As the global auto industry wrote the final chapter on its first century, we saw the average thickness of an automotive instrument panel drop from 3.0 mm-3.5 mm to 2.0 mm-2.3 mm, as found in the 1999 Volkswagen Jetta and Golf. By reducing the wall thickness of the instrument panel, Volkswagen started an industry trend: both OEMs and tiers are investigating technologies to produce parts that combine a lower cost-per-part via material optimization and cycle-time reduction with the superior performance of engineering thermoplastics. The goal is to produce parts that are positioned more competitively at every stage of the development cycle - from design, to manufacturing, to assembly, to “curb appeal” on the showroom floor.
The key to this manufacturing and design “sweet spot” is a technology called thinwall - the molding of plastic parts from engineering thermoplastics with wall thicknesses thinner than conventional parts of similar geometry. The actual cutoff in thickness will vary based on a number of variables, including the size and flow length of the part.
Automotive designers and manufacturers are starting to explore the potential of thinwall technology as a cost-reducing processing method that enables faster cycle times and lighter-weight parts using less material.
The potential benefits of thinwall go far beyond the ability to produce smaller, lighter-weight, thermoplastic parts. While it is tempting to assign a thickness at which there is a transition from standard wall to thinwall, the actual cutoff will vary with the size and flow length of the part. The methodology of thinwall technology can be applied at any thickness.
This paper will focus on key design development tools used to facilitate the development of low-cost thinwall instrument panel systems utilizing high performance engineering resins.