Printing and finishing equipment are hugely important elements in today's sign shops. But if that equipment isn’t properly maintained, there can be disruptions in production workflow and a shop owner could lose money very quickly.
Following proper equipment maintenance schedules is key to keeping your business running smoothly. Such is the case with film laminators. Like all the equipment in your business they need to be maintained to ensure that they run at optimal efficiency.
Most laminator manufacturers highlight in their manuals regular maintenance instructions and intervals, which include regular cleaning of all parts. A well-maintained laminator can help save money and avoid problems in the long run.
To help shed some light on this, we spoke to some experts in this area and compiled some tips to properly clean and maintain your roll laminators that will not only help you keep producing high-quality products but also ensure that consistent finishing production processes are met.
Dan Kane, marketing manager for the graphics department at Royal Sovereign, Rockley, New Jersey, says one of the key strategies for keeping all types of shop laminators running in tip-top condition is make sure you don't neglect your finishing equipment. He says that during long periods of inactivity, you should leave the nip in the open position to prevent any prolonged pressure in one specific spot of the rollers. “Failure to do so could result in ‘flat spots’ and during the lamination process you may see areas of uneven pressure. When using thermal laminators, it is a good idea to clean off any built up adhesive that may have ‘wicked’ out during the lamination process. This is especially important if you were to move to a larger width of film then there would be uneven pressure in the areas were the adhesive built up,” he explains.
“Most importantly keep sharp objects away from the rollers, it goes without saying that any puncture or cuts in the roller will have an adverse effect on the lamination process,” Kane adds.
Using Some Good Common Sense
“One of the best strategies for keeping shop laminators in top working condition may be some good old common sense,” says Dan Haan, general manager, Advanced Greig Laminators (AGL) Deforest, Wisconsin. He says it's good to do periodic visual inspections of the nip roll coverings for cuts and dings. He also suggests to open and close the nip rollers to insure that they are opening and closing evenly. “Do a periodic nip impression or inspect the nip rolls for proper zeroing periodically. If the laminator is making funny noises or doing strange things, investigate before these anomalies become a roadblock in your production,” he explains.
“Your laminator is a tool that will either allow you to enhance the value of a printed piece of material ... or, it will give you the opportunity to wad the printed piece up and throw it in the dumpster and start over. Periodic maintenance will keep your laminator as the dependable profit center it is intended to be,” he adds.
Good Laminating Procedures
Haan points out that having a clear understanding of the laminator and its function as well as a clear understanding of the lamination process required will go a long way in preventing premature wear and tear on your equipment. “Understanding that a wrinkle in the film may be caused by a bad thread up by the operator and needs to be started over, verses an over-tensioning condition on the laminator to try and make the problem go away. Proper diagnosis of issues will prevent unneeded wear on the laminator. Having an understanding that if your material is constantly tracking to one side of the machine or the other, that might be a zero setting issue rather than a need to increase the nip pressure. This will also prevent unneeded wear and tear on the laminator.
“Many operators struggle with the laminating process itself or struggle with a piece of laminating equipment because they just don't understand the tasks at hand," he continues. "Investing in proper operator training in print finishing will go a long way in extending the life of your laminator as well as maximizing the profits of your laminating services.”
Keep a Clean Shop, Take Anti-Static Measures
Brian Gibson, wide format graphics specialist for GBC/ACCO Brands, Mississauga Ontario, says that maintaining a clean lamination department is key. “Laminates generate a static field when being unrolled. This turns the film roll into a dust magnet.”
Employing anti-static measures is the answer, he says. Rubber mats on floor for personal protection are a nice solution. It’s also important to maintain a relative humidity of 45 percent (45 percent assists in the discharging of static during dry winter months). This also is beneficial for the printer's printheads as well (static will spread the ink drops). Use an air cleaner with an ion discharger near the laminator. Ions counteract static. Lastly, seal and slightly pressurize the room where your laminator is located. An HVAC specialist can help as well. Incoming air should be filtered for dust. This way all the dust is traveling out of the room versus into it,” Gibson explains.
To Web or Un-Web: That is the Question
Nate Goodman, product manager at Drytac, Richmond, Virginia, states that implementing proper laminating procedures, such as how to web and un-web the machine, can save time and prevent material waste and damage to the machine. “If the nip height for the substrate is set incorrectly or the edges of the board are not cleanly cut, the roller can be damaged by the edge of the board or the rubber can be compressed due to too much pressure. Avoid using too much tension on the supply shafts to prevent undue wear on the mechanism, chain, sprockets, and drive motor. To prevent cuts to the rollers or infeed/outfeed tables, use an enclosed blade when cutting media. Doing so will eliminate any possible imperfections in the finished piece,” he explains.
Some Common Issues and How to Avoid Them
Occasionally issues do arise, and one of the most common they find with a laminator is that the nip roll assemblies get out of alignment or are not properly “Zeroed”, says Haan, who points out that this will cause web handling issues such as wrinkles or bubbles in the laminating films and result in expensive redoes along the way.
“Determining whether or not a nip-zero adjustment is needed can be done a couple ways," he says. "One method would be to use two .001-inch feeler gauges combined with a simple pull test. Place a feeler gauge on each side of the nip roll three inches in from each side and close the rolls onto the feeler gauges. The goal is to have the feeler gauges pull from the nip roll with the same amount of resistance on the feeler gauge. Figure approximately two to four pounds of resistance on each feeler gauge. Most laminators will have a mechanical adjustment assembly which should allow you to make the necessary adjustments to the machine,” he says.
Haan adds a second way to inspect the nip for a proper zero setting with hot laminators is by using two pieces of thermally activated adhesive coated films. “The objective is to have a nip impression that is the same width from side to side. If the nip impression is narrower or wider on one end than the other, you will need to make the appropriate nip adjustment.”
Kane reports that depending on how nip pressure is regulated (mechanical or pneumatic) over time you may see a certain area of the rollers exert more pressure than another. “Should this occur, then despite your best efforts you will be unable to run film or media straight, and you will notice wrinkling or skewing. If this happens it will be vital to adjust the pressure across the nip so there is even pressure.
Additionally any brake or tension systems in the machine should be monitored and not tightened to the extremes, this will help to prevent any undue burden to the motor,” he says.
When to the Replace Main Rollers?
During the life of a laminator, the main rollers will need to be replaced. Over time, the silicon of the rollers do harden, compresses, and becomes glossy. Gibson says rollers wear prematurely. Common causes of premature wear include over-pressurizing the nip believing the laminate will form a stronger bond. “Use just enough pressure on the pressure roller, to smoothly lay film on the print media. It's also a good idea to move your film around the application area on the machine every time you laminate, never laminating in the exact same place twice,” he adds.
You'll know they need replacing, when “The rollers no longer have an even consistency across the surface and are not be able to effectively wet out the adhesive of the films,” explains Goodman. “Additionally, it is important to replace the rollers when an operator mistakenly uses a razor blade or utility knife too close to the rollers and leaves cuts in its surface. The rollers are the backbone of the machine so if they are not in good condition, then the quality of the output will be affected,” he adds.
He says there are three different types of lifting systems used on laminators—electronic, manual and pneumatic. Each type needs to be maintained with grease or oil and have adjustments made to ensure the left and right side of the machine apply the correct amount of pressure.
Look for Artifacts
Haan says that typically it's time to replace your nip roller assemblies as soon as the cuts, dings and areas of missing silicone start leaving artifacts in your finished product.
“A compression set in your nip rollers will also have a profound impact on your laminating process," he says. "A compression set is a permanent impression that occurs in a roller covering that is typically caused by running rigid sub straights in one specific area of the roll under high nipping pressures. A compression set in a specific work area will prevent you from processing materials that are wider than the compression set area.
"Once a compression set is identified, it is time to replace the affected roller, which may include the top and bottom roller assemblies,” Haan says.
Keeping Pneumatic Systems Clean
Haan adds that keeping your pneumatic system clean is also critical in maintaining proper operation of your pneumatic components. “A ‘filter/dryer’ mounted directly on the air intake for the machine is highly recommended. Many operations will have a filter/dryer at the air compressor itself. However this will not properly treat the air flowing from the compressor to the laminator’s location. Some of these scenarios could involve hundreds of feet of air lines collecting moisture from condensation along the way, which will ultimately infect the air system of the laminator,” he concludes.