A new force term for the particle based cloth drape simulation has been defined in this study. In the sewing process which is the starting point of a cloth drape simulation, usually large constraint forces are assigned along the sewing edges and this may generate a very stiff linear system which tends to diverge easily. Therefore, especially for a dynamic cloth simulation with a large time step, additional large damping should be introduced to stabilize the sewing process which slows down the process significantly. The new force term defined in this study was proved to be able to stabilize the sewing process without such a large damping by preserving the surface normal directions of mesh elements.