DETROIT -- General Motors is using film rather than paint on parts for five vehicles. Bumper fascia and rocker panels are among the parts involved.
Unlike past users of paint replacement film on parts, GM has chosen a thick thermoformed sheet. The company intends to develop a supply base of thermoformers.
"This is one of our major efforts," said Charles Buehler, a technical integration engineer in GM's materials group, during an Oct. 11 interview at the Society of Plastics Engineers' Thermoplastic Olefin conference in Sterling Heights, Mich. "We're working to build a cooperative supply base for thermoforming."
GM first used a thermoformed sheet that combined a thermoplastic polyolefin base with a body-color film on a stone shield for its Chevrolet SSR pickup. Now the Chevrolet HHR wagon has stone shields that were made using the process.
Two cars just beginning to roll out -- the Buick Lucerne and Cadillac STS-V -- have thermoformed rocker panels; the GMC Envoy will have thermoformed bumper fascia starting next year.
GM and its suppliers have created 1,000 of the fascia in an early rollout. With the bumpers, not only did the companies eliminate the need to paint a plastic part, they also replaced an injection-molded part with thermoforming.
An earlier paint-replacement system that debuted on the Dodge Neon used thermoformed paint replacement, but the fascia was injection molded behind a thin formed sheet.
The thick-sheet thermoforming reduces the number of manufacturing steps, which shortens development time and cuts costs. That's because tooling for thermoforming is less expensive than standard injection-molding tooling, Buehler said.
Using thermoforming, the company and its suppliers can create a component -- from design to tooling to production -- within 120 days, he said.
"We see this as an enabler," Buehler said. "We're not against injection molding behind (the sheet), but we think the supply base in place isn't ready."
Now a supply base for thermoforming is developing, creating opportunities for molders, material suppliers, tool makers and machinery makers.
The GM system uses films produced by Soliant LLC of Lancaster, S.C., that can match the full line of automotive paint colors.
Machinery makers accustomed to making materials-handling equipment are learning how to make parts that meet automakers' demands for Class A surface quality, said Ed Bearse, a partner in Plastic Concepts & Innovations LLC of Mount Pleasant, S.C.
His company helps coordinate communication within the developing supply chain and runs training programs for thermoformers.