Expanding capabilities through metrology

EVCO Plastics, a global injection molder based in DeForest, Wisconsin, with plants throughout the U.S., Mexico, and China, has more than 150 presses in the 28- to 3,500-ton range, its own mold production, and a world-class metrology lab for quality evaluation.

To ensure part quality, Metrology Lab Chief Rich Duval says the company must be able to “take a part, scan it, compare it to the CAD/CAM files as early as possible in the process, and allow the customer to observe how the plastic product compares to the solid model.”

By using scanning technology and reverse engineering, the EVCO metrology team has been able to recreate the surface of tooling where solid models don’t exist and provide data to a tool shop for steel revisions.

Metrology expansion

Recently, due to the volume of work coupled with the challenges of collecting and processing point cloud data in the lab, the EVCO team turned to its supplier partner, Exact Metrology in Brookfield, Wisconsin, for assistance. The company had been researching earlier generation scanning, but saw more advanced Romer and other brands of scanning arms in the Exact product offering.

Exact Vice President Dean Solberg says it was important to update equipment and expand metrology capabilities at the company.

One example involved reconstructing the cogs of a damaged tool component on a machine gear. Once rechecked through design, a suitable alternative could be 3D printed. Duval notes, in this way, the metrology solution could reduce inspection time in the lab and provide reverse engineering as an additional option.

Technicians at EVCO are using the new scanning techniques to evaluate older molds for position of runners, pins, cores, and other components. The scans lead to a solid model to show auto-surfacing, solid model processing, and solid model in-use characteristics. Often, the lab technicians reverse engineer solutions from existing parts to resolve production issues or for part validation.

While continuing to use the conventional coordinate measuring machine (CMM) technology in its metrology department, Duval says his team of technicians has been able to marry the Romer arm and CMM technologies. Combining 3D scans with the bridge CMM plates gives the technicians and design engineers the necessary comparative data to resolve issues.

Service and training

Support from the Exact team has aided EVCO during this ramp-up of the new scanning technologies.

“We had some lurking questions after the initial training session, but Dean was very pro-active and amended the training protocol to suit our specific requirements,” Duval says. “It’s produced a very positive outcome here.”

EVCO is routinely expected to supply considerable part and production data to its customers, according to Duval. “We are planning to utilize the Exact equipment to support tooling, so there will be a seamless capture and transmission of data from part design through production.”

Prototyping capabilities

One of the strongest abilities at the company is the production of near-finish prototypes, often produced with conventional CNC machining or through the use of 3D printing technologies. EVCO often uses fused deposition modeling, with and without carbon fiber. Here, the 3D scanning techniques produce the necessary data files, such as STL, that can reside in the point cloud for use by advanced 3D prototype production technologies. Millions of data points provide the 3D printing equipment the necessary information to produce highly accurate prototypes, and it helps engineers anticipate challenges that might arise in the transition from design, to tool, to production, Duval says.

EVCO Plastics

www.evcoplastics.com

Exact Metrology Inc.

www.exactmetrology.com