Ford Motor / Dow Automotive Design Team Solves Knee Bolster Problems on the 1997 F-Series Pickup and Expedition 980441

The 1997 F-Series and Expedition Instrument Panel programs were initially launched with steering column and glove compartment knee bolsters constructed of compression molded, glass filled polypropylene. First run capability of the material at production speeds was only 65 percent due primarily to dimensional stability (warp), paint adhesion, and excessive rework issues.

A Ford APO (now Visteon) / Dow Automotive^† team was formed to seek a replacement material / design for the glass filled polypropylene material which would solve the problems. The new material system had to meet or exceed current FMVSS 208 crash performance standards, provide improved quality and reduce variable and scrap costs all with a minimum tooling investment. Using Dow PULSE^™ PC/ABS resin, the team designed / implemented a new knee bolster system in 12 months. The redesigned steering column and glove compartment door assemblies had greater dimensional stability, fewer paint adherence / repairability issues, and little or no post molding rework when compared to the previous system. The team worked in tandem with the manufacturing engineers and assembly line operators during all phases of the developmental process to ensure that a robust, manufacturable system was developed.

All of the above mentioned aspects will be discussed in the paper as well as future plans for additional improvements.