. Put your own ink system together.
 

Smoke_Jaguar

Man who touches printers inappropriately.
I have the firmware cracked so I no longer have to use ink chips at least. Bypassing subtanks might be pretty tricky as I would need to loop in the entire ink system in a different manner. The subtanks also pull double duty as the heaters are located on them.
 

Tipgypsy

New Member
If I was going to try something - I'd do it on a single head, Use a refill tank on top, dummy bottle in the bottom to keep the sensor happy. Put a generic ink filter on the outlet and plumb tubing to the Head assembly without changing anything else. Run it for a while and see if it improves anything. Probably not that simple but maybe.
 

Smoke_Jaguar

Man who touches printers inappropriately.
Bottle tanks use a float sensor, so need a magnet taped to the 3 zone hall effect switch to bypass those.
 

Forty One

Make signs they said... It'll be fun they said...
I have the firmware cracked so I no longer have to use ink chips at least. Bypassing subtanks might be pretty tricky as I would need to loop in the entire ink system in a different manner. The subtanks also pull double duty as the heaters are located on them.
Go on.....
 
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