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looks and acts like blotting paper with the resin just sitting on the surface." Dodworth continued to work on the problem until he came up with a novel solution: McDonald's drinking straws. "I went into a local McDonald's, grabbed a handful of drinking straws, glued them together with super glue, and chopped them to a uniform thickness," says Dodworth. "We could have used any plastic we wanted, but we wanted one with a fairly high melt temperature, and recycled polycarbonate"—as in the straws—ft the bill." The straws separate the recycled carbon fber skins, connect the top skin to the bottom, and act as I-beams. The completed material's modulus is 97%-98% that of continuous carbon fber, and its tensile strength is 60%-70%, though—as Dodworth points out—"This isn't the wing of a Boeing 787, it's a car, a fve-sided shoebox, where stifness is the most important factor." Even more impressive is the fact that the DCFP panels are about 1/10 the cost of continuous fber items, and have Class A surfaces. Each panel is formed in an inexpensive hot aluminum die where two rectangles of DCFP are clamped in place with a single 20-mm polycarbonate core in-between. Resin is sprayed on each side of the sandwich, and the die is closed to form the panel to its fnal shape. The whole process takes 12 minutes. A fange of compressed material approximately 6.0-mm thick around the edge of the panel acts as both a barrier to water intrusion and a bonding surface for joining the panels together. Unlike a continuous carbon fber tub, the DCFP panels used by Zenos can be replaced after a major accident. Zenos takes delivery of the panels for the front and rear bulkheads, sides, and foor, and bonds them together around the aluminum beam. This single-piece extrusion is 2.1-meters long, was optimized using FEA by Multimatic, and is the main source of the car's torsional rigidity. "The panels butt up against one another in a simple jig," says Ali, "and are adhesively bonded, with mechanical fasteners used in tear-prone areas. We place a thin sheet of fberglass between the bottom of the aluminum beam and top of the foorpan to prevent any galvanic corrosion between the two materials, before bonding the foor to the bottom of the beam." Hidden behind the DCFP side panels are tubular steel impact bars that connect to the similarly constructed rollover hoop. The side impact bars are hidden from sight by the interior closure panels. A U-shaped rear subframe carries the powertrain (a 200-hp, naturally aspirated Ford 2.0-liter four cylinder mated to either a fve- or six-speed manual transmission), and is built up from extrusions. Each corner of the subframe is both bonded and mechanically fastened, and then bonded and mechanically afxed to the transverse section of the main beam. The front dampers are located atop the spine, and are actuated by extra-long wishbones, pushrods and rockers. "It's not because we wanted to emulate a Formula One car or deliberately minimize unsprung weight," says Ali. "We wanted to protect a relatively expensive component that might have to be replaced in an accident. In our design, the suspension arms become sacrifcial members, and this helps reduce the running costs of the car over its lifetime." The frst two prototypes are currently undergoing testing in England. They have been pavé tested at the Millbrook Proving Ground, run at speed for long periods at the Snetterton race track, and are taken home at night and over the weekends by Zenos employees, including Ali and Edwards, for on-the- road evaluation. A test session at Millbrook at the end of August allowed depositors to get their frst run in the car, and provide feedback. Final development began in September, leaving just four months to complete this process before production begins in January 2015. Ali and Edwards plan to build 150 to 200 cars in the frst year from their 7,000 ft 2 facility in Wymondham, just down the road from Lotus headquarters in England. Currently, the company consists of 12 people including Ali and Edwards, a design engineer, a body engineer, u U-shaped rear subframe is bonded and mechanically fastened to transverse beam that slides through the main spine before adhesively and mechanically bonded top plates are added. Each subframe extrusion comes from the same tool, and the corners are capped by bonded, fastened brackets. AD&P; > October 2014 > FEATURE > Creating a Low-Cost Chassis Architecture > Christopher A. Sawyer