UJF 7151 plus thread.

[Forty One]

THink it's best I start a specific thread to this unit.
Me thinks I'm going to have alot of questions.

I've been receiving errors stating that the UV lamp is overheating.
Using the mitsubishi Acr ex001 profile.
1200x1200 re3s. Uni Directional

I am currnetly printing a base white. approx a 500mm x 400mm coverage.
It gets about a third the way through then it stops and gives me the error 'UV LAMP OVER HEAT".
I've flushed the antifreeze and replaced it.
Checked that all the fans are clean and the radiator is clean. However I keep getting this error.
The lamp has done a bit over 1000 hours.

ANy advice?

 

[Smoke_Jaguar]

The UV LED arrays are cooled by a heatsink on the UJF 3042MKII/6042MKII/UCJV300 (and the 7151, I think), it's the same module. Check mist filters, make sure the heatsinks are clean and air is moving over them. As soon as you start printing, those fans should be running, and they will keep running for a couple minutes after a print. You can also check the temperature readings under the #Test>Sensor menu. Each LED board has 4 temp sensors, each covering it's corner of the LED lamp array. If getting weird temps (-137C), could be a broken thermistor.

Alternatively, there is a chance the thermal paste bonding the LED boards to the heatsink is cracked/dried up. Can just use heatsink compound like you'd use on a CPU after cleaning off the old stuff with alcohol.

 

[Forty One]

thanks.
i assum,e you mean the board attached to the head?

 

[Smoke_Jaguar]

Correct, the LED circuit board tends to be aluminum or copper backed circuit board that's bonded to the heatsink with thermal paste.

 

[dudeinthemoon]

I’ve seen these radiators swollen many times mostly on big JFXs, it made from aluminum and if it’s not clogged or cracked the hammer with wooden plank will turn it back to normal pretty easy

 

[Forty One]

How often is the "Ink Overflow" error acceptable?
It seems that after I put my machine to sleep for a day or two and then turn it back on, the error pops up and I need to correct one of the white ink channels.
it's the same channel all the time and it's eaten quite alot of the white ink from that bottle.
If it seems to be a little more than average, is there something I should be looking at in the overflow tank?
I could assume alot now based on ink properties, etc, but rather than fueling that fire I would like to get a little feedback from someone who may have a more specific answer

 

[dudeinthemoon]

Forty One,
It’s not acceptable at all. This indicates possible problems with air pressure filters or air valves (or both) on upstream

 

[Forty One]

Is this an "easy fix"? E.G, something a standard maintinence plus a couple of consumables be the answer?

 

[dudeinthemoon]

Nope, not easy, few covers and parts to remove to reach it
Air valves and filters located at the top of carriage, it has two sets for downstream and upstream, the issue is most likely in upstream which is under downstream valves

 

[Forty One]

When I am printing braille, I'm getting a little ghosting when I'm printing multiple layers on the print side of the character.
Is this a levelling issue? I briefly remember a mimaki rep commenting on something like this way back, but I'm unsure.
Then... How can I adjust this?

 

[dudeinthemoon]

Seems like cyan overspraying, that’s z sensor issue it detects the media thickness incorrectly, when your head gap is more than 2mm from the media it will be overspraying

 

[Forty One]

Can anyone tell me what this is and what should be in it?
Bottles at the back of the machine.

 

[dudeinthemoon]

That’s air pressure bottles

 

[Forty One]

I've been receiving errors stating that the UV lamp is overheating.
and gives me the error 'UV LAMP OVER HEAT".
I've flushed the antifreeze and replaced it.
Checked that all the fans are clean and the radiator is clean. However I keep getting this error.
The lamp has done a bit over 1000 hours.

So as it turns out, it had nothing to do with the sensors etc.

I noticed that the coolant was not circulating throughout the machine. And at first I thought it was the pump.
I replaced the pump but still nothing.
The reservoir tank had a bit of debris in it, so I cleaned it out and flushed the entire system out.
I found that the heatsink was partially clogged from the debris. it was a bit hard to push the coolant through it.
After pushing all the crap out, refilling the coolant and purging it of all the air, I've resurected the machine.

So, the techie from mimaki was wrong and I saved myself a few thousand in turn.

 

[Smoke_Jaguar]

Nice fix. And yeah, the heaters can build up a crazy out of gunk for a sealed system. Make sure to get the propylene glycol ratio right and should keep things from growing in it as well.

 

[Forty One]

I'm now trying to adjust the head gap to get rid of the overspray/mist I am producing when printing braille.
setting the media (18mm thick) and head gap is 1.5mm, table is 135mm.
I use my shim that is 1.6mm aluminium to check the head gap. It slides in there with no obstruction and I can clearly see there's more space between it and the head. probably atleast another half a mm.
So... how do I adjust this?
if I change the values on the LCD in the menu, it changes the height of the table and media thickness if I try to adjust this via the menu.
Is there a particular setting in #adjust where this is done?

 

[dudeinthemoon]

You need good feeler gauges for that.
Go to #table adjust and adjust the height so you’ll get 1.5 gap in all 4 corners and the center of the table. This may doesn’t need adjusting, just make sure the gap is right and begin adjusting the Z sensor

 

[Forty One]

thanks.
The "Slider", is this a physical attachment thing I need? or is it already the aluminium casting that is attched to the head?

 

[dudeinthemoon]

None of these, just press enter to confirm
I think that’s carriage movement related, but I’m not sure

 

[Forty One]

These are the current images after going ton#adjust menu...