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HickeysHickeys are imperfections that appear on printed pages due to particles sticking to the blanket or plate. These flaws typically show up as dots with rings around them or as blank spots surrounded by print. If not managed, they can cause significant waste.Causes: These imperfections can arise from unground pigment or foreign substances in the ink, dried ink skin in the fountain, paper dust, or issues with the papers surface. Dust in the pressroom environment or deteriorating rollers can also contribute.Suggestions: To address hickeys, use adhesive tape to remove the particle from the blanket and examine it. If the issue is with the ink, consider changing it or cleaning the ink fountain. If it%u2019s related to paper fibers, reduce the ink%u2019s tackiness. Regularly inspect roller conditions and use a hickey picker roller. In some cases, switching to a different paper may be necessary.DustDust particles on the paper surface can transfer to the blanket, resulting in dark specks or voids in the print.Causes: Dust accumulation can occur during sheeting or trimming operations.Suggestions: Pre-dusting with a dry, blank unit can help. Inspect the edges of the paper for cut quality and wipe them with a glycerine or tack cloth. Trimming the paper on all sides or using a different batch of paper may also resolve the issue.PilingPiling occurs when ink builds up on the blanket, rollers, or plate, eventually leading to a loss of image detail or pulling fibres from the sheet. This defect can appear as patchy print or missing areas and is often more visible in solid areas.Causes: Piling can be caused by defective paper coating, improper fountain solution mix, ink that has absorbed too much water, or ink drying too quickly on the press. Other factors include improperly packed cylinders, worn rollers, or overly tacky blankets.Suggestions: To address piling, consider using a lower tack ink, adjusting the dampener settings, or changing the ink. Ensure cylinders are properly adjusted and consider treating or changing the blanket. Regular clean-up and maintaining a good ink/water balance are essential. If necessary, adjust the printing sequence or speed to reduce interaction between the sheet and the blanket.GhostingRefers to an unintended reproduction of faint images or patterns on the printed surface, which can negatively impact the quality of the final output.Causes: This issue can stem from poor job layout, a thin ink film, transparent ink, or worn ink rollers.Suggestions: Improving job layout and consulting with the ink manufacturer can help. Consider using heavier ink films or reformulating the ink for better opacity. Regular maintenance of rollers is crucial, including using the right cleaning agents and replacing worn rollers to prevent ghosting.Misregistration / SlurMisregistration or slur occurs when the printing dots don%u2019t align correctly, resulting in a blurred image or colour variations. Register marks may also be misaligned.Causes: This problem can result from gripper slip, loose blankets, high ink tack, feed table misalignment, or issues with the papers edges or quality.Suggestions: Adjusting and cleaning the grippers, ensuring blankets are properly torqued, and lowering ink tack can help. Check the feed table alignment, reduce impression squeeze, and inspect the sheets for wavy or tight edges. Trying a different paper batch may also resolve the issue.Blocking / OffsettingBlocking or offsetting happens when ink transfers to the back of the next sheet, sometimes causing the sheets to stick together.Causes: Insufficient spray powder, overly high delivery stacks, excessive ink film, slow-drying ink, or an imbalance in ink and water, combined with humidity, can lead to this issue.Suggestions: Increasing or changing spray powder, lowering the height of the delivery stack, and adjusting the ink/water balance can help. Consider using more pigmented ink and reduce ink film for better results.Baggy RollsA baggy roll refers to a roll of paper with uneven tension across the web, usually caused by a soft or loosely wound edge or center.Suggestions: Increasing web tension, repositioning suspect rolls, or isolating rolls based on their hardness profile can improve consistency. Running rolls in consecutive order can also reduce variability.Board Delamination With Rolling Up / SkinningDelamination appears as one of the paperboard layers rolling up, typically at the edges of the sheet. This defect can lead to severe damage, such as blanket smashing.Causes: This issue arises from a defective cut of the last sheet in the board block and the displacement of sheets during the guillotining process. Both factors contribute to delamination and subsequent rolling. Friction between the edges of the paperboard blocks during handling or manual loading of the printer can also exacerbate the problem.Suggestions: Check the guillotine machine%u2019s ribbon for wear or deformation and consider replacement if necessary. Regularly monitor the quality of cuts with a magnifying glass. Minimize handling of paperboard before printing and take precautions to prevent friction between blocks during handling.21