Speedy studied KTW's design using software from Algor Inc. of Pittsburgh. KTW provided Speedy Engineering with a rough draft of the geometry in universal IGES file format, a common method of exchanging geometry when the CAD and FEA systems are on separate computers. On reviewing the first IGES file, it was clear that a change in export parameters was needed, but once the final CAD geometry file was received, final meshing and FEA computation were finished in two days. The results confirmed that the fixture was stiff enough to fulfill all of Porsche's requirements, and the casting process could begin. To shorten the operation start-up time, Speedy suggested to KTW that it also analyze the dynamic behavior of the fixture component.
Every machined part has to have a high-quality surface.
If a vibrating tool causes resonance, the machined part's surface may be unacceptably rough. If the machined part, the fixture, the machine, or a combination of these items has resonance frequencies resembling those of the tool frequencies, the surface is destroyed and the part becomes unusable. It is important, therefore, to choose machining frequencies that will not cause resonance. The new part is used with varying support and rotational speeds until settings are found that avoid resonant frequencies. A dynamic analysis can be carried out on the model used for the displacement analysis, provided that the FEA model's mesh is fine enough.