Repair large edge chips with epoxy. Application of a little 5-min epoxy to fill in large edge chips can help reduce ink slinging in the press. While only a temporary solution, it can help extend anilox service life. It is important, however, to sand the hardened epoxy so that it follows the contours of the roll surface and does not stick up higher than the surrounding ceramic surfaces.

Remove metal scraps and other defects with transparent tape. Clear transparent tape rubbed over an area of embedded debris will often pick up some of the debris in the adhesive. Materials removed from the cells is often visible in the clear tape. Tape should be applied to the roll surface and removed with a quick jerking action. Fresh tape should be applied at slightly different angles and removed in a similar fashion. The procedure should be repeated until the debris is significantly removed.

Specify stainless-steel collars on new and resurfaced anilox rolls. Stainless-steel collars provide impact protection for the edge of the ceramic and help protect the edges of the ceramic surface from chipping. Collars also encapsulate the ceramic on both ends and help prevent the ceramic from being undercut. Changing out anilox rolls is notoriously difficult with some press models. Because of the difficulty in changing out rolls and especially with solid-core anilox rolls, you stand a good chance of chipping the edges of the ceramic during roll installations and removals. Collars can be used in conjunction with unengraved bands. They can be installed on new rolls or when used rolls are resurfaced.

Monitor bearings for wear. Sloppy, loose, or poorly fitting bearings can not maintain proper position of the anilox and other rolls as they rotate during a press run. This can cause inconsistent impression due to the rolls wobbling in the press. Bearings should be replaced when they start to wear. To save money, apply new bearings to high-linecount process rolls and re-use the old bearings on the lower-linecount rolls.

Stamp out old linecount, volume, and serial number information on anilox rolls. Rolls that have been resurfaced repeatedly often have been stamped with more than one linecount, volume, and serial number. Stamping out the old information helps to avoid confusion about the current engraving specifications.

Specify on orders to have the roll stamped on the non-bearing long journal surface or laser-etched into unengraved bands. Significant ink buildup and wear to the sides of the roll face can render the serial number and linecount data unreadable. Although journal surfaces can also wear or become damaged, these surfaces generally are in better condition than the roll sides and provide a longer-term solution to roll identification.

Standardize the anilox-roll inventory as much as possible. Consistency and repeatability of print results are inherently tied to anilox specs. The easiest way to insure consistency is to order rolls of like specifications—i.e., all 800-LPI rolls should be engraved to the same volume and same angle.

Whenever possible, phase out heavy, solid-core rolls with lightweight, hollow-core rolls as they need resurfacing. Solid rolls are difficult to handle, prone to damage, and present more of a safety hazard to employees.

Excerpted from Common-Sense Flexography: A User's Guide to Improved Pressroom Productivity, © 2007, Printing Industries of America/Graphic Arts Technical Foundation. Used with permission. All rights reserved. Full book is available for purchase from PIA/GATFPress at www.gain.net or by calling 866/855-4283.