Please take a look at the attached picture

[mustafade]

Hello All,

Please take a look at the attached picture and you'll know what I'm trying to ask. I didn't know how to describe the problem. Sometimes a picture worth thousand words.
Could anyone suggest what causes two tone effect and how to remedy the problem. One band is slightly lighter than the other.
I can tell you this, it is caused by the magenta and it prints a beautiful test draw on all channels as well.

Thanks very much for your input!

 

[artbot]

recently there was a discussion about a banding issue with the dx4 head that was unavoidable even with perfect calibration. ...think it had to do with some particular pass configuration.

 

[mustafade]

Hi Artbot,
Thanks for the reply. Ok, so this problem is also categorized as banding. I learn something new everyday. Awesome!
I thought about that and read that particular post as well but I was printing with this 4 pass 540x720 res quite sometime now.
However, recently I have replaced couple of yellow dampers which I have recycled these particular dampers due to fact that they were brand new and they sucked some cleaning fluids in side them so I saved them because I didn't know if they could be cleaned and reused again at that time.
These particular dampers were on magenta and after I cleaned them I placed on to yellow line.
On my previous post I did mentioned that the problem color was magenta but now I am thinking it could be yellow as well.
Artbot! Any thought about the replaced dampers?

Thanks again!

 

[artbot]

i've recycled dampers, if they look clean, they shouldn't be a problem. i've stuck dampers in ultrasonic before. that gets them back to brand new. you'll first have to prove which color is starving/banding. put together a file of c m y and k blocks and print them. see if one color looks bad during printing. after that, it's a matter of doing a damper swap with a working line to see if the issue migrates.

 

[NEGD]

Hello All,

Please take a look at the attached picture and you'll know what I'm trying to ask. I didn't know how to describe the problem. Sometimes a picture worth thousand words.
Could anyone suggest what causes two tone effect and how to remedy the problem. One band is slightly lighter than the other.
I can tell you this, it is caused by the magenta and it prints a beautiful test draw on all channels as well.

Thanks very much for your input!

This looks a lot like what our particular problem was. We equated the issue with a technician coming in for maintenance, but after responses to my thread, tests, calibrations and more I've come to the conclusion that this is something unavoidable with the Jv3s. I still do not know what causes it to "start" happening, and I haven't completely "fixed" the issue, but here's MY workaround.

1- When I print on thicker material (3M 680) I have to keep my carriage height on high, but thinner materials (3M 180) on low. This helps to make this banding much less apparent.

2- There seems to be a loss in communication or something when the carriage makes a certain number of passes (I'm thinking on the 8th pass) so I currently run the printer on 720 8pass bidi BUT with my more color/quality important jobs I up to a 16 pass. This makes the "lighter" bands closer together.

3- We were seeing it primarily in the cyan but it was happening in all the colors and we were also getting perfect test draws. Part of our problem was that our cyan print head was installed slightly off. Once this was fixed, and calibrations were done for the bidirectional printing it's been all but eliminated. I would suggest if you don't have a service manual or aren't under contract to hire a technician to come in and calibrate.

The banding (loss of proper ink coverage) is still there but not nearly as noticeable and we're back to getting jobs out the door. Let me know if you have any questions, I dealt with this for a week or so and it's very frustrating.

 

[NEGD]

Here's the link to my thread... it may help you understand the process I went through.

http://www.signs101.com/forums/showthread.php?t=82835

 

[Case]

recently there was a discussion about a banding issue with the dx4 head that was unavoidable even with perfect calibration. ...think it had to do with some particular pass configuration.

Mustafade is using a dx5 head, so that conversation has nothing to do with him...

Case

 

[Sticky Signs]

Does it do the same thing in uni-direction mode? If not, it looks like a case of "lawn-mower" effect.

 

[mustafade]

Mustafade is using a dx5 head, so that conversation has nothing to do with him...

Case

That is correct! My printer is a JV33.

 

[mustafade]

Does it do the same thing in uni-direction mode? If not, it looks like a case of "lawn-mower" effect.

I did not try it with Uni-directional mode yet. But i know one thing it was not doing it before on 4pass 540x720 bi-directional mode.
What is a lawn-mower effect?

Thanks for the input!

 

[mustafade]

i've recycled dampers, if they look clean, they shouldn't be a problem. i've stuck dampers in ultrasonic before. that gets them back to brand new. you'll first have to prove which color is starving/banding. put together a file of c m y and k blocks and print them. see if one color looks bad during printing. after that, it's a matter of doing a damper swap with a working line to see if the issue migrates.

Hi Artbot,
Yeah they were clean, although there was a hue of magenta left but I don't think it would effect this kind of a problem.
What kind a solution(cleaner/detergent) are using on your ultrasonic cleaner. I use simple green on mine to clean my guns/reloading parts and it does OK. But I would be hesitant to use same thing for the dampers.

I'll try the CMYK blocks and post the results.

Thanks for the advise!

 

[SightLine]

Have you run a dot position adjust lately? Might help some - not really sure though. Thats a pattern I've not yet run into on our JV33.

 

[mustafade]

This looks a lot like what our particular problem was. We equated the issue with a technician coming in for maintenance, but after responses to my thread, tests, calibrations and more I've come to the conclusion that this is something unavoidable with the Jv3s. I still do not know what causes it to "start" happening, and I haven't completely "fixed" the issue, but here's MY workaround.

1- When I print on thicker material (3M 680) I have to keep my carriage height on high, but thinner materials (3M 180) on low. This helps to make this banding much less apparent.

2- There seems to be a loss in communication or something when the carriage makes a certain number of passes (I'm thinking on the 8th pass) so I currently run the printer on 720 8pass bidi BUT with my more color/quality important jobs I up to a 16 pass. This makes the "lighter" bands closer together.

3- We were seeing it primarily in the cyan but it was happening in all the colors and we were also getting perfect test draws. Part of our problem was that our cyan print head was installed slightly off. Once this was fixed, and calibrations were done for the bidirectional printing it's been all but eliminated. I would suggest if you don't have a service manual or aren't under contract to hire a technician to come in and calibrate.

The banding (loss of proper ink coverage) is still there but not nearly as noticeable and we're back to getting jobs out the door. Let me know if you have any questions, I dealt with this for a week or so and it's very frustrating.

Thanks for the detailed information but I don't believe it applies to my problem due to my printer being JV33. I should have mentioned on my first post. It is clear to me even more now that you guys can't read minds either.
Thanks for trying to help NEGD

 

[mustafade]

Have you run a dot position adjust lately? Might help some - not really sure though. That's a pattern I've not yet run into on our JV33.

Not long ago I hired a tech to change my JV33's print head (which was total waste of money because I know now there wasn't anything wrong with my print head, they took advantage of my lack of knowledge about JV33's) anyways when he put the new head he did all those tests.

 

[mustafade]

Attached picture is the CMYK test 1" blocks I even did a 100%Y & M=RED.
It looked good to me.
I don't get it ya'll!
I did not get this much challenge from my good old Epson9600, I still don't.
JV33 a solvent beast thou that's why.

 

[SightLine]

Actually I was callign it the worng thing.... its Drop Position Correction under Funtion>Maintenance>DropPos.Correct. It is a user function that you should do about once a month. Pretty easy - uses about a 2 feet of material.

Run it and you will get 12 (pretty sure) sets of lines. Once they print you just enter the best aligned one for each of the sets on the control panel.

May or may not help your problem though.

 

[mustafade]

Actually I was callign it the worng thing.... its Drop Position Correction under Funtion>Maintenance>DropPos.Correct. It is a user function that you should do about once a month. Pretty easy - uses about a 2 feet of material.

Run it and you will get 12 (pretty sure) sets of lines. Once they print you just enter the best aligned one for each of the sets on the control panel.

May or may not help your problem though.

I'll try, good tip. Thanks, SightLine

 

[HulkSmash]

It could be a feed adjustment. Usually when you get light banding your % is too high and if its dark it's too low

 

[mustafade]

It could be a feed adjustment. Usually when you get light banding your % is too high and if its dark it's too low

The very first picture I posted was after I playing with feed comp. I did up or down values in increments of 2 as high as +-10. Still didn't change the quality. That is what you are referring right? Feed Comp.

 

[Sticky Signs]

lawnmore effect is a bit tricky to explain but I'll try. When the head travels from left to right, it fires the inks and the ink droplets land on the media. The ink does not land perfectly straight with the media though because of the momentum from the head traveling. Now, the same thing happens when the head travels from right to left only this time the momentum is in the opposite direction which means the droplets from the second pass are slightly different from the ones in the first pass. So the two pass are in essence opposite of each other. Kinda like the lines one get in your lawn after mowing it.

I hope that's a good enough description... I'm still on my first coffee.

I find that certain colours are always problematic no matter how well tuned my machine is. When faced with the issue, I just run the job in uni-mode and that usually takes care of the problem.