With the turn of a key Bart Gaffney unlocks a door to a showroom that contains tidy stacks of set-up corrugated and fiberboard boxes and displays. These brightly decorated containers serve as examples of what's manufactured and printed at the Milwaukee plant of Longview WA-based Longview Fibre Co. Longview customers use these containers to market protect and transport everything from beer and beverages to produce toys and computer software. The beauty of these containers is much more than skin deep. In fact the real beauty is beneath the printed surface where the fluting is bonded to the liner. Gaffney sales manager for the Milwaukee plant demonstrates by handing this editor two flat pieces of unprinted single-wall corrugated board. One piece reveals lines or marks caused by the pressure roll that's traditionally used to bond the medium to the linerboard to produce single-face corrugated. The other piece of board is virtually free of these marks. Wiping a hand across it reveals the latter's surface is considerably smoother. Traditionally medium and liner webs are nipped at a single point between large cylindrical pressure rolls made of steel. The pressure from these rolls on the two material webs combined with the use of a cornstarch-based adhesive creates the single-face board by bonding fluted medium to the liner. Trouble is that single pressure point can take its toll on the material. "What you often see as a result of this process are pressure marks on the board" says Gaffney "particularly with the lighter-weight boards and microflutes that customers are requesting more and more often. This is something that happens throughout the industry. It's bad because these marks represent areas of weakness that affect stacking strength flat crush and printability." In an effort to eliminate pressure marks the Milwaukee plant replaced its previous single-facing equipment with two MHIPaser Model 60G extended nip fingerless single facers from MHI Corrugating Machinery (Hunt Valley MD). Last year the Milwaukee plant joined all of Longview's plants nationwide to add the equipment.