White Spots in Print

[wolf]

Hi Everyone,

Everything has been going well until one of the colours dropped out.

I checked the dampers and these were loose so I changed them, problem fixed and back to printing I went.

What happened next has mystified me. I started to get white spots on the print. The printer does not print white but the area has not been filled with colour.


I am not sure if the dampers were contaminated but I can only point this issue to a few things.

1. I remember either on the day or a day after or a day before hand I touched the printer to switch on and I got a small static shock when I touched the printers control panel to switch on.

2. I have used 3 different rolls of material and I still get the same issue which rules out the vinyl.

3. A day or so latter I checked the printheads on the printer and had noticed a bit of fine dust sitting on the print heads, pump tubes etc which I blew out with a an air gun.

4. I increased the heaters slightly but has not helped.

The printer sits on lino not carpet.

Has anyone had this problem and has found a fix around this problem.

I initially blamed the dampers in which I have ordered some more but I am now thinking it could be the static and if it is how do I fix it it?

Your help would be appreciated.

Thanks

Joe

 

[GAC05]

Hi,
Not sure I can help but can you supply some more information on the problem?
What brand/model of printer do you have?
What do the dropouts look like? Spots or streaks of missing color (have a photo)? dropouts?
Does it happen 100% of the time or is it limited to a particular file or even a single type of material?
I think most of the really smart types are asleep right now but they should be able to help in the morning with a few more details.

wayne k
guam usa

 

[wolf]

Thanks for your reply.

The only issue I have right now is the white spots. I have attached an image with a sample print.

This has only started since I changed the dampers. So either the dampers are contaminated with something or its something else.

Can't remember but within 24 hours of changing the dampers when I touched the printer switch to put the printer on it gave me a stong static shock.

I have tested 3 different rolls of material and its the same issue on all so it is not the vinyl.

I thought it may be the dampers but now I think it could be the static build up because I do pull the power plug off the wall when working on the printer. When I removed the cover and checked the print heads there was tiny bits of dust all over the printhead and surrounding areas.

Printer: Fully Converted Roland FJ 52.
Inks: Roland Eco Solvent Inks.
Heating System in Place: Yes 3 heaters temp controlled.
Amount of rolls printed before I encountered problem: About 3 Rolls.
Have I encountered this issue before? No.


Thanks for now.

Joe

 

[GAC05]

Joe,
I think I am out of my zone, the only time I have seen something like that is with media contamination and you said it shows on more than one roll.
This is a pdf from another thread here, take a look and see if it looks like their sample.
http://support.rolanddga.com/docs/D... Services/Manuals and Guides/RTG_Fisheyes.pdf

Once the experts start waking up early morning US eastern time someone is bound to log on and have the cause nailed down.

good luck

wayne k
guam usa

 

[wolf]

Hi no I am very familiar with fish eyes which occur if there is contamination eg water or during a solvent conversion.

Fish eyes tend to have an upper lip around the ring of the fish eye.

If anyone has any ideas please help.

THanks

Joe

 

[wolf]

Can anyone help me with this please?

Joe

 

[kffernandez]

personally, i don't think your machine nor your media has anything to do with your problem - since it happens so randomly.

my first guess would have been fish eyes. but since you ruled that out, the only other source i can think of is dust getting onto the media - getting printed on - and then falling off afterwards, leaving a nice clean white spot.

how about you give us a better magnification on the white spots?


kelly

 

[alias1]

the infamous "white spot"

Hi guys, i too have experienced the same problem.
machine: RS-640
ink: Platinum advantage

i have established that its caused by my magenta(am busy with batch to batch consistency). I have tried 2 different types of Avery (high dot gain and low dot gain) and still get white-spotting. I tend to think it could be related to the firing of the nozzles. I assume that the white spot represents a droplet that never got fired, or a droplet that wasn't fired with sufficient force. thats just a theory, will have more news once ive conducted more research... ciao..

 

[Gabriel]

I would blame this only on the material. Where the white spots are, the printer does not menage to put ink there. Actually the ink do not stay in that area (humidity - I guess).
How are the heater settings? Try to increase the heat on the print area.

 

[CARVER]

Having the same issue. Did you ever find out what was causing the spots?

 

[asylbek1]

some ideas

1) it's material fault, i think. sometimes got the same issue on dark tones with high inklimit coverage.

2) the problem in rolls of the printer - try to clean'em

3) bad earthing also may cause the problem.

 

[Tim Kingston]

Suggestions

Three suggestions: contamination from the environment in the form of someone spraying nearby, even in the next room ( acid wheel wash, adhesive promoter ), HVAC outlet nearby with dirty filter. Also, if your printer has a protective translucent spray shield covering the heads/ dampers make sure all the clips etc. are in place again and there is no possibility of that plastic rubbing against the rail etc. I had that problem once, producing very minute white flakes.

 

[ItzFriko]

Greetings, members.
I have been facing the same issue for almost 2 weeks now, and I've tested on all the vinyl media I have (3M - Avery - Orajet - Oracle) as well as banners tarpaulin, it shows white spots all over the print and it has affected my quality resolution of the year.
I truly need to solve this issue ASAP, not sure if anyone has solved this but i need an answer.

My machine's details:
3.5 meters wide fully converted to Epson's DX7 with all the boards and tubes.
Galaxy DX7 for ink
All nozzles work perfectly well.
the floor is tiled and fully balanced.

please if anyone has an answer, let me know.
Thanks

 

[InkHead]

We had this issue when we got the Epson s80600 earlier this year. It turned out to be dust particles. We never noticed it before the s80 because we used UV printers and I guess the ink is so thick it would just cover any dust.

What we do now before we start a print is use one of those sticky silicone rollers for the first couple of feet of the roll before we print. Has solved the problem. We also use a Swiffer as we are laminating just to make sure we get everything.

 

[LiqueColor]

The problem is with the media. You have plasticizer migration which is causing the ink not to stick in those spots. Plasticizers are what make a vinyl soft and flexible. Normally this is caused by improperly and or old stored media.