Falcon Jr. Color Shift

[Finishline Signs]

My colors print starting out really dark then fade to the actual color. This started after the pad swelled and caused contamination. I have replaced all the dampers and drawn lots of ink through with a syringe. Do you think there is still some contaminated ink somewhere getting in the head? Where would it be coming from?

Thanks for any help.
Stuart

 

[randya]

Sounds like cross contamination.
When the capping pad makes contact with the head.
Ink is wicked from fuller cartridges to less full.

In the worst case it can drain all your ink carts into the waste.

Probably needs new cap or cleaning of the cap/MS.

 

[Finishline Signs]

I know cross contamination started it but why is it continuing. The cap station has been replaced and so have the dampers. So where is the contamination coming from. I figured there must be some in the dampers that would come out when it started printing but changing the dampers didn't help.

 

[Finishline Signs]

Bump for the morning crowd.

 

[CRD]

FWIIW,

If you leave it overnight after a good print.
Before you print take the carriage to the left and check the color cappin pad.
It should be CYM color. If it tends to have gone black then ink from CYM tubes leaking out the head on the cap sponge and mixed to black. Assuming the longer you wait the more black will be created from CYM ink.

Paco

 

[Finishline Signs]

The caps have screen on them so there is no way the pads are touching the heads. The pad does show the cmy colors. It prints like the photo everytime you print. It can be five minutes or 5 hours it always starts out with the dark color then fades to the correct shade.

 

[randya]

Are the drain lines clean?

 

[Finishline Signs]

The drain lines to the waste tank are free flowing. I have drawn ink through them several times with a syringe to try and pull out any contamination.

 

[CRD]

Finishline,

Did you already replaced the color head you have as backup?

If after the start the colors are getting better and after each stop they mix this must be the head only.
As long as there is sufficient inkflow from the CMY it has no change to mix. As soon as the head stops the ink has time to mix as there is no flow anymore.
Could be that inside the head a membrame damper layer is broken.

If the head keeps printing like this every time but always start with this I would add a cym colorbar before each print to be sure after that the colors are OK.

Paco

 

[Finishline Signs]

No I have not changed the head yet. I did flush the head out with cleaning fluid when I changed the dampers. I never thought of there being something in the head itself causing the problem. I have been printing a small patch of each color at strart of each job to keep from ruining the print. I am going to work on it some today and if I don't get anywhere I guess I will try changing the head.

 

[CRD]

Finishline,

Today I encountered a similar problem.
Do not know if your problem is solved but I will describe mine.

Start machine and do test print. Result all colors blank.
Do a cleaning and all colors are there only cyan missing nozzles.
So I clean again. Now yellow is disappearing.
So I clean again but yellow does not return.
I start a four color 50 x 2 cm print job and notice after 1 cm into the print yellow comes back but is dark colored. The magneta had a touch of cyan too. Finally thorugh printing the yellow returns.

So I clean again and whoops again yellow gone.
Start the four color job and yellow starts gradually coming back.
So cleaning makes it all worse while printing make the lines working.
But first the yellow is dark colored and also magenta. It looks like the cyan contaminate the yellow and magenta.

I disassembled the controlpanel so I can see what happens during cleaning.
Set up the video camera to record what is going on for later analyzing.
While the cleaning is busy I notice the wiper stays on its home position. Hum! Not ink at all on the wiper. The complete maintenance unit was replaced 3 weeks ago for a brand new one as was the print head.
When the cleaning is finished I try to move the wiper holder but it is stuck. While whiggling the holder it suddenly says click and it moves forward and backwards. Start the cleaning and whow the wiper is moving during the cleaning cycle. First and next prints are without missing nozzles and no dark start of the printing.

So if this happens again check the wiper on its function.

Cheers,

Paco

 

[CS-SignSupply]

Have you manually cleaned the head plates? Could be excess ink on the head causing dispersal of the ink drops... Even static can cause ink to travel from one part/color of the head to another.

 

[CRD]

Bobby,

Thanks for the info.
No I did not cleaned the head plates before it happenend.

Paco

 

[CRD]

For those who run into he same prboblem

Got the problem again of the dark start.
Checked the wiper and again the wiper was stuck. :-(
Removed the maintenance station and took out the purge unit with wiper.
The sliderpart where the wiper is attached on should move easily.
In my case it was not so I removed the two screws at the wiper side and carefully took the plastic side frame off. Take care there is a spring behind it!
While moving the sliderpart by hand I felt to much resistance.
As the whole unit was newly bought 2 months ago I could not think something was wrong. I disassembled the slide part furhter and found in between a residu of glue or something like that. I used washing petrol to remove all excessive residyu and chekced by hand force and voila it was sliding and rocking again.
Reassembled the unit and the maintenance station.
Now it cleans OK.

Paco