UJF 6042 - Test Prints after Head Replacement

[PlanetPrinter]

Hi All,

I replaced a print head on on of my Mimaki UJF-6042 printers today. The print head that was removed had significant clogs in the nozzles, and was affecting the colors of my prints. The nozzle recover function was enough to get me by for awhile, until today.

Anyways, I replaced the head and ran the test print; here's what printed out:

The thing that really sticks out to me is the magenta mix in the cyan area (aside from the HUGE bands of Cyan).

Any ideas whats happening here? I've replaced a few heads already on the other printer, but haven't ran in to this issue before.

Thanks for the help!

 

[WalkerP]

The new head was brand new and OEM? Check your ribbon cables. Make sure they're seated correctly and not scorched.
You're doing normal cleanings between each of those test prints or just reprinting?
Do the cyan streaks happen when printing too or just during nozzle checks?
I'll give my opinion once I hear back. Hopefully the cables just aren't seated properly...

 

[PlanetPrinter]

The new head was brand new and OEM? Check your ribbon cables. Make sure they're seated correctly and not scorched.
You're doing normal cleanings between each of those test prints or just reprinting?
Do the cyan streaks happen when printing too or just during nozzle checks?
I'll give my opinion once I hear back. Hopefully the cables just aren't seated properly...

Here's the TL;DR on the situation: Bad ribbon cables/connection on printhead.

I had tried cleanings between each of the test prints, but got the same results. I didn't attempt to run an actual print, just test prints. I removed the cables and re-seated them 4 times, but still got the same result. After checking all of the connections to the board, damper, and ink lines, etc, I decided to just swap in the old print head and see if I got the same results. The old head printed out just fine (with the exception of numerous outs in the Cyan and Magenta nozzles). I've run a few more test prints and I'm not experiencing the Cyan banding anymore.

I have a feeling you were led to the conclusion that the PCB Slider board needed to be replaced?

 

[WalkerP]

I was leaning towards a bad head out of the box. I've had that happen more than a few times, but I've also seen the exact same thing on other UV printers with Ricoh Gen4 heads as well where they did that weird banding and then just stopped.
UV printers are a fairly new beast for me, but I've seen that banding hundreds of times on solvent and H20 based printers. 99% of the time it was electrical failure/cable issue and 1% of the time it was a mystery.
So you're back up and running? If so, glad to hear. Chalk it up to a lesson...?