The Michigan Manufacturing Technology Center last week at SEMA showed off a model of a lightweight aftermarket frame which could provide specialty car designers and owners with what it called “an affordable, stiffer and safer car frame option.”
This technology is clearly of greater interest to the restoration and customization folks, but it’s still worth noting by production collision repairers as another example of the feasibility of mixed-material structural design.
“Although multiple lightweight materials are integrated into the frame’s design, the engineering and design team was able to keep the cost comparable to current production steel frames,” the center wrote in a news release.
The more convenient and cost-effective mixed-material bodies-in-white and exteriors become at the factory level, the more likely it is that a wider skill and tool set will be required for the aftermarket. If OEMs and suppliers can take research like the center’s and run with it, that scenario gets closer to reality.
“This frame uses a holistic design approach that reduces material weight by >30%, uses the most cost effective lightweight materials for each part, eliminates primer/paint, replaces destructive spot welds with high performance and continuous bonds, uses inexpensive tooling and minimizes the number of tools required, is self-fixturing, minimizes the parts count, and is engineered to minimize assembly labor,” the center wrote in an FAQ in response to how the frame could be competitive in price to a steel frame.
The center built a scale model of a 1963-67 C2 Corvette frame which would be 89 pounds lighter but “150 percent stiffer in torsion and 450 percent stiffer in bending than the baseline C2 production frame,” the center wrote. Torsionally, the frame design is stiffer than a Ferrari F430 and Lotus Evora, the organization said.
It’s built out of aluminum, carbon fiber, magnesium and ultra-high-strength steel, according to center marketing manager Jeff Schultz.
“It requires no welding so the parent material is not weakened during assembly and allows for thinner section material, reducing material cost,” the center wrote. “The frame is joined using structural adhesives and mechanical fasteners; the adhesive bonds 100 percent of the flange which spreads the loads out over a larger area than a typical spot weld. This uniformly distributes the forces and reduces local stresses, meaning thinner wall materials, further reducing material weight and cost.”
According to the center, the frame can be customized to fit “fit virtually any body width and length.” It also doesn’t need jig fixtures, as it sports a “self-fixturing design.” The design also factors in crashworthiness; the FAQ notes that it “uses energy absorbing front and rear modules similar to those used on the Lotus Evora and the C7 Corvette to help protect the occupants.”
“The frame’s construction is not only strong and cost-efficient, it’s nearly 90 pounds lighter than the C2 Corvette baseline,” center principal materials engineer Gregg Peterson, Principle Materials Engineer said in a statement. “We look forward to bringing this innovative design to specialty car manufacturers and restorers in the future and showcasing models to industry peers at SEMA this year.”
President Michael Coast said the center took the frame model to SEMA to see how much interest existed in the market. The organization plans to try and commercialize the frame in 2018, he said.
We asked if the center planned to produce repair guidelines for the new frame, which would require far different techniques than any milder-steel frames it’d replace.
“As for ‘repair procedures,’ we haven’t gotten that far yet since the team has been focused on testing, but that’s clearly something to consider down the road,” Schultz wrote.
The Michigan Manufacturing Technology Center’s model C2 frame was designed by the center in conjunction with the Institute for Advanced Composites Manufacturing Innovation (whose members include OEMs), Lightweight Innovations for Tomorrow (whose members include OEM metals suppliers) and the University of Tennessee, Center for Industrial Services Institute for Public Service.
Michigan Manufacturing Technology Center via PR Newswire, Oct. 24, 2017
The Michigan Manufacturing Technology Center last week at SEMA showed off a model of a lightweight aftermarket frame which could provide specialty car designers and owners with “an affordable, stiffer and safer car frame option.” (Provided by Michigan Manufacturing Technology Center)
The Michigan Manufacturing Technology Center last week at SEMA showed off a model of a lightweight aftermarket 1963-67 C2 Corvette frame, right, which is lighter and stiffer than the original steel frame. (Provided by Michigan Manufacturing Technology Center)