HIGH-TECH BODY
Most aluminum space frame vehicles use nut inserts paired with shims or washers to tailor the fitment of each body panel. However, the Ford GT team developed a novel new method, called a “plus-nut,” to efficiently join the body and frame, as well as locate the body panels in the proper position relative to the space frame. These fasteners are essentially aluminum nut inserts, with additional machining stock on the mating surface.While machining the suspension and engine mounts, Computer Numeric Controlled (CNC) milling accurately trims each aluminum plus-nut for precise body positioning. The patent-pending fasteners eliminate the need for shimming the body, reducing assembly costs and improving panel fit. The aluminum body panels themselves are also fairly advanced, manufactured using super plastic forming (SPF). “Super plastic forming is fairly new for the industry,” says Bill Clarke, Ford GT body structure supervisor.
“It was a critical factor in producing the large sections, complex shapes and delicate accent lines of the concept vehicle. Large, intricate panels like the cantilevered doors simply would not have been feasible with traditional stampings.
”Rather than using a matched metal die to stamp the body panels, super plastic forming works by heating an aluminum panel to temperatures near 950 degrees fahrenheit (approximately 500 degrees celsius), then using high-pressure air to plastically form the aluminum panel over a single-sided die. This process produces complex shapes not possible with conventional stamping and reduces tooling costs since only a single-sided die is required. According to Clarke, the super plastic forming also reduced production complexity. “As an example, with super plastic forming we were able make the exterior of the rear clamshell in one piece,” he says. “The same panel with traditional manufacturing would require five or six separate stampings joined together on the assembly line.”
The rear clamshell engine cover also represents another industry first: It features an aluminum shell hemmed to a carbon-fiber inner panel. The carbon-fiber piece is lightweight and extremely rigid, which helps stabilize the clamshell. In addition, the inner panel houses an air duct into the engine air box from the exterior intake just below the C-pillar.
-Credit to an article on Modular Powerhouse.
Most aluminum space frame vehicles use nut inserts paired with shims or washers to tailor the fitment of each body panel. However, the Ford GT team developed a novel new method, called a “plus-nut,” to efficiently join the body and frame, as well as locate the body panels in the proper position relative to the space frame. These fasteners are essentially aluminum nut inserts, with additional machining stock on the mating surface.While machining the suspension and engine mounts, Computer Numeric Controlled (CNC) milling accurately trims each aluminum plus-nut for precise body positioning. The patent-pending fasteners eliminate the need for shimming the body, reducing assembly costs and improving panel fit. The aluminum body panels themselves are also fairly advanced, manufactured using super plastic forming (SPF). “Super plastic forming is fairly new for the industry,” says Bill Clarke, Ford GT body structure supervisor.
“It was a critical factor in producing the large sections, complex shapes and delicate accent lines of the concept vehicle. Large, intricate panels like the cantilevered doors simply would not have been feasible with traditional stampings.
”Rather than using a matched metal die to stamp the body panels, super plastic forming works by heating an aluminum panel to temperatures near 950 degrees fahrenheit (approximately 500 degrees celsius), then using high-pressure air to plastically form the aluminum panel over a single-sided die. This process produces complex shapes not possible with conventional stamping and reduces tooling costs since only a single-sided die is required. According to Clarke, the super plastic forming also reduced production complexity. “As an example, with super plastic forming we were able make the exterior of the rear clamshell in one piece,” he says. “The same panel with traditional manufacturing would require five or six separate stampings joined together on the assembly line.”
The rear clamshell engine cover also represents another industry first: It features an aluminum shell hemmed to a carbon-fiber inner panel. The carbon-fiber piece is lightweight and extremely rigid, which helps stabilize the clamshell. In addition, the inner panel houses an air duct into the engine air box from the exterior intake just below the C-pillar.
-Credit to an article on Modular Powerhouse.
