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Wide format printing problems and how to deal with them

Engineering and colour combined - Cog coloured in CMYK printhead with ink cartridges printing. Colour optimisation charts.  

Engineering the perfect print

VTS can provide "engineering expertise, optimise colour profiles and supply high quality ink to give you the best possible print".

VTS Ltd was founded in 2009 and specialise in providing warranty packages and repairs for Roland, Mimaki and Mutoh printers. They are based at Holton Heath near Poole and has customers as far north as Newcastle.

Over the last seven years they have seen all sorts of problems with printers.

Some have been easy to fix; some have been expensive and time consuming; and some look like a problem with the printer, but are something completely different, says the company.

VTS tell us about some the most common ones and provide a few tips on how to solve them.

Banding issues

This is the most common reported fault and can be one of the easiest to sort out.

The printer software relies on the printer laying down a regular pattern of ink droplets that will dry before the next set of droplets arrive. This can go wrong if:

  • The heaters are not set correctly
  • The printheads are not laying down the correct pattern due to deflections
  • The calibration for feeding the material is wrong
  • The bi directional and other head settings are wrong
  • The ink is not drying correctly

You may need to get the printer adjusted to correct this, but in most cases it is an adjustment that can be done by the customer.

If you have narrow dark banding lines, check the ink is drying correctly. We have had problems with ink when it gets old. After researching the problem for two years, we have found that 18 months after manufacture inks start to deteriorate. This can cause drying problems; it can also give nozzle deflection which can lead to banding too.

Printing greys

Each printer has its own unique characteristics and may need to be profiled to give the correct colours. Quite often the standard profile will be good enough for most print work, but won't give you a good grey.

The existing profile can be optimised by using special equipment; this looks at all the colours and adjusts them to the correct values. Each media you use needs profiling to give the best results. So far we are only able to offer this service to customers that use Versaworks. Most of the profiles from the leading media manufacturers are very good so try using these. And compare them to the generic profiles supplied with the printer software.

In most cases the standard profiles can be optimised easily to give very good greys.

You can also “tune up” the printer by adjusting the heads and head height to a very fine tolerance, giving the best possible quality.

Alternative inks

We have always been asked what ink to use. OEM is always the best option but can be expensive if you do a lot of printing.

There are several after market inks available on the market, most of which have had very bad press in the past. This has led to most of them having to raise their game.

Most of them now are a viable alternative to the OEM, but be careful. If you are not using the printer very much the cost savings may be small; and make sure it is fully compatible with your printer. Ask around and get some feedback from other users of that brand.

When ink gets old

We started to identify problems where the age of the ink installed in a printer was over 18 months. This included nozzle deflection, white spots and streaks, and poor drying.

This can be a real issue if you are a low volume printer and keeping a lot of stock on the shelf. The cartridges may go out of date before you are able to use them.

After a few problems ourselves, we wanted to find a reliable alternative and asked around.

The Streamline brand came highly recommended, with some very good reports of the quality from the customers using it.

We liked the fact it had a clearly marked use by date; it is made in the UK so there is a short supply chain, giving it a very long shelf life. It's made by Sun Chemical one of the largest manufacturer of ink in the world, and who make inks for a wide variety of brands of printer. It is also Greenguard certified and matched to OEM for colour.

After two years of testing we were confident enough to recommend it to our warranty customers. We wouldn't recommend anything we are not sure of, as we will have to fix any problems that may occur. About 90 per cent of our warranty customers use Streamline ink, and the problems we were getting have dramatically reduced.

Drifting blurred print

This is a common issue on all printers. The printer uses a long encoder strip to measure the distance it has printed on each pass. If there is any dirt or dust on the strip, the printer can get the numbers wrong and will move more or less than it should each pass. This causes the print to wander back and forwards up the sheet, and have a blurred appearance.

Sometimes this can be corrected by wiping the strip with a soft cloth. If this does not help then a special fluid can be used or the strip will need changing. Sometimes the reader that scans the strip can be faulty; this cannot be cleaned and will need to be replaced.

Printhead from a wide format inkjet printer

Check the heads

Quite a few problems may just be due to dirty printheads. Do a nozzle test print (the user’s manual will tell you how to do this). If there are gaps of deflected nozzles, manually clean the head with the correct fluid for the ink you are using and a foam swab. If you are getting drips of ink at the end of each pass there may be a fibre stuck to the head; this may also drag across the print causing small lines. It is usually a good idea to clean around the edge of the heads once a week, this helps to prevent fibres sticking and helps the wipers to work properly.

If everything is adjusted well and you are using good media, a good profile and good ink, the print will as close to perfect as you can get, giving an extra “wow” factor to show your customers.

If you have any issues that you want to talk to us about we will always try and resolve them over the phone. There is no charge for this and quite often it is something simple that does not require a visit. Please This email address is being protected from spambots. You need JavaScript enabled to view it. any pictures that you have showing the problem.

www.vts-service.co.uk

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