Abstract
The relation of thread tension, seam puckering, mechanical properties of fabric, and dynamic thread tension was studied to clarify the mechanism of seam pukering. The thread tension was estimated using the relation between the twist angle of thread and tensile forces in a seam. The estimated thread tension was less than one-third of tension of the dynamic needle thread when take-up lever is at the highest position. As the estimated thread tension increases, seam puckering gets worse. It is shown that the estimated thread tension is higher in the fabric with high bending stiffness, even when the same degree of puckering occurs.
