Gandi Jeti 3150 question

[Charliekarly]

Hello, I am a Novice at operating the Gandi Jeti 3150. It is a 6 color with fedora core. I am running a hot job and I keep losing my black heads in bank A, the front head in bank A is brand new. I am running at 12 pass / 100% density. This job needs all 4 black heads. The Tech that I called last week said it was a miscommunication to the I/O board and to reset the boards then re-open all the windows and purge. When I lose the black and get a bad print I run a jet-out test and both heads numbers 10 and 11 all the jets are not firing. when I purge/prime the heads all I get is air or bubbles. eventually they come back but the problem keeps happening at random (to my knowledge). My low vacuum setting is at 30, and all the head voltages are close to 108. Thanks in advance for any suggestions!

 

[Typestries]

There could be 2 issues, electrical or ink. From your comment about air bubbles when priming, I'd further investigate ink first. Sound like ink is not getting to the reservoirs which can be caused by a bad pump, clogged filter, check valve fail or clogged reservoir (the PITA problem).

Look at screen 2 and your pump counts and reservoir levels. Is the pump request and count going up? Reservoir level off? Post a pic that would be helpful.

 

[Charliekarly]

Res. levels

My reservoir levels are taking a long time to fill up, what would you like a picture of?

 

[Andy D]

If you're getting air bubbles I don't see how it could be a IO problem
especially if it's intermediate.
Sounds to me either bad ink, bad filter, an air leak, or maybe a low vac problem ....
Watch your low vac tubes next time you prime, does one or more suck ink up into them?

 

[Andy D]

Also, on a side note, your new head should not be at 108 volt, they usually start at 95-ish
and work their way up as they get older. there should have be a printed test paper slip on the box your
head came in telling you what to set your head at.

And, a 30 low vac seems high, I keep mine 27 - 27.5

What are your reservoir and head set point temps set at?

 

[Charliekarly]

Check valves

We replaced the check valves and the problem is still occurring. Any of the settings (i.e. Low vac and head voltage) were set by the technician himself. All of my tubing is black plastic so I cannot visually check the lines. This printer has been one problem after another, I am feeling defeated!

 

[Andy D]

I feel your pain, ours was like that until I learned all of the things to watch for, now it's a work horse.
The ink supply lines will be black but what you need to watch is the clear ones going into the square boxes
in front of the heads but mounted to the left and right of them... does that make sense? If not I will take a picture.
Also, check all of the fitting going to the heads and make sure they're tight.

 

[Charliekarly]

I have not gotten any ink in the overflow. I am relatively new to this, just out of curiosity how did you learn all of the things to watch for? I really want to find a class or some sort of training for this press!

 

[Andy D]

I learned everything about the Gandi 3150 Flatbed on the job, I have worked at two different
places that had them. I doubt there is any class, they don't even make that model anymore.

Okay one more question & this is the most important one: Who are you buying your ink from?
If it's from Gandi then I can guarantee you you will have nothing but trouble.. their ink is horrible
and so is their tech support. Back when we used their ink we started losing nozzles/heads too
and some of them were new. I would pull the heads to try and clean them and I noticed globs
of stuff in the cleaning solution.. I then poured new ink from them thru one of those funnel paint strainer
and there were globs in that too. We switched to Agfa ink (they bought Gandi out) and have not had issues
since, and we get great and free phone tech support from them.

 

[Andy D]

But this is the steps I would take in your situation until it was fixed:
1. check low vac
2. check all the connections in the print head box to make sure they're tight and there are no leaks.
3. I would pump out the ink of the color I was having issues with to see if trash got down there that was blocking the intake.
4. I would run the ink I pumped out and any new ink I was going to refill the tank with through a strainer , or even a couple of those
head wipes to see if there was trash in my ink.
4. I would change out the filter one the back of the ink tank. You don't want to clog up a good filter with crap ink

5. change the check valve.
6. pull the heads to clean them and maybe switch the heads around to see if the problem follows the head * make sure your ink good before you do this
or you could mess up more heads
7. I think that would only leave a bad pump... switch them around to see if that fixes the problem.

 

[theyllek]

I had this problem at my previous job on the same printer, two different times.

Replaced check valves, and filters. We replaced an ink pump at the main reservoir in the back which fixed our air bubbles in the ink lines and and the reservoir in the carriage not filling fast enough. I was able to nurse a few jobs through by watching the reservoir levels in Snap Diagnostics window and if they dramatically dropped immediately pausing it until it came back up.

We also had to replace one of the boards the heads plug into in the back, I can't think of what the proper name is. It's about the size of your hand and four heads plug into it.

Your low-vac would be the first thing I would tell you to check. Making sure it hasn't pulled ink into the lines and down into the manifold. If you have frequently low-vac issues, make sure there is no water in the tank. Moisture in your low-vac lines and you'll have a bad day. Same goes for your compressed air lines. proper working compressor and moisture traps go a long way into solving lots of pesky problems.

I'd love to tell you I took a class or had a lot of in depth training, but about a day in a half of on the job from the previous operator who didn't know a whole lot, followed by a lot of time flipping through a lacking ink stained manual and watching every single thing a tech did when they were there. Also - I screwed a lot of stuff up.

Good Luck! When they are running they are a work horse!

 

[Charliekarly]

Sorry for the delay!

We swapped our ink filters and the problem has not happened since. I will nag my supervisor to replace my low vac tubes, for they do have condensation built up in the lines. Within this month we have replaced all of our buildings compressed air lines, Thank you so much for all of your help!

 

[Andy D]

I will nag my supervisor to replace my low vac tubes, for they do have condensation built up in the lines.

I'm glad to hear it! BTW, don't worry about replacing the low vac tubes, they always seem to have condensation...

 

[Charliekarly]

i have an urgent question!

I won't bother with the low vac tubes but right now I ran in to a problem.............. a screw came loose in one of my shutters for the UV lamps, it scratched my quartz glass, and it won't go back in, I think the hole that the screw goes in to is stripped. I even tried another screw and that wouldn't go in either. My question is can I still print if I just remove the screw? I will attempt to attach a photograph. TYIA!

 

[Andy D]

Yep, our's did the same thing, but you're lucky, the screw managed to bend the crap
out of one of our shields & if I remember correctly it was $1200 just for the replacement shield.
I would say heck yeah, you should be fine with the remaining two screws.
Our 3150 is going on 11 years old now ( I think) and it's still a work horse
but we had to bypass & rig tons of stuff on it over the years.

 

[Charliekarly]

Thank you so much!

You have been nothing but helpful to me, I really appreciate it! I was actually able to get the screw back in, I was unaware there was a nut that slides around in there. After taking a closer look I was able to use a really small hex key to move it back in to place and fix the loose screw! I will remember for next time that (if need be) I can go without the screw! I like to listen to my press while it runs, so I was lucky enough to hear where the sounds were coming from and pinpoint the issue! I will come back to this thread if I ever have any more questions!
We have only had this press for a little over a year now, Before the Gandi we had a Nur Tempo. So far I like the Gandi better, It's just that the computer has a lot of glitches and the learning process can be a pain sometimes! I myself have only been a digital press operator for maybe 2 years now. So I still have a lot to learn!

 

[Charliekarly]

I could use some more advice..

I am having a few more problems with the Gandi Jeti 3150.

First, My middle vacuum hose for the table has now collapsed for the second time. I'm not sure if it is for the same reason as the first time it happened. The first time there was a "tear" in the hose and i replaced the hose about 6 months ago, and now the new hose has collapsed in a few places and keeps getting stuck. I'm certain that eventually i will have to replace the hose again. My question is does anyone know why this is happening, do I need to poke all the vacuum holes on my press bed? Is there a clog somewhere causing too much pressure? Maybe the hose is getting too hot and weakening.
Second, I am having issues with my black heads again. Sometimes the black won't print through all the nozzles but not as bad as last time. My main concern is that this is a new head (a couple of months old) and it has already started to look pretty bad in the "Jet-out" tests. The bottom rows are blurry, the numbers aren't printing clearly, and there is an issue with misfiring nozzles and what-not. When I am printing black copy I get a really poor quality print. I do not want to have to replace this head every couple of months!
Here are a few of the adjustments i have tried.
-I raised the head voltage up to 110 (from 107) in heads #10 & #12 (the 2 front black heads).
-I raised the ink reservoirs for black by 2 Degrees (now at 47 while the rest are at 45)
-I raised the head temperatures by 3 degrees (not at 50 while the rest are at 47)
-I wiped the print head with solvent during a prime
-I adjusted the color alignment

I will attach photos of the "Jet-out" test, and a sample of the quality i get printing black copy.

Any and all suggestions will be greatly appreciated!

 

[Andy D]

I am having a few more problems with the Gandi Jeti 3150.

First, My middle vacuum hose for the table has now collapsed for the second time. I'm not sure if it is for the same reason as the first time it happened. The first time there was a "tear" in the hose and i replaced the hose about 6 months ago, and now the new hose has collapsed in a few places and keeps getting stuck. I'm certain that eventually i will have to replace the hose again. My question is does anyone know why this is happening, do I need to poke all the vacuum holes on my press bed? Is there a clog somewhere causing too much pressure? Maybe the hose is getting too hot and weakening.

This has happened to me a couple times, it was because the replacement hose was too long or too short, I can't remember. It probably wouldn't be a bad idea to put some kind of spring around the spot it double backs on itself so that
spot doesn't kink.

Second, I am having issues with my black heads again. Sometimes the black won't print through all the nozzles but not as bad as last time. My main concern is that this is a new head (a couple of months old) and it has already started to look pretty bad in the "Jet-out" tests. The bottom rows are blurry, the numbers aren't printing clearly, and there is an issue with misfiring nozzles and what-not. When I am printing black copy I get a really poor quality print. I do not want to have to replace this head every couple of months!
Here are a few of the adjustments i have tried.
-I raised the head voltage up to 110 (from 107) in heads #10 & #12 (the 2 front black heads).
-I raised the ink reservoirs for black by 2 Degrees (now at 47 while the rest are at 45)
-I raised the head temperatures by 3 degrees (not at 50 while the rest are at 47)
-I wiped the print head with solvent during a prime
-I adjusted the color alignment

I will attach photos of the "Jet-out" test, and a sample of the quality i get printing black copy.

Any and all suggestions will be greatly appreciated!

Who are you buying your ink from?
Are you doing solvent flushes at all?

 

[Andy D]

1st off, you see how you lines in the jet-out that starts at 128 are mostly even with each other left and right?
That's how it should look if your voltage is set right. Your heads starting at 384 are set too high or too low, you need to
tweak your voltage until they line up.

It looks like you're not running all your head at 100%, right? You're tweaking some higher some lower to adjust the color , correct?

2nd your jet out doesn't look bad at all, Mine is much worse than that and print much better than what you're getting.
What do your other jets look like?
Can you reprint the "EXT" in uni- direction so we can see how it looks....?

 

[Charliekarly]

The colors are ALL at 100%.
all of my other jet outs are beautiful except for the black i showed you and light magenta has been iffy since I got the machine.
The first sample was at 12 pass 100% Bi-Directional on coroplast. I am getting ready to leave for today so all i got a picture of was the same file at 18 pass 100% UNI-directional on max-metal. Tomorrow I will use your advice and adjust the head voltage until they line up.