Benjamin Franklin’s old adage, “An ounce of prevention is worth a pound of cure” still rings as true today as it did when he wrote it back in the 1730s. It’s fitting that this saying was coined by not only one of our country’s founding fathers, but also by one of the earliest innovators of the American printing industry. Although Franklin was originally discussing fire safety when he penned that famous quotation, that same thinking can also be applied to the care and maintenance of grand-format printers presently in sign shops across the country.
Given the huge investment in this equipment and of possible repairs that might be incurred, it is essential that these models be properly maintained in the field on a regular basis.
When a printer of this size breaks down, production halts—but that doesn't mean the large-volume jobs stop keep coming in. A backup like this can throw a major wrench into a shop’s workflow and can quickly escalate into a plethora of production issues, all of which are in direct conflict with clients' needs, and quickly leads to missed production deadlines, and damage to the bottom line In addition, minor issues and support calls that also arise on a daily basis can also be avoided by implementing a regular preventive maintenance schedule for your equipment.
A Good Starting Point
When implementing a preventive maintenance schedule, the owner’s manual that came with your printer should be your bible and the ideal place to start. “Like any piece of industrial equipment, a little preventive maintenance can go a long way,” says Sean Roberts, global customer experience center manager at EFI in Meredith, New Hampshire. “Grand-format printer manufacturers typically provide in-depth maintenance guides including shift-based, weekly, monthly, and annual procedures for best performance. Within these, two key areas for callout are cleaning for jet faces, capper station, anti-static bars, belts and rollers; and lubrication of rails, carriage drive, winder bearings and media bars."
Roberts adds that grand-format printers are designed for a constant-duty cycle in demanding print environments. “Their design should be more robust than a typical printer (i.e., powerful drive motors and high-precision parts) to ensure sufficient mean time between failure (MBTF) in a continuous cycle environment,” he says.
Keep it Clean
Preventative maintenance starts with keeping printheads, cap station, and wipers clean—basically any area where ink is exposed and can accumulate. It also means keeping the heads wet. Whether it is head washings, nozzle cleanings/wash (this will vary according to printer), run procedures as they are recommended.
Christopher Guyett, sales and marketing coordinator at Durst Image Technology US, Rochester, New York, says like any machine, a UV-cure printer of this size will operate best in a clean, climate-controlled environment.
“By regularly cleaning your printer and the room it resides in, you’re already half way to ensuring trouble-free operation. The other half is preventative maintenance. It’s best to follow a manufacturer-recommended schedule of filter replacements, UV bulb replacement, and other checks—and to address issues as soon as you notice them rather than waiting until they become problems.”
He explains that Durst provides for their customers a service called CORE Visits. “A CORE visit consists of a complete diagnostic check of the printer from a Durst-certified service technician. It includes verifying that all pressure systems and flow rates are up to factory specifications, performing full printhead alignment, and addressing any outstanding issues regarding media transport or image quality.”
Guyett adds that even though the media transport system will be different on a flatbed versus a roll-to-roll printer; the maintenance principles remain the same. “Whether a belt or print plane, keeping your print surface clean, dry and free of debris is important for good media transport – as well as for overall image quality.”
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Stick to the Schedule
“Overall, the success of a printer is greatly affected by the operator or the shop’s ability to follow the maintenance schedule suggested by the press manufacturer,” agrees Becky McConnell, product marketing manager at Fujifilm North America Corporation, Graphic Systems Division, Hanover Park, Illinois.
“Print quality will deteriorate and continue to deteriorate if regular maintenance is not properly performed. The most important area is printheads—with the advancements in printhead technology and the precision that is required to produce the quality demanded, maintaining printheads and keeping them at their optimal performance is required,” she adds.
Stay Within Supplier Guidelines
Tom Giglio, GSB strategic accounts manager for Hewlett-Packard, adds that the most important items are to follow the manufacturer’s guidelines for suggested facility site requirements—workspace allocation, environmental, electrical, etc. He says that once the printer is installed, maintenance schedules should be strictly followed and the printer should be kept clean of any debris, which may have been introduced by substrates.
“It is critical to keep a good work surface by cleaning the table or belt, keeping the UV lenses clean, making sure the print carriage is free of any overspray; and most importantly, keeping the printheads exercised and in optimum working condition,” Giglio says.
Keep Good Records
“It is also important to maintain good records of the UV lamps and hours of usage, as curing energy is very important to successful printing,” Giglio says.
He points out that because UV printers use light to cure the ink and print on a wider range of substrates than a typical roll-to-roll printer, ink adhesion becomes extremely important. Low- (surface) energy substrates like polypropylene and acrylics are especially challenging, so it is very important to have a printer/ink combination that can print successfully onto these types of substrates.
“Some manufacturers have multiple ink sets for different purposes—color density, flexibility, substrate range, ability to machine with a router, etc.—and as a general rule, the higher the color gamut, the less adhesion a particular ink will have. Conversely, inks with higher adhesion characteristics will have less color gamut. It is very important to balance customer requirements for color (gamut) with workflow (routing/cutting/finishing) in choosing the right printer/ink combination. HP Scitex inks are general purpose inks and one of the advantages is that it is compatible with most typical substrates,” he says.
Proper Ink Storage
It is also very important to keep track of the inks you are using as well since UV-cure ink does have a shelf life. Giglio says UV-curable ink is shipped to the end user in bottles, bags or boxes whereby the ink is shielded from ambient UV light.
“It should be stored in a temperature and humidity-controlled environment similar to the printer’s environment,” Giglio says. Ideally inside an ink cabinet, which can be purchased from any industrial supply store. The average shelf life of most digital UV-curable ink is about 12 months. After this period, the ink may be unstable and can underperform. The end user should use a FIFO (First-in-First Out) system when purchasing and consuming ink and also keep track of ink lot numbers from the manufacturer.”
McConnell points out that Fujifilm's Uvijet digital inks feature a shelf life of a year from the date of manufacture. “As far as proper storage, each product’s MSDS (material safety data sheet) will list the proper storage but in most cases, it’s fairly simple. Keep it away from heat and sources of ignition. Keep in properly labeled containers. Keep containers tightly closed in a dry, cool and well-ventilated place. The stability of ink will be compromised if it is stored past the expiration date issued by the ink manufacturer. The consequences of using expired ink could lead to damage to the printheads or the ink system within a press. The down time costs that could be created by using expired ink is far more devastating than the cost of the expired ink,” she says.
Keep a Maintenance Kit Handy
It’s also important that your shop keep certain items on hand in the form of a maintenance kit to ensure that your printers receive adequate care and remain properly maintained. Guyett says a good maintenance kit will include the appropriate printhead cleaning solutions and tools, bearing and rail lubricants, print plane treatments, spare UV lamps and filters related to the specific machine. “Remember, establishing and sticking to a regular maintenance schedule is as important as stocking the correct parts and cleaning products. It is also recommended to always document who performed the maintenance work and when, so you can track issues over time.” ?
Service Contracts a Key
McConnell points out it’s also essential to look at supplier service contracts and programs and the benefits they can offer. “Just like any insurance, service contracts and manufacturer programs are put in place to protect your investment in the event that there is a problem. Benefits of service contracts are the assurance that if there is a problem, immediate expenses can be lower. Another benefit could be discounts on parts and/or consumables that are needed due to everyday wear and tear. In some cases, service contracts offer you more readily available technician support like weekends and holidays, which can prove to be extremely beneficial to some print service providers,” she says.
Giglio says that service contracts are crucial for grand format UV-cure printers because of the many high-technology components, which if they fail, can consume the entire cost of a service contract in a couple of service visits.
“Printheads are at the center of that discussion; some manufacturers attach an allotment of them as part of a service contract, say four per year, while others treat them as consumables that are not included as a part of any service contract. With many of today’s grey scale printheads exceeding $5,000 for just one printhead replacement, the end user should look into the impact of this expense for their total cost of ownership,” he says.