Through the years, no materials have caused more nightmares for converters around the world, than the family of products we call, "plastics." The most common types of plastic include: polypropylene, high and low-density polyethylene, polyvinyl chloride, vinyl, and polystyrene.

The properties of plastics that make them so versatile, effective and multi-purpose, are often the exact same properties that make them so difficult to convert. For example; plastics may be flexible, brittle, or stretchable, thin, medium or thick, clear to opaque, really easy to tear, easy to tear, tough to tear, or impossible to tear, have excellent "memory," or have no "memory," react readily to heat, or don't react to heat at all, allow air to pass through them or actually prevent bullets from passing through them. You get the picture. So how do you cut, crease and perforate such incredibly diverse materials?

Cutting plastics with steel rules may often require an extremely sharp, sleek cutting edge. For cutting in "conventional" platen diecutting, a ground edge is strongly recommended over the more popular shaved or skived edge. Not only is the ground edge sharper, its machine lines (grinding lines) run in the exact same direction as the cutting process. The machine lines of a skived edge run in the exact opposite direction of the cutting action. This can cause problems when cutting plastics. A sleek, ground edge may often reduce cutting pressures and produce a cleaner, smoother product edge. There are several rule manufacturers, including Zimmer Industries that make excellent ground edge products.

Reprinted with Permission from Greg Zimmer