As the highest-volume car builder in the world, Mattel’s Hot Wheels brand dedicates huge resources to the design of its products. So far, the company has developed 800 models with total production of more than 4 billion cars since 1968.
Despite recent advances in digital design tools, these 1/64th-scale replicas of production cars still require the human touch to reach fruition, reports Felix Holst, Vice President of Design for Hot Wheels.
CAD tools have enabled significant advances from the days of Holst’s arrival at Mattel as a new designer in 1996, so that human touch isn’t quite as labor-intensive as it used to be. For his first assignment, Englishman Holst was dispatched to visit English specialty car maker TVR to document the measurements of its Speed 12 concept car for translation into a 1/18th-scale model.
He worked in the company’s parking lot, using the traditional tools of the trade: a tape measure, spirit level, and post to record the car’s dimensions. “It was a handmade prototype and there was no symmetry in the car whatsoever,” Holst recalled. “It took 10 hours because I had to measure every data point on the car.”
Since 2004, however, Mattel has received digital CAD files describing new cars it replicates. “You would think in this modern age of digital design that our job got a lot easier in the last decade,” Holst explained. “And we thought it would.”
Naturally, it didn’t turn out to be as simple as it seemed. “When [OEMs] started telling us they could send us CAD files, we thought, ‘Great, get the shrinking machine out!’ We would just manipulate those files and we would end up with toy cars and we would have such efficiencies,” Holst chuckled.
But reality intruded. “It doesn’t work like that because when you shrink a car, a lot of the proportions that work when it is full size change completely. They tend to get very skinny. Sometimes the glasshouse can get too tall or too low. The wheels can get very small. The whole thing falls apart aesthetically,” he said.
So Hot Wheels designers use the digital data as the starting point for their own designs. “If you don’t, you end up like Matchbox cars looked in 1961. Very pure replicas with tiny wheels that are very long and skinny.”
In addition to enlarging the windows and wheels, designers have to adjust the wheelbase of the car to match the car being replicated. The 50% of Hot Wheels cars that are original designs, rather than replicas, use a standardized wheelbase for production efficiencies.
To achieve the right appearance for Hot Wheels, some designers still sketch out designs by hand. Others use Geomagic Freeform 3-D modeling software to design the sheetmetal.
Once the designs are in digital form, Adobe Photoshop is a valuable tool for editing, said Holst. “Everything is in Photoshop, which has become a massive aid for the designers,” he said. “Photoshop lets us make changes to designs incredibly quickly.”
From there, Hot Wheels turns to a rapid prototyping 3-D printer to produce the model overnight. “There is no substitute for being able to look at the car in 3 inches and hold it in your hand to make sure everything is correct,” Holst explained.
When that design is finally approved, designers export the image in Dassault Systemes SolidWorks CAD software for the plant to manufacture the casting dies using three-axis CNC machines. When the die emerges from the CNC machine, a designer who has been sent to oversee it hand-finishes the die, cleaning flash from the part lines and otherwise perfecting the final result.
“We go through this high-tech process to get to that point, but then there is no substitute for hand-finishing,” Holst noted.
Indeed, the strong human element throughout the design process is the opposite of expectations once digital design files became available from car makers. “It was probably far more shocking to accountants than it was to designers,” he said.
“We pride ourselves in how much passion goes into the designs we create,” Holst continued, so designers understood that digital files were a starting point, not a final product. “The old hands said, ‘I knew that was gonna happen,’” Holst laughed. “They couldn’t suddenly get rid of all those pesky designers!”
A recent development has been development of full-size Hot Wheels cars and collaboration with OEMs for production of some of them. The company has built 14 full-size Hot Wheels cars, concepts wearing the exaggerated proportions and huge wheels fans recognize as Hot Wheels under the rubric Hot Wheels for Real.
In 2011 Hot Wheels worked with Chevrolet to build a Camaro for the SEMA Show, a car that replicated the first Hot Wheels Camaro, the Spectraflame Green 1967 Camaro toy. The full-size car was chrome-plated and sprayed in candy apple green clearcoat to achieve a shimmering effect like the metallic paint on the ’67 Hot Wheels car.
But when Chevrolet built a production Hot Wheels Camaro for 2013, it was shot in Kenetic Blue instead. “There’s no way to get that [chrome paint] to happen in production,” acknowledged Dave Ross, Design Manager for General Motors accessories. “It would have made the car impossible to afford.”
“From our side, most of the designers, every one of us, were weaned on Hot Wheels,” said Ross. “We had incredibly high expectations for this project, and it was a lot of fun for all of us. The biggest surprise was that we shared the enthusiasm, energy, and creativity from both ends.”
Apparently there is full-scale enthusiasm at both GM and Mattel, even if Mattel’s designers produce smaller cars.