Question about Kroy K 4350 Printer

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Need help with Kroy K4350 Printer.

Hi,I have a Kroy 4350 Printer we use for printing on heat shrink tubing. Recently it has been printing stray lines on the center and sides of the tubing. We cleaned the head etc. Nothing works. Please Help.

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  • clyde549 May 27, 2008

    I started having the same problem with my Kroy K4350. The black streaks print down the middle if the heat shrink tubing. They seem to appear and disappear completely at random. It is aggravating.

  • Anonymous Jun 21, 2008

    I have the same problem :( Could you help us ASAP?


  • Anonymous Jun 21, 2008

    I have the same problem.

    I worked with all size of heat shrink and sticker.

    Do you think it was print head problem?

    I tried to clean print head but it didn't work.



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It's definitely a fried pixel on the print head. There are several causes.

1) Running the print head too hot (i.e. at max heat).
2) re-using the ribbon can place dirt and/or static at the printhead.
3) Using un-flattened heat shrink will also cause premature failure of the printhead.

We have been selling the K4350 for a few years and always tell customers to use tubing that's as flat as possible. We specialize in printing on heat shrink, so feel free to call us. We'll even buy back your Kroy printer if you want to upgrade to a higher output printer

Posted on Jan 15, 2009

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I have had to replace the print head several times. However, under Kroy's warranty, I only had to pay for the new head once.

I have tried the new hybrid ribbon that Hanover Tech has recommended. And to this point, the new print head in conjuction with the new hybrid ribbon from Hanover Tech, I have had no black steaks! For several months now! Our machine runs daily. We feed miles of heat shrink tubing through it.

Hanover Tech is a top notch company. If you need help, call them and ask for Don (the owner). You may be surprised that you will get better tech support from him then from Kroy! Also, the new hybrid ribbon is not available direct from Kroy. You'll have to purchase it from Hanover Technical.

We also run an ionizer over the heat shrink tubing before it enters the back of the printer. This, to help illiminate any static charge. In my opinion, the sudden static discharge is what is zapping the pixels.

Posted on Oct 03, 2008

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This sounds like a hot pixel failure on the print head. The hot pixels are not repairable. The entire head will have to be replaced, most likely, at a cost of about $300. Hanover Technical Sales, Inc. (that's us) does Technical Support for Kroy printers, so we know what we're talking about.

Could it be something else? Sure, but without a pic of the issue, we'd not be able to guess what else it might be.

Make sure that heat shrink tube is clean and free of static electricity. When possible, use Kroy brand tube in the K4350. And we have a new hybrid ribbon that minimizes static at the head ... and consequently minimizes hot pixel issues.

Posted on Oct 03, 2008

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1 Answer

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It appears that your printer has the cut bit set to cut, from a prior print job. Suggest that you do a short print job with the cutter set to NOT cut. That should change the instruction in the machine until it has been changed to cut again. By the way, the factory advises us that the K4350 should typically NOT be using the cutter to cut heat shrink. So you may want to change the setting to NOT cut for the long haul. If this does not solve your problem, you might give us a call. We're Hanover Technical Sales, Inc. We're a premier Kroy Dealer. Call (757) 357-2677 and ask for Don.

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Power off. Firmly hold down the Pause Button.
When the label material starts to feed, Release the Pause button.

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