To build exceptionally effective extrusion dies, this shop brings together strengths in three key areas: CNC machining, EDMing and tool room operations.

Unless you are in the middle of a forest, it's hard to look around and not see something made of extruded plastic--the siding on a house, the trim on a car, the frame of a window sash. And even if you are in the middle of a forest, the trees you see are the source of a key ingredient in many of the most advanced and complex extruded products--wood. Wood fiber and wood flours are blended with plastic resin and extruded to make a wide variety of products such as deck planking, hand rails and architectural trim. To add to the growing use of plastic extrusions, emerging techniques allow materials to be extruded as foam and encapsulated in an outer layer that is rigid and weather resistant. Shapes with hollow cross sections in complex configurations are also possible.
CPC Tooling's strategy for meeting this challenge is based on a simple concept. The company must be able to build tooling not only for customers pioneering new applications, but also for customers whose conventional applications require faster running, longer wearing, more flexible and economical tooling. In-line tooling that turns extrusions into finished pieces ready for shipping is one of the shop's specialties.

All For One, One For All

"Designing and building extrusion dies is as much an art as it is science," declares Bob White, tooling manager at CPC Tooling. Mr. White, who has overall responsibility for the production of extrusion dies and related hardware for forming and cooling extrusions, explains: "You have to understand how material behaves as it undergoes the extrusion process and then use that knowledge to design a die and the tooling that goes with it. And you have to understand all of the machining processes that enable you to build that tooling."

At CPC Tooling, those machining processes are available in three key areas, each located in its own facility within the sprawling Crane Plastics plant in Columbus, Ohio. Each one of those areas must be efficient and productive. Each must leverage the capabilities of the other two areas. Each must keep up with current techniques and equipment.

The CNC machining area is anchored by two vertical machining centers. These machines do the three-axis milling of complex die contours often referred to as coat hangers because of their distinctive spreading triangle shape, as well as two-axis milling of tool and die components.

The EDM (electrical discharge machining) area features one ram and six wire machines, whose ability to cut steep tapers in four axes is essential to the extrusion process, which converts material from a simple shape to a complex one. Wire cutting replaceable inserts, which greatly extend the life of a tooling system, is another critical job for this area.

A staff of skilled tool and die makers supplies all of the components that allow dies and other hardware to be assembled into a working system. Two toolroom areas equipped with precision mills, lathes and grinders provide the flexibility and expertise to build, troubleshoot and repair almost any die or tooling that comes their way.

"Every one of these areas is important," stresses Mr. White. "Each one is vital to our strategy. Yet each area requires its own management style and has its own technology needs," he says.

Capable And Productive

CNC machining has proven to be a key asset to CPC Tooling. CNC machining is both capable and productive. It is "capable" because it allows complex die contours to be machined in 3D. It is "productive" because it allows 2D work to be handled on a production basis, with pallet changers and shopfloor programming to keep the machine fully occupied.