Clear Ink flake Problems with Mimaki UJF-7151 plus

[Samnas]

Hi Guys .... not much to find about the UJF-7151plus around here. We are using this machine besides the JFX500 for about two years now and experiencing quite some problems with the clear ink in the UJF, especially while printing on Polystyrene. After a few runs the clear ink head is always full of ink flakes that are tough as little rocks. Not really possible to get them off the head with softly wiping …. wished I could use a metal scratcher

The same problem is occurring with Plexiglas as well, but not as bad. Does anyone had this experience as well and knows a good way of cleaning the heads after?

We think that we do know where the problem is coming from, but there is not really a solution since we are talking about a static charge of the material and we are using a ionizer already. Not the mimaki “build-in” offered with the machine (4500 is a rip-off), but a good stand alone solution. Mimaki is not really able to help so far and the forums in Germany are not really that specialized.

Thanks for any answers …

 

[lubo1972]

Did you try cleaning sheets with isopropyl alcohol before printing? If you cut plexiglass with laser you can't use osopropyl because it will get cracks.

 

[NP K]

Hello Samnas,
it also could be that you get reflections from your jig or material to the printhead. In this case, your ink gets hard on the printhead and clogs the nozzles.
Just check this with printing on darker material.

Good luck! Greets
NP K

 

[TA04]

Hello, for this problem have the function "refresh". Look in manual, exactly tell this.

 

[Marac]

Hello , i am working on ujf60-42 mkII . Had same problem with clear and primer . Did you try different resolutions ( on ujf 600x600 or for base clear printing, different % of amount of clear ) Materials want to deform under UV lamp too (then mist is problem ). Did you check dishway wash , nozzle wash?