Color Variations on JV33

[Centro Graphics]

Hi guys.

Wonder if anyone can advise whst is causing color variations in panelled print?
Basically we are printing a solid color over a 15 ft width, which of course we are tiling. The problem is the panels are printing slightly different but enough to notuce. Same file, profile, inks. I cant work out what the problem is.
Any guidance appreciated

See attached photo.

We have a JV33 and have it from new for 6 years.

Thanks

 

[SightLine]

Could be a number of things but one thing to ask is what RIP and does your RIP give an option to automatically flip every panel? Most RIP's do have that as an option. The reason being is that every printer will have a very slight difference from the left edge of a print to the right edge. The wider the print the more of a difference. I know Flexi has this option "automatic tile flip". The idea is that every other panel prints upside down from the next so that when 2 panels are put together both edges were printed on the same side of the printer.

 

[Centro Graphics]

Thanks for the advice on that, We use Rasterlink 3 not sure if it has the option, will try it and see if it works when back in tomorrow. Never seen it before, thought it might be and ink distribution problem.

 

[Centro Graphics]

Hi sightline. Our RIP does allow flipping but still have same problem. Still on same job, half way through 6 trailers. Changed profile still no joy. Any other ideas? Atrsched photo.

Thank you

 

[Bretbyron]

Weird! Is it print to print or side to side? Meaning, if you flip one upside down do the colors match or can you tell if there is a gradient shift from one side to the other of each print? Different temperature from morning, noon and night in your shop while printing?

I just did a five panel wall wrap with our JV33-130 using Rasterlink5 to do the tiling and it looks great. I didn't use any flip option, but the graphic has a lot of rich dark tones. Is your media old?

 

[SightLine]

I'm thinking that this is ink starvation (we can very well be intermittent) and that either (or all) the capping top, dampers, and wiper might be due for replacement. All are consumable parts which must be replaced periodically.

 

[Centro Graphics]

Bret

If I flip the panels in the RIP then two are foot to foot, but the other 2 panels are head to head so getting a better result from the foot to foot panels, but not the other two. I have never seen this before and is annoying.

To be honest the two pics I uploaded are really bad examples of the problem, will do a couple more.

Sightline
Yes you maybe right on the ink starvation, but why/ how would that cause this problem. We print say a 16ft (w) x 8ft (h) in 4 panels vertically, each of the 4 prints bottom to top. When panel 1 is done, it starts again (bare with me) on panel 2. I just don't get why it would have such a colour change. The problem does not seem to be at the top of the panels when output like this.

I have recently changed the wiper and had a new capping station in the last 12 months fitted by an engineer as part of a service.

I have thought about the feed speed from the rollers, but have never touched that in all the years.

Its saturday morning here now, this has got me outta bed early, so am gonna try a big clean and a flush, although I must say that on a test draw the lines are almost perfect.

Your help is greatly appreciated, thanks a lot.