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  • LEJ 640 UV hybrid issue strange print

    Posted by Anonymous on January 29, 2019 at 12:17 pm

    Hi.

    Just been having some issues with the LEJ 640 hybrid, when it prints it creates some kind of shade over the prints, please see attachments.

    Any idea what could be the cause ?

    I have just went to the service mode and done all the alignments to the print head as it was a bit off, but the problem does not look like it is to do withe alignment of heads. ?


    Attachments:

    Deleted User replied 3 years, 3 months ago 4 Members · 12 Replies
  • 12 Replies
  • A.Kordowski Andy Kordowski

    Member
    January 29, 2019 at 1:54 pm

    Is this the first time you’ve printed on this substrate?

    Ive had this problem before Could be a couple of things, possibly static? or not an approved uv substrate.

  • Deleted User

    Deleted User
    January 29, 2019 at 1:56 pm

    Hi.

    No I have printed on this earlier but same issue regardless of the substrate, In the image one is correx and one is foamex. Not had this issue before printing on both, but then I am novice in this machine, as I mainly used to operate just solvent before.

  • A.Kordowski Andy Kordowski

    Member
    January 29, 2019 at 2:04 pm

    Is there anti static bars on the machine? if there are turn them off that might help. Or it could possibly be the substrate i used to buy from a certain supplier and even though they said the substrate was uv approved it gave these results. I started to buy from perspex and they supply an antistatic and uv board approved in foamex and correx.

  • Deleted User

    Deleted User
    January 29, 2019 at 3:23 pm

    Q: Is there anti static bars on the machine?
    A: Not that I know, there is a bar on the table that has to be dropped on the substrate but that is all in terms of any bar but I think is more to do just keeping the substrate flat.

    I tried on a Correx that was purchased from MDP supplies and also from Europoint both giving the same issue. I am not sure although I think it could be the case but I have used this material earlier from them and was no such a problem before just today its all downhill.

    hym…. Nozzles are no longer in perfect shape as mainly are deflected but I don’t think deflected nozzles would be giving such a issue on a print.

  • Colin Crabb

    Member
    January 29, 2019 at 3:39 pm

    Just check under the head assembly for any fine hairs etc that could be dragging while putting down ink, you never know!

  • Deleted User

    Deleted User
    January 29, 2019 at 3:54 pm

    Already did, cleaned it and all but this does not look like a strike on the media, I am more to do with the static charge and so on, this is something I am my head is around towards. Another problem is that its quite cold at the unit nothing close to the temp required on the printed and there is actually heater underneath the printer (where the temp sensor is) to cheat so a machine can be switched on but overal at the unit its probably around 15 C. But hence I think there is a fair of static charge build up, this "overspray/marks" as seen is quite far away from the print area, like it goes away even 4 cm away where the print should be done given in some trials. According to the manual static builds up more in cold conditions but then same conditions were for over last few months and not had and also had a heater underneath a printer to cheat/lie to the sensor so a machine can be used and run.

    Looks like will be sleeping at the unit today trying to sort this out and doing tests, so open to any suggestions.

  • Deleted User

    Deleted User
    January 29, 2019 at 6:44 pm

    Does anybody have a service manual for the LEJ 640 hybrid ?

    Thanks

  • Deleted User

    Deleted User
    January 29, 2019 at 7:30 pm

    I know where the issue is coming from for sure now. Thanks to Andy Kordowski for pointing me in the right direction, its a static charge that builds up as from the research I made it looks nearly the same as what I am gettting.

    Found this great example.

    http://elektrostatyka.com/userfiles/med … _iss_3.pdf

    and here is a photo of one of the boards which nearly looks identical and I have couple more that are the same as in the link about the static charge

    https://photos.app.goo.gl/dMbtKgYQKvmAEQbH7

    Well I guess its time to quickly find a Anti-Static Ionising Bars and order that, as always it will probably be not cheap.

  • A.Kordowski Andy Kordowski

    Member
    January 30, 2019 at 8:57 am

    Morning Mariusz,

    If it was me before you try and source some anti static bars buy some antistatic sheets from Perspex they do a foamex called Palfoam which is an antistatic sheet. Id give Fraser a call about your antistatic bars thats where i bought mine. Hope you sort this out…cheers

  • Stafford Cox Stafford Cox

    Member
    January 30, 2019 at 8:36 pm

    Have you tried lowering the head height?

  • Deleted User

    Deleted User
    January 31, 2019 at 8:15 am

    Hi.

    It was not an issue with the head height, defo static, Yesterday I purchase from a local place a anti static bar, they had last one in stock mounted it above the media feed and it nearly fixed all the problem, Just tiny left but not the level that customers would complain. I will still give a fraser a call see the prices and may return the unit I purchased as I think its not too good or powerful but unless fraser is really expensive then I will stay with what I got as paid £900 for the unit I purchased.

  • Deleted User

    Deleted User
    February 1, 2019 at 6:58 pm

    Ordered an anti static bar from Fraser so when it arrives finger crossed it will completely eliminate the issue.