<p>In this paper, the time-varying dynamic parameters of thin-walled components are predicted by using the fixed-component modal synthesis (CMS) method and dead element technique. First, the finite element model (FEM) of the entire thin-walled component is established by using the glue command before subdividing the substructures to avoid the need for node renumbering during the procedure of coupling different substructures. Subsequently, the component is divided into two distinct substructures: the constant workpiece (CW) and the workpiece to be removed (WTBR). Then, first coordinate transformation is implemented to achieve the reduced-order model of the CW. Next, the FEM of the WTBR is coupled with the reduced-order model of CW. Thereafter, the material removal process of milling is simulated by using the dead element technique. The process of material removal is simulated after coupling, which eliminates the need for repetitive coupling of substructures unlike with alternative methods. Afterward, the second coordinate transformation is implemented to facilitate the interconnection between the CW and WBTR. The complete forecasting process is comprehensively elucidated through the integration of Ansys, MATLAB, and CAM environments. Finally, experimental verification is conducted. The natural frequencies obtained by the presented method are compared with those obtained by the full-order model and the hammer impact tests in terms of calculation efficiency and accuracy.</p>