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DaimlerChrysler uses SMC Decklids on Prestige Vehicles

27 August 2004

DaimlerChrysler has underscored the company’s commitment to Sheet Moulding Compound (SMC) as the choice material for decklids.

SMC decklids are now specified for the Mercedes Benz CL and CLK ranges as well as for the luxurious Maybach 57 and 62 models.

The SMC decklid is a sophisticated and complex component developed for series production by Peguform, in close cooperation with the full service vehicle supplier Karmann and the OEM, DaimlerChrysler. The composite parts are produced in Peguform’s plant in Rastatt and then sent as a modular component to Karmann for assembly.

The decklid for the CLK Cabriolet, for example, was designed in three parts: a two-part outer skin and a single piece structural sub-frame. Due to the difference in number plate configuration between the European and American markets, two sets of tooling were needed for the vertical face of the outer skin.

The surface of the outer skin is in-mould-coated during the finishing process, to meet the high demands of a class A surface. Structural properties are largely determined by the inner skin of the decklid, which also has ample space for the attachment of the numerous antennae systems. SMC is fully permeable to radio signals, which enables GPS, GSM and AM antennae and amplifiers to be invisibly mounted within the decklid. This integration of functions means optimised design and considerable savings in assembly time.

The finished component is mounted directly onto a steel frame and painted on-line (by E-Coat), thus avoiding any colour matching problems with the rest of the vehicle. The thermal stability of the Class A-SMC from Menzolit-Fibron, enables the component to withstand the high baking temperatures of 190 ºC without any loss of surface quality or dimensional tolerance.

Peguform also utilises the same process technology to produce deck lids for the DaimlerChrysler CL 500, CL 600, CL 55 AMG and the luxury ‘auto-yachts’ Maybach 57 and 62. With the technically advanced flagship Maybach priced between $300,000 and $400,000, there can be no compromising in the quality of materials used.

Only one thousand or so are hand-built every year, which is a good example of composites fulfilling the highest requirements for design, quality and function.